Article

Cost and Effectiveness of Intrapartum Group B Streptococcus Polymerase Chain Reaction Screening for Term Deliveries

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Abstract

To estimate the cost and consequences of intrapartum polymerase chain reaction (PCR) screening on early-onset group B streptococcal (GBS) disease compared with the antenatal lower vagina culture screening recommended in France. This was a single-institution study comparing the intrapartum PCR screening strategy implemented in 2010 with antenatal culture strategy in place in 2009. Early-onset GBS disease in newborns was monitored exhaustively. We estimated direct costs, including screening test costs and hospital costs, for deliveries of healthy newborns compared with those infected with GBS. Costs in 2009 and 2010 were compared on an intention-to-treat basis. Term deliveries were 2,761 and 2,814 in 2009 and 2010, respectively. Among the screened mothers, the vaginal GBS colonization rate was 11.7% based on antenatal GBS culture screening in 2009 compared with 16.7% in 2010 using the intrapartum PCR testing. The overall probabilities of neonatal GBS disease were 0.9% compared with 0.5%, and the average total cost per delivery was $1,759±1,209 in 2009 compared with $1,754±842 in 2010 (P=.9) in antenatal and intrapartum screening strategies, respectively. The number and severity of cases of early-onset GBS disease and the resulting hospital costs were higher in 2009. Polymerase chain reaction intrapartum screening strategy was cost-neutral when compared with the 2009 antenatal lower vagina culture screening, with a significant decrease in early-onset GBS disease.

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... Crucially, they allow for rapid GBS detection amongst women delivering preterm and those with unknown GBS status whilst avoiding the logistical challenges of antenatal screening. Potential drawbacks include delays in the administration of IAP and a lack of antimicrobial susceptibility profiles, however there is growing evidence that intrapartum PCR testing may represent a realistic approach for GBS screening [11,32]. ...
... These guidelines have since been updated to recommend IAP for all women in confirmed preterm labour and IAP or selective screening for those with GBS detected in a previous pregnancy [9]. Broadening the criteria may increase IAP coverage but this is largely dependent on implementation, which is below 50% even in high-income countries [2,7,32]. Concerns that risk factor based approaches offer only limited protection against EOGBS are underscored by the rising incidence of EOGBS in these countries, as previously discussed. ...
... Newer generations of PCR assays, such as the Cepheid Xpert GBS system, yield results in 30-50 min with fully automated sample processing and offer bedside testing with comparable performance to the reference standard of enriched culture [11,31]. El Helali et al. [32] demonstrated the superiority of this strategy for the prevention of proven and probable EOGBS compared to antenatal culture in the largest study of intrapartum PCR screening to date, undertaken in a single centre with 3000 deliveries per annum. Similar proportions of women in both groups received at least 4 h of IAP and intrapartum PCR testing was cost neutral overall due to a large reduction in healthcare expenses for affected infants. ...
Article
Group B streptococcus (GBS) is the most common cause of early-onset neonatal sepsis in many countries and responsible for significant perinatal morbidity and mortality worldwide. Intrapartum antibiotic prophylaxis has been the mainstay of efforts to prevent early-onset GBS disease in recent decades, however it is unclear if women should be targeted based on the presence of clinical risk factors or by screening for GBS colonisation during pregnancy. Universal bacteriological screening of women in late pregnancy has been widely adopted but questions remain regarding its benefits and potential harms. Newer approaches to screening based on rapid point-of-care testing require further evaluation in randomised controlled trials to inform evidence-based practice. Given current preventive strategies do not protect against late onset disease and other sequelae of infection, maternal vaccination against GBS may present the best opportunity to reduce the global burden of invasive GBS disease in the future.
... The Xpert GBS (Cepheid) has the potential to reduce the number of babies developing EOGBSD as well as antibiotic stewardship as it relates to maternal GBS screening and treatment. This new form of screening has since been introduced at various hospitals in Europe and has been found to be cost-neutral when compared to universal antenatal culture-based screening [15]. Further research is needed into the accuracy and cost-effectiveness of point-of-care PCR screening for GBS in different settings. ...
... If intrapartum screening is to be beneficial, the PCR technology needs to: offer high accuracy for identifying GBS status; be user-friendly for the healthcare practitioner; require low maintenance; be cost-neutral or cost-effective compared to other screening methods; lead to a decrease in EOGBSD cases; and, ensure that fewer women unnecessarily receive prophylactic antibiotics [15]. ...
... GBS screening by Xpert GBS (Cepheid) has been found to be "cost-neutral" when compared to universal antenatal culture-based screening [15]. However this outcome was based on screening by vaginal swab rather than a combined vaginal and perianal swab which would be the method used in our study. ...
... They concluded that the screening by PCR at delivery reduced the number and severity of early-onset GBS disease, and also reduced the hospital costs incurred. 20 The primary objective of the present study was to assess whether the determination of vaginal GBS by using the Cepheid rapid PCR assay at delivery was able to spare useless antimicrobial treatments, in comparison with conventional culture at 34-38 weeks of gestation. In parallel, the practical feasibility of the test being available 24 hours a day, 7 days a week, was analysed, together with its analytical performance with reference to bacterial culture. ...
... However, the change in the GBS screening strategy is beyond hospital policy. Cost-effectiveness studies like that of El Helali et al. 20 and this will help health authorities to decide whether molecular testing of GBS at delivery can be included with new recommendations. ...
Article
To assess whether the determination of the presence of group B streptococci (GBS) in the vagina using a rapid polymerase chain reaction (PCR) assay at delivery was able to spare useless antimicrobial treatments, as compared with conventional culture at 34–38 weeks of gestation. Practical evaluation and prospective cost-effectiveness analysis. A university hospital in France. A cohort of 225 women in labour at the University-Hospital of Saint-Etienne. Each woman had a conventional culture performed at 34–38 weeks of gestation. At the beginning of labour, two vaginal swabs were sampled for rapid PCR testing and culture. The decision to prescribe a prophylactic antimicrobial treatment or not was taken according to the result of the PCR test. A comparative cost-effectiveness analysis of the two diagnostic strategies was carried out. Number of women receiving inadequate prophylactic antimicrobial drugs following each testing strategy, costs of PCR testing and culture, frequency of vaginal GBS, and diagnostic performance of the PCR test at delivery. The percentage of unnecessarily treated women was significantly reduced using the rapid test versus conventional culture (4.5 and 13.6%, respectively; P < 0.001). The rate of vaginal GBS at delivery was 12.5%. The incremental cost-effectiveness ratio (ICER) for each inadequate management avoided was €36 and €173 from the point of view of the healthcare system and hospital, respectively. The PCR assay reduced the number of inadequate antimicrobial treatments aimed to prevent the early onset of GBS disease. However, this strategy generates extra costs that must be put into balance with its clinical benefits.
... El Helali et. al. concludes that PCR is cost-neutral compared to culture-based screening [41]. Similar conclusions were presented by Picchiassi et al., who endorsed limited cost burden of implantation of intrapartum PCR [42]. ...
... In the above study, El Helali et al. calculates costs of a unit of penicillin G, culture test, and PCR test as $1.5, $4.8, and $48.5, respectively. Thereby, the cost of culture is approximately 3.2 times the cost of a unit of penicillin G, cost of PCR test is 32 times the cost of penicillin G, and cost of PCR is 10.1 times the cost of culture [41]. In Egypt, an example of a low-resource country, cost of PCR is roughly 180 times the cost of penicillin G, cost of culture is 14 times the cost of penicillin G and cost of PCR is 12.9 times the cost of culture. ...
Article
Rectovaginal colonization with group B streptococcus (GBS) is commonly encountered in pregnancy. GBS is the most common cause of early onset neonatal sepsis, which is associated with 12% case-fatality rate. Although screening protocols and prophylactic treatment are readily available worldwide, practice in low-resource countries is challenged by lack of awareness and limited implementation of these protocols. In addition, antibiotic susceptibility pattern may vary globally owing to different regulations of antibiotic prescription or prevalence of certain bacterial serotypes. This guideline appraises current evidence on screening and management of GBS colonization in pregnancy particularly in low-resource settings.
... An automated system requiring the minimum of maintenance and set-up is desirable. Indeed a reliable, robust and rapid test should be cost-effective, leading to the prevention of more cases of neonatal GBS EOD while reducing the number of women receiving unnecessary IAP [97,98]. ...
... A key success factor was the empowerment of the midwives in the management of PCR processing when the women need it, without loosing time in bringing the sample to the laboratory or in waiting for the communication of the screening result. In 2012, El Helali et al. reported this experience in 2814 deliveries and showed the superiority of this new strategy for prevention of perinatal GBS early onset disease at a neutral cost when compared to the vaginal antenatal cultures performed at 35-37 weeks gestation in 2761 deliveries [97]. According to this study, the number and severity of GBS EOD cases and the resulting hospital costs were significantly lower. ...
Article
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Abstract Group B streptococcus (GBS) remains worldwide a leading cause of severe neonatal disease. Since the end of the 1990s, various strategies for prevention of the early onset neonatal disease have been implemented and have evolved. When a universal antenatal GBS screening-based strategy is used to identify women who are given an intrapartum antimicrobial prophylaxis, a substantial reduction of incidence up to 80% has been reported in the USA as in other countries including European countries. However recommendations are still a matter of debate due to challenges and controversies on how best to identify candidates for prophylaxis and to drawbacks of intrapartum administration of antibiotics. In Europe, some countries recommend either antenatal GBS screening or risk-based strategies, or any combination, and others do not have national or any other kind of guidelines for prevention of GBS perinatal disease. Furthermore, accurate population-based data of incidence of GBS neonatal disease are not available in some countries and hamper good effectiveness evaluation of prevention strategies. To facilitate a consensus towards European guidelines for the management of pregnant women in labor and during pregnancy for the prevention of GBS perinatal disease, a conference was organized in 2013 with a group of experts in neonatology, gynecology-obstetrics and clinical microbiology coming from European representative countries. The group reviewed available data, identified areas where results were suboptimal, where revised procedures and new technologies could improve current practices for prevention of perinatal GBS disease. The key decision issued after the conference is to recommend intrapartum antimicrobial prophylaxis based on a universal intrapartum GBS screening strategy using a rapid real time testing.
... They would allow a better management of colonized mothers and their infants as the targeted IAP would then be limited to GBS carriers, reducing unnecessary treatment. Currently, there are GBS-specific real-time PCR assays that provide this potential alternative for rapid GBS detection [105,106]. However use of these more expensive rapid tests is not currently widespread. ...
... However, use of this relatively new and more expensive technology is not currently widespread among European hospitals and must still be assessed for its use in the screening-based strategy. Haberland & Benitz's cost analysis suggested that rapid simple NAAT benefits exceed their costs in Europe, one of the first experiences in a clinical setting has showed its superiority for prevention of perinatal GBS early onset disease at a neutral cost when compared to the vaginal antenatal cultures performed at 35-37 weeks gestation and has been implemented as unique screening in term deliveries [106]. Further studies using real-time NAAT performed in intrapartum setting are needed to identify targeted population and settings where the test will be most useful. ...
Article
Development of a group B streptococcal vaccine (GBS) vaccine is the most promising approach for the prevention of GBS infections in babies, given the potential adverse effects of intrapartum antibiotic prophylaxis as well as the need for effective prevention of both adult and late perinatal disease. There are numerous prevention strategies at this time but none are 100% effective in the eradication of neonatal early onset GBS disease and there are no preventative strategies for late onset disease. The need for a GBS vaccine is therefore, of utmost importance. Efforts applying genomics to GBS vaccine development have led to the identification of novel vaccine candidates. The publication of GBS whole genomes coupled with new technologies including multigenome screening and bioinformatics has also allowed researchers to overcome the serotype limitation of earlier vaccine preparations in the search of a universal effective vaccine against GBS. This review brings together the key arguments concerning the potential need of a GBS vaccine in developed countries and describes the current status with GBS epidemiology and microbiology in these countries.
... Different authors have studied the cost of GBS culture screening versus PCR testing. Taking into account that the lower sensitivity of GBS culture methods results in unnecessary intrapartum antibiotic prophylaxis, an increase in hospital stay expenses, and early-onset GBS disease not detected by culture, they concluded that the final cost for both techniques was similar [49]. Considering the results of the present study, in which 11 samples (3.44% of total) that were positive for GBS were not detected by the culture method, introduction of amplification techniques in the diagnosis routine appears to be supported. ...
Article
Full-text available
Background Streptococcus Group B (GBS) colonization in pregnant women is the most important risk factor for newborn disease due to vertical transmission during delivery. GBS colonization during pregnancy has been implicated as a leading cause of perinatal infections. Traditionally, pregnant women are screened for GBS between 35 and 37 weeks of gestation. However, antenatal culture-based screening yields no information on GBS colonization status and offers low predictive value for GBS colonization at delivery. Numerous assays have been evaluated for GBS screening in an attempt to validate a fast and efficient method. The aim of this study was to compare bacteria isolation by culture and two qPCR techniques, targeting sip and cfb genes, respectively, for detecting colonizing GBS. Methods Cultures – the gold-standard technique, a previous qPCR technique targeting the sip gene, and a new proposed qPCR assay targeting the cfb gene were evaluated as diagnostic tools on 320 samples. ResultsConsidering cultures as the gold standard, the evaluated qPCR method detected 75 out of 78 samples, representing a sensitivity of 93.58% (95% confidence interval (CI), 90.89–96.27) and specificity of 94.62% (95% CI, 91.78–97.46). However, an additional analysis was performed for true positives that included not only samples showing positives by culture but samples showing positive for both qPCR assays. The sensitivity and specificity were recalculated including these discrepant samples and a total of 89 samples were considered as positive, giving a prevalence of 27.81%. With this new analysis, the qPCR targeting the cfb gene showed a sensitivity of 95.5% (95% CI, 88.65–98.59) and specificity of 99.13% (95% CI, 96.69–99.97). Conclusions The new qPCR method is a sensitive and specific assay for detecting GBS colonization and represents a valuable tool for identifying candidates for intrapartum antibiotic prophylaxis. Cultures should be retained as the reference and the routine technique because of its specificity and cost analysis ratio, but it would be convenient to introduce PCR techniques to check negative culture samples or when an urgent detection is required to reduce risk of infection among infants.
... [3][4][5] In order to reduce the incidence of early-onset GBS infection, all of the pregnant women should be screened for GBS and intrapartum antibiotic prophylaxis should be administered to GBS-colonized mothers. 6 Therefore, since 2002, the Center of Disease Control in the United States has recommended a universal vagina-rectum GBS screening at 35-37 weeks of gestation. 7 Accordingly, since 2001, in France, a universal lower vagina culture screening has been recommended at 35-38 weeks. ...
Article
Full-text available
Objective: The present study aims to evaluate the efficiency of a rapid real-time polymerase chain reaction (PCR) assay in order to determine maternal group B streptococcus (GBS) colonization in the third trimester of pregnancy. Material and Methods: This prospective study reviewed 70 healthy women with term pregnancies who were consecutively admitted to the study center for routine prenatal care from June 2012 to December 2012. Results: The prenatal GBS colonization rate was 15.7% by the PCR technique. Perinatal complications including abortus imminens, fetal growth restriction, premature rupture of membranes, preterm delivery, meconium stained amniotic fluid and chorioamnionitis were significantly more frequent in women with GBS positivity (respectively p=0.011, p=0.023, p=0.001, p=0.001, p=0.023 and p=0.001). Puerperal fever was significantly more frequent in women who were GBS positive (p=0.001). The need for neonatal intensive care unit and neonatal pneumonia were significantly more frequent for the neonates that were born to women with GBS positivity (p=0.001 for both). Conclusion: The real-time PCR assay can be defined as an accurate test to identify the GBS carriers at the third trimester of pregnancy. This easily applicable tool could enhance the exact identification of candidates for chemoprophylaxis, including women carrying a risk for premature rupture of membranes or preterm labor.
... Further studies are needed to delineate if the higher representation of falsely-screened young and black women in our study are due to different rates of acquisition versus inadequate sampling and disparities in obstetrical care. Intrapartum polymerase chain reaction for GBS has been shown to be highly sensitive and specific, (23)(24)(25)(26) and could increase sensitivity for detecting GBS that is acquired after typical prenatal screening. ...
Article
Objective: The aim of this study was to identify risk factors for early-onset group B Streptococcus (EOGBS) disease in neonates of mothers with negative antenatal screening. Study design: We performed a retrospective cohort study of neonates born to mothers with negative antenatal GBS screening between 2002 and 2012. Our primary outcome was EOGBS infection. We used multivariable logistic regression to assess factors associated with EOGBS. Results: EOGBS was confirmed in 492 of the 179 818 neonates that met the study inclusion criteria. Risk factors for EOGBS included black race (reference: white, odds ratio (OR) =1.81 (95% confidence interval: 1.43, 2.31)), maternal age <18 years (reference: >35 years, OR=2.63 (1.54, 4.51)) and maternal age 18 to 35 years (reference: >35 years, OR=1.94 (1.30, 2.88)). Conclusion: Maternal age <18 years and black race were the strongest predictors of EOGBS. Further research investigating contributors to the discordance between screening results and neonatal outcomes in these populations is needed.Journal of Perinatology advance online publication, 17 November 2016; doi:10.1038/jp.2016.201.
... The current studies have not identified significant penicillin resistance, but depending on the region, 10 to 38% and 5.0 to 51% of isolated GBS have resistance to erythromycin and clindamycin, respectively (30,31). A second study found that PCR screening during pregnancy would be cost neutral and may result in an overall reduction in early-onset GBS disease (32). A small reduction in the incidence of early-onset GBS disease based on the use of a molecular test might also justify the additional cost because, on average, the cost of an early-onset GBS infection is Ͼ€19,000, and infants who survive incur health care and social care costs twice as high as those for unaffected infants (33). ...
Article
Neonatal infection with Streptococcus agalactiae, or group B Streptococcus (GBS), is a leading cause of sepsis and meningitis in newborns. Recent guidelines have recommended universal screening of all pregnant women to identify those colonized with GBS, and administration of peripartum prophylaxis to those identified as carriers to prevent neonatal infection. Enriched culture methods are the current standard for prenatal GBS screening; however, implementation of more sensitive molecular diagnostics may be able to further reduce the risk of early-onset GBS infection. We report a clinical evaluation of the Xpert GBS LB Assay, a molecular diagnostic test for the identification of GBS from broth-enriched vaginal/rectal specimens obtained during routine prenatal screening. A total of 826 specimens were collected from women undergoing prenatal screening (35-37 weeks gestation) and tested at one of three clinical centers. Each swab specimen was tested directly prior to enrichment using the Xpert GBS assay. Following 18-24 h broth enrichment, each specimen was tested using the Xpert LB Assay as well as the FDA-cleared SMART GBS Assay as a molecular comparator. Results obtained using all three molecular tests were compared to broth enriched culture as "gold standard". Sensitivity and specificity of the Xpert GBS LB Assay was 99.0% and 92.4%, respectively, compared to gold standard culture. The SMART GBS molecular test demonstrated sensitivity and specificity of 96.8% and 95.5%, respectively. Sensitivity of both broth-enriched molecular methods was superior to direct testing of specimens using the Xpert GBS Assay, which demonstrated sensitivity and specificity of 85.7% and 96.2%, respectively. Copyright © 2014, American Society for Microbiology. All Rights Reserved.
... In my opinion, intrapartum rapid PCR should be the gold standard when deciding to systematically screen GBS in pregnant women. A French group studied the cost of providing PCR in the labor suite for GBS carriage [106]. They showed that the PCR strategy is cost-neutral compared to the antenatal culture strategy if the cost of treating GBS-infected newborns is taken in account, and with the additional benefit of decreasing the incidence of GBS sepsis. ...
Article
Full-text available
Although pregnancy is considered as a physiological state, most pregnant women in developed countries receive multiple medications to prevent maternal or neonatal complications, with antibiotics among the most frequently prescribed. During pregnancy, antibiotics are often prescribed in the context of preterm labor, intrapartum fever, prevention of neonatal Group B Streptococcus fever, and cesarean section. Outside this period, they are commonly prescribed in the community setting for respiratory, urinary, and ear, nose and throat infection symptoms. Whereas some of the current indications have insightful reasons to justify their use, potential risks related to overuse and misuse may surpass the benefits. Of note, the recent 2014 World Health Assembly expressed serious concern regarding antibiotic resistance due to antibiotic overuse and misuse and urged immediate action to combat antibiotic resistance on a global scale. Most studies in the obstetrics field have focused on the benefits of antibiotics for short-term maternal and neonatal complications, but with very little (if any) interest in long-term consequences.
... Rapid, reliable and accurate (both sensitivity and specificity> 90%), Nucleic Acid Amplification Tests (NAATs) have been recently introduced to detect GBS carriage status, especially in the delivery room [26,29]. Although more expensive than standard antenatal cultures, NAATs could avoid unnecessary treatment of women with positive screening that become negative at delivery screening, thus resulting in being also cost-saving methods [30,31]. ...
Article
Full-text available
Sudden infants' death is one of the most important matters in forensic medicine. The ability to pose a differential diagnosis between internal/infection and external/violent death is of paramount importance. Here, we report a case of a sudden death of an infant due to early-onset Group B Streptococcal (GBS) sepsis diagnosed by post-mortem microbiology analysis, since the mother was negative at vaginorectal GBS screening by culture. This case report highlights the importance of rapid and accurate nucleic acid amplification tests to detect GBS carriage status, especially in the delivery room.
... Many studies showed that IAP could have long-term implications as the alteration of gut microbiota, improper maturation of immune system with possible health problems in adult life [21,22]. So far, only the study of El Helali et al. [23] evaluated the cost-effectiveness of intrapartum test at level of pregnancy and neonatal management, showing that this test was cost-neutral when compared to antepartum culture. A weakness of intrapartum test was the percentage of missing results, as previously reported by other authors [14,17,24]. ...
Article
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Purpose: To evaluate the potential improvement of introducing an intrapartum test for the detection of Group B Streptococcus (GBS) during labor and to estimate its cost-effectiveness versus antepartum GBS screening culture. Materials and methods: Three hundred thirteen women at beginning of labor, with unknown GBS status or with antepartum GBS screening culture were enrolled. A vaginal-rectal specimen was collected from each woman for GBS detection by real time PCR. Results of intrapartum test and antepartum GBS screening culture were compared. Results: Antepartum culture results did not always reflect the intrapartum maternal GBS colonization status since in 15.1% of the cases it was not concordant with intrapartum test. However, selecting only women, who underwent antepartum culture and intrapartum test at the same time, the percentage of concordance was 96.6%. Based on intrapartum test results, 74.9% of the total number of intrapartum antibiotic prophylaxis (IAP) was administered uselessly, while 1.9% of women did not receive IAP although they were positive to intrapartum test. Intrapartum test resulted less cost-effective than antepartum culture but it became more cost-effective at a cost threshold of about 16.00 €. Conclusions: The clinical introduction of intrapartum test could be a valuable mean for identification of GBS colonization during labor, allowing an appropriate management of mothers and neonates with consequent benefit for their health and with limited costs for Healthcare System.
... Third, a cost-benefit analysis has not been performed in our study. However, such analyses have already been published by Haberland et al. [20] and El Helali et al. [21], demonstrating the cost-effectiveness of intrapartum PCR-based strategies compared to antepartum culture screening, since they generate more benefits per birth, result in fewer courses of IAP, and, eventually, in fewer cases of EOD. Although the cost of such tests restricts their implementation and routine use on many maternity wards, their effectiveness and associated benefits will very likely contribute to their popularization and favor their reimbursement by health care insurances in the near future. ...
Article
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Group B Streptococcus (GBS) is the leading cause of neonatal infections in industrialized countries. Intrapartum antibiotic prophylaxis (IAP) given to colonized parturients is a key step for the prevention of neonatal early-onset infection. We compared the performances of Xpert® GBS polymerase chain reaction (PCR) (Cepheid, Sunnyvale, CA, USA) as a point-of-care system in labor wards to standard culture for intrapartum GBS detection. Pregnant women with a GBS-positive antenatal screening were prospectively included. A vaginal double swab was collected at the time of delivery for point-of-care Xpert® GBS PCR and GBS culture. A total of 565 pregnant women were included. Valid Xpert® GBS results were obtained for 488 (86.4%) women on the first attempt. Repeat testing improved the PCR success to 516 (91.3%) women. Among the 305 women positive for GBS by culture at delivery, only 238 (78.0%) were positive by Xpert® GBS PCR, cycle thresholds being correlated to culture quantification. Among 260 women negative for GBS culture, 56 (21.5%) were positive by Xpert® GBS PCR, including 50 where IAP was initiated before vaginal sampling. Overall, among the 565 women with GBS antenatal positive culture, only 335 (59.3%) were still positive at delivery whatever the technique used, resulting in unnecessary IAP for 40% of them. This large cohort study comparing intrapartum to antepartum GBS detection provides evidence that (i) Xpert® GBS PCR might be a valuable solution for intrapartum GBS detection compared to culture-based strategies and (ii) laboratory training of non-specialized staff is mandatory to reach the performances required for point-of-care tests.
... The reported rates by these studies, ranged between 21.5 and 61.4%, [16,31,32] were consistent with our study observed rate of 30.4% (7/23). To improve the accuracy of screening by identifying the GBS status, a rapid polymerase chain reaction (PCR) test could be used at the time of labor to increase the sensitivity and specificity of the tests [33][34][35]. ...
Article
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Background The epidemiology of maternal and infant Group B streptococcus (GBS) colonization is poorly understood in China. The aim of this study is to explore the prevalence and risk factors associated with maternal and infant GBS colonization in Western China. Methods From January 2017 to June 2017, a prospective study was conducted to estimate the maternal and infant GBS colonization rate by maternal rectovaginal and infant nasopharynx, ear canal and umbilical swab culture. Patient demographics, clinical characteristics and outcomes were collected. Chi-square and logistic regression analyses were used to examine the risk factors associated with GBS colonization of mothers and infants. Results The GBS colonization rate in mothers and infants was 6.1 and 0.7%, respectively. The vertical transmission rate was 7.6%. The early onset GBS infection rate was 0.58 per 1000 live births and mortality was 0.29 per 1000 live births. Age younger than 40 years (p = 0.040) and minority ethnic status (p = 0.049) were associated with higher GBS colonization rate in pregnant women. Positive GBS status in the mother prior to delivery (p < 0.001) as well as longer duration of membrane rupture (≥12 h) (p < 0.001) and longer labor (≥4 h) (p < 0.001) were all significant risk factors for GBS colonization in infants. Compared to infants without GBS colonization, infants colonized with GBS were more likely to have had a temperature of ≥38 °C (p < 0.001), developed early onset infection (EOD) (p < 0.001), and been prescribed antibiotics (p < 0.001). Furthermore, infants with GBS were more likely to have been admitted to neonatal intensive unit (NICU) (p < 0.001) with a longer hospital length of stay (LOS) (p < 0.001). Conclusions Maternal GBS colonization, longer duration of membrane rupture and labor were all major risk factors associated with GBS colonization in Chinese infants. Infant GBS colonization was associated with increased risk of EOD and NICU admission as well as longer LOS.
... Enriched and direct cultures were shown to have similar performances (9), although failure to perform direct culture can decrease sensitivity due to overgrowth of competing organisms in enrichment broth (13). Finally, nucleic acid amplification tests (NAATs), notably those including the extraction step, reduce the delay in results and could be used at the admission of pregnant women in active labor in order to administer adequate antibiotic prophylaxis (14,15). NAATs offer similar performances compared to direct selective culture (16), but controversial results were reported after comparison with enriched culture (7,9,17,18). ...
Article
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Three commercial chromogenic agar media were evaluated for Streptococcus agalactiae screening in 200 vaginal swabs from pregnant women. The sensitivity and specificity were 94.3% and 100% for Granada medium (bioMérieux), 100% and 90.3% for Brilliance GBS medium (Thermo Fisher Scientific), and 100% and 98.8% for ChromID STRB medium (bioMérieux), respectively.
... Recently a single-institution study showed that PCR-based screening was cost neutral compared to the GBS culture screening. A significant decrease in GBS-EOD was also detected [25]. ...
Article
Group B streptococci (GBS) may lead to early onset neonatal sepsis with severe morbidity and mortality of newborns. Intrapartum detection of GBS is needed. The objective was to compare a PCR-based test performed in the laboratory versus labor ward. 300 patients were included prospectively. In phase I, swabs were analyzed by selective culture and rapid PCR in the laboratory. In phase II, swabs were analyzed accordingly, but the PCR test was conducted in labor ward. Test performances were analyzed and compared. In phase I the rapid PCR test had a sensitivity of 85.71% and a specificity of 95.9%. The GBS colonization rate was 18.67%. Overall 8.5% of the PCR results were invalid. In phase II the PCR test showed a sensitivity of 85.71% and a specificity of 95.65%. The GBS colonization rate was 23.3%. Overall 23.5% of swabs tested with PCR were invalid. Initiation of specific, short 2-hour training for operating personnel in the labor ward reduced the invalid test rate to 13.4%. The rapid PCR-based test yields adequate results to identify GBS colonization when performed in labor ward. In order to reduce the number of invalid tests a short training period is needed.
... 10 Since January 2010, the 40 midwives of our institution perform exclusively intrapartum GBS molecular screening around-the-clock on the GeneXpert system located in the delivery suite for all term deliveries instead of antenatal culture screening. 11 A key success factor of the adoption of intrapartum screening was the empowerment of the midwives in the management of PCR processing without wasting time and the assurance that the result would be available to take appropriate action. ...
Article
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Objective: To assess outcomes and costs associated with around-the-clock point-of-care intrapartum group B streptococcus (GBS) polymerase chain reaction (PCR) screening. Methods: Intrapartum PCR screening was implemented in 2010. Intrapartum PCR was compared with antenatal culture screening in an uncontrolled, single institution, preintervention and postintervention study. The study periods included 4 years before and 6 years after the intervention, commencing in 2006 and concluding in 2015. The primary outcome measure was rate of early-onset neonatal GBS disease. Secondary outcomes included length of stay, days of antibiotics, and costs. Results: During the 4 years of antenatal culture screening, 11,226 deliveries were recorded compared with 18,835 in the 6 years of intrapartum GBS PCR screening, corresponding to 11,818 and 18,980 live births, respectively. During the antenatal culture period, 3.8% of term deliveries did not undergo GBS testing compared with 0.1% during the intrapartum PCR period (P<.001). Between the two periods, the rate of proven early-onset GBS disease cases decreased from 1.01/1,000 to 0.21/1,000 (P=.026) and probable early-onset GBS disease cases from 2.8/1,000 to 0.73/1,000 (P<.001); the risk ratio for both was 0.25, 95% CI (0.14-0.43). Total days of hospital and antibiotic therapy for early-onset GBS disease declined by 64% and 60%, respectively, with no significant difference for average length of stay or antibiotic duration preintervention and postintervention. The yearly cost of delivery and treatment of newborns with GBS infection was reduced from $41,875±6,823 to $11,945±10,303 (P<.001). The estimated extra cost to avoid one early-onset GBS disease was $5,819. Conclusion: Point-of-care intrapartum GBS PCR screening was associated with a significant decrease in the rate of early-onset GBS disease and antibiotic use in newborns. The additional PCR costs were offset in part by the reduction in early-onset GBS disease treatment costs.
... Several U.S. Food and Drug Administration (FDA)-cleared NAATs can be used to detect GBS in enrichment broth, and at least one FDA-cleared test can be used directly on vaginal/rectal swabs without broth enrichment for intrapartum testing (7)(8)(9)(10)(11)(12)(13). Intrapartum testing results are critical for women who present in labor prior to 35 weeks, who failed to have the surveillance cultures performed before time of delivery, or who do not have other indications for antimicrobial therapy to prevent EO-GBS disease (10). Intrapartum testing to detect GBS colonization is also used in many regions of the world in lieu of antepartum surveillance testing (14)(15)(16). In many laboratories, NAATs have replaced subcultures of enrichment broths to agar media because of NAATs' improved workflow efficiency and its enhanced sensitivity, especially for the detection of nonhemolytic GBS strains or strains that do not produce CAMP factor, which may go undetected by culture (8,17). ...
Article
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Surveillance of circulating microbial populations is critical for monitoring the performance of a molecular diagnostic test. In this study, we characterized 31 isolates of Streptococcus agalactiae (Group B Streptococcus, GBS) from several geographic locations in the United States and Ireland that contain deletions in or adjacent to the region of the chromosome that encodes the hemolysin gene cfb , the region targeted by the Xpert® GBS and GBS LB assays. PCR-negative, culture-positive isolates were recognized during verification studies of the Xpert GBS assay in 12 laboratories between 2012 and 2018. Whole genome sequencing of 15 GBS isolates from 11 laboratories revealed four unique deletions of chromosomal DNA ranging from 181 base pairs to 49 kilobases. Prospective surveillance studies demonstrated that the prevalence of GBS isolates containing deletions in the convenience sample was <1% in three geographic locations but 7% in a fourth location. Among the 15 isolates with chromosomal deletions, multiple pulsed-field gel electrophoresis (PFGE) types were identified, one of which appears to be broadly dispersed across the United States.
... [1,2]. I would like to comment on the high rate of indeterminate results showed in the study (which we also saw on initial use of the assay), and share my experience with Cepheid Xpert GBS assay for intrapartum testing and relate recommendations implemented in the delivery ward, in order to decrease errors and invalid results.During my experience with Xpert GBS assay, where the test was performed by midwives in the delivery ward of Saint Joseph Hospital, started in 2010, I verified that with the first generation assay (cartridges that required external reagents to be added to the cartridge by the user), the indeterminate results (4.3% of invalid PCRs and 6.5% of errors) were mostly related to the process of adding reagents to the cartridge and to the pre-test management of the samples (swabs with excess mucus, blood, lubricants, etc.). ...
... The current relatively high cost of these techniques may be offset by prevention of both superfluous therapy and missed treatment opportunities. In an ideal situation, it has been suggested that this may make such an approach cost-neutral (8). NAAT for GBS is a very promising approach that may, in time, obviate the need for either of the intrinsically flawed screening policies. ...
Article
In this issue of the journal, Williams et al provide both good and potentially not so good news on the contribution that infections make to neonatal and infant mortality (1). The good news is that the absolute numbers of neonates and infants dying of infectious causes in the north of England fell significantly during the 21 years between 1988 and 2008. In particular, marked reductions were seen in Group B Streptococcus (GBS) during the neonatal period and in Meningococcus during the post-neonatal period. The not so good news was that the proportion of deaths related to infectious causes rose markedly from 12% to 15% during the 21-year study period. This was accompanied by a parallel increase in preterm infants, who accounted for 14% of total deaths in the first 7-year era beginning in 1998 and 38% in the third era ending in 2008. The specific organisms that rose most markedly were E. Coli and Candida sp, which were almost certainly secondary to the increased survival of extremely preterm infants. This article is protected by copyright. All rights reserved.
... Pomimo uzależnienia od wymagań technicznych (ekspertyza laboratoryjna, sprzęt) i znacznie wyższych kosztów diagnostycznych diagnostyka kolonizacji GBS ciężarnych z wykorzystaniem PCR w obserwacji długoterminowej ma neutralny wpływ na budżet państwa. Ograniczenie bowiem zbędnej profilaktyki okołoporodowej u kobiet z fałszywie dodatnimi wynikami screeningu znacznie obniża koszty [29]. ...
Article
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Group B streptococci (GBS), most often Streptococcus agalactiae, are Gram-positive bacteria that colonize the gastrointestinal and genital tract. Colonization of the vagina and rectum in pregnant women poses a risk of transmission of GBS to neonate during vaginal delivery. The above may manifest in newborns as the early onset disease (EOD) – up to the 7th day of life, as well as the late onset disease (LOD) – from the 7th to the 89th day of life. The most common infections are pneumonia, sepsis and meningitis. In the 20th century, GBS was the main cause of neonatal perinatal mortality. Along with the initiation and prevalence of screening (vaginal and rectal swab in women between 35 and 37 weeks of gestation) and intrapartum antibiotic prophylaxis (IAP), a decrease in neonatal morbidity and mortality was observed. According to 2002 CDC guidelines penicillin is recommended as the first line treatment in IAP (ampicillin and amoxicillin are acceptable as alternative treatment). Antibiotherapy is considered effective if administered at least 4 hours prior the delivery. Even 2 hours of antibiotic prophylaxis reduces the incidence of neonatal infections. This procedure, despite its undoubted effectiveness, has various limitations. First of them is the inability to predict changes in GBS colonization status during pregnancy, which leads to the overuse of antibiotics. On the other hand, the imperfection of currently used screening methods can sometimes give false negative results. In addition, the increasing antibiotic resistance of bacteria means that we should carefully reflect on the validity of the use of prophylaxis in the current form.
... When performed in a labor ward setting, fluctuating invalid rates have been reported for GeneXpert; Mueller et al. reported 55.3 % initially invalid GeneXpert results, reduced to 13.4% after 2-h training of midwives [11]. Håkansson et al. reported 15% invalid results as the midwives' experience improved [16], and Helali et al. had 9% invalid results [17]. Not all hospitals have laboratory facilities right next to the labor ward or accessible trained lab personnel on a 24-h basis, and we decided to perform our study in a clinical setting representative for many hospitals/labor wards. ...
Article
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This study was designed to compare the performance of GeneXpert® and GenomEra® group B streptococcus (GBS) PCR assays, held up against standard culture of GBS performed with and without broth pre-enrichment. In Denmark, the strategy for preventing early onset GBS infection (EOGBS) is risk factor based. Three hundred and sixty six women fulfilling one or more of the criteria for presence of risk factors for EOGBS were prospectively included. Rectovaginal swab samples were taken intrapartum and tested bed-site by the GenomEra® and the GeneXpert® GBS PCR assays and cultured at the microbiology laboratory using Granada agar plates with and without prior growth of sampling material in selective enrichment broth. Among 366 participants tested intrapartum, 99 were GBS-positive by culture, 95 by GenomEra, and 95 by GeneXpert. Compared with culture, the GenomEra and the GeneXpert performed with a sensitivity of 91.8% and 91.7% and a specificity of 98.1% and 97.3%, respectively. A combined reference standard was established by defining true positives as either culture-positive samples or culture-negative samples where both the GeneXpert and the GenomEra GBS PCR assays were positive. Using this, the sensitivity increased to 92.2% and the specificity to 99.6% for GenomEra and to 92.0% and 96.8% for GeneXpert. The use of selective broth enrichment found only three additional GBS culture-positive samples. The performance of the two PCR methods examined was very similar and close to the findings by culture, and both PCR assays are thus applicable as rapid intrapartum bed-site tests.
... After the completion of the present study the handling of the assay has been further simplified in that only the culture swab needs to be inserted into the cartridge that now houses all other reagents. El Helali et al. [23] used this latest version of the test in the labor ward with 9% of the results being indeterminate, rendering the assay cost-effective in comparison with late pregnancy screening with conventional culture. ...
Article
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Abstract Objective Intrapartum antibiotic prophylaxis (IAP) reduces the incidence of neonatal early onset group B streptococcal infections. The present study investigated if an automated PCR-assay, used bedside by the labor ward personnel was manageable and could decrease the use of IAP in a setting with a risk-based IAP strategy. Methods The study comprises two phases. Phase 1 was a multicenter, randomized, controlled trial. Women with selected risk-factors were allocated either to PCR-IAP (prophylaxis given if positive or indeterminate) or IAP. A vaginal/rectal swab and superficial swabs from the neonate for conventional culture were also obtained. Phase 2 was non-randomized, assessing an improved version of the assay. Results Phase 1 included 112 women in the PCR-IAP group and 117 in the IAP group. Excluding indeterminate results, the assay showed a sensitivity of 89% and a specificity of 90%. In 44 % of the PCR assays the result was indeterminate. The use of IAP was lower in the PCR group (53 vs. 92%). Phase 2 included 94 women. The proportion of indeterminate results was reduced (15%). The GBS colonization rate was 31%. Conclusion The PCR assay, in the hands of labor ward personnel, can be useful for selection of women to which IAP should be offered.
Article
Objective: To review the evidence in the literature and to provide recommendations on the management of pregnant women in labour for the prevention of early-onset neonatal group B streptococcal disease. The key revisions in this updated guideline include changed recommendations for regimens for antibiotic prophylaxis, susceptibility testing, and management of women with pre-labour rupture of membranes. Outcomes: Maternal outcomes evaluated included exposure to antibiotics in pregnancy and labour and complications related to antibiotic use. Neonatal outcomes of rates of early-onset group B streptococcal infections are evaluated. Evidence: Published literature was retrieved through searches of MEDLINE, CINAHL, and The Cochrane Library from January 1980 to July 2012 using appropriate controlled vocabulary and key words (group B streptococcus, antibiotic therapy, infection, prevention). Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. There were no date or language restrictions. Searches were updated on a regular basis and incorporated in the guideline to May 2013. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies. Values: The quality of evidence in this document was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care (Table 1). Benefits, harms, and costs: The recommendations in this guideline are designed to help clinicians identify and manage pregnancies at risk for neonatal group B streptococcal disease to optimize maternal and perinatal outcomes. No cost-benefit analysis is provided. Summary statement: There is good evidence based on randomized control trial data that in women with pre-labour rupture of membranes at term who are colonized with group B streptococcus, rates of neonatal infection are reduced with induction of labour. (I) There is no evidence to support safe neonatal outcomes with expectant management in this clinical situation. Recommendations: 1. Offer all women screening for colonization with group B streptococcus at 35 to 37 weeks' gestation with culture taken from one swab first to the vagina and then to the rectum (through the anal sphincter). (II-1A) This includes women with planned Caesarean delivery because of their risk of labour or ruptured membranes earlier than the scheduled Caesarean delivery. (II-2B) 2. Because of the association of heavy colonization with early onset neonatal disease, provide intravenous antibiotic prophylaxis for group B streptococcus at the onset of labour or rupture of the membranes to: • any woman positive for group B streptococcus by vaginal/rectal swab culture screening done at 35 to 37 weeks' gestation (II-2B); • any woman with an infant previously infected with group B streptococcus (II-3B); • any woman with documented group B streptococcus bacteriuria (regardless of level of colony-forming units) in the current pregnancy. (II-2A) 3. Manage all women who are < 37 weeks' gestation and in labour or with rupture of membranes with intravenous group B streptococcus antibiotic prophylaxis for a minimum of 48 hours, unless there has been a negative vaginal/rectal swab culture or rapid nucleic acid-based test within the previous 5 weeks. (II-3A) 4. Treat all women with intrapartum fever and signs of chorioamnionitis with broad spectrum intravenous antibiotics targeting chorioamnionitis and including coverage for group B streptococcus, regardless of group B streptococcus status and gestational age. (II-2A) 5. Request antibiotic susceptibility testing on group B streptococcus-positive urine and vaginal/rectal swab cultures in women who are thought to have a significant risk of anaphylaxis from penicillin. (II-1A) 6. If a woman with pre-labour rupture of membranes at ≥ 37 weeks' gestation is positive for group B streptococcus by vaginal/rectal swab culture screening, has had group B streptococcus bacteriuria in the current pregnancy, or has had an infant previously affected by group B streptococcus disease, administer intravenous group B streptococcus antibiotic prophylaxis. Immediate obstetrical delivery (such as induction of labour) is indicated, as described in the Induction of Labour guideline published by the Society of Obstetricians and Gynaecologist in September 2013. (II-2B) 7. At ≥ 37 weeks' gestation, if group B streptococcus colonization status is unknown and the 35- to 37-week culture was not performed or the result is unavailable and the membranes have been ruptured for greater than 18 hours, administer intravenous group B streptococcus antibiotic prophylaxis. (II-2B) 8. If a woman with pre-labour rupture of membranes at < 37 weeks' gestation has an unknown or positive group B streptococcus culture status, administer intravenous group B streptococcus prophylaxis for 48 hours, as well as other antibiotics if indicated, while awaiting spontaneous or obstetrically indicated labour. (II-3B).
Article
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Group B Streptococcus (GBS) infections remain an important cause of perinatal complications, despite advanced preventive measures. The most common clinical symptoms of early-onset disease, diagnosed in neonates up to 7 days of life, are sepsis and pneumonia. Late-onset disease is diagnosed in children between 7 and 89 days of life and presents also in forms of other infections. As a result of collaborative efforts of clinicians, researchers and many organizations, various recommendations for intrapartum prevention of perinatal GBS disease have been issued so far. Revised 2002 CDC guidelines for the prevention of early-onset GBS disease recommended universal culture-based screening of all pregnant women at 35-37 weeks of gestation to optimize the identification of those who should receive intrapartum antibiotic prophylaxis (IAP). They were customized by the Polish Gynecological Society and applied in Poland as well. As a result of preventive efforts worldwide, global incidence of GBS infections has declined dramatically over the past 15 years. About 10-30% of pregnant women are colonized with Group B Streptococcus. According to the literature, GBS culture at 35 to 37 weeks of gestation has about 95% negative predictive value for the absence of colonization at the time of labor. However, studies reporting early-onset GBS disease in newborns found that about 60 to 80% of all cases occurred in neonates with negative maternal screening during pregnancy. If the only available screening test is vagino-rectal swab during pregnancy about 7.5% of women with GBS colonization during labor are not administered IAP. It seems optimal to perform routine screening not during pregnancy but directly before the delivery--preferably at the time of regular uterine contractions or the rupture of membranes. As the screening test should be widely accessible and rapid, the usual microbiological culture is not a suitable option. Recently new biochemical and genetic methods have become available. Polymerase chain reaction (PCR) and optical immunoassay are candidates for rapid patient intrapartum GBS testing to determine whether women in labor are colonized with GBS. PCR tests have the sensitivity of over 90% with the specificity of 99%, which is about 13% higher than microbiological culture. According to the literature, IAP does not reduce the overall neonatal mortality mortality due to GBS infection, or due to other bacterial infections. The incidence of early-onset GBS infection was reduced with IAP in comparison to no intrapartum prophylaxis, but there was no difference in late-onset GBS disease occurrence. Besides GBS, IAP may influence maternal and neonatal infections caused by other pathogens. Moreover, it can also induce GBS and no-GBS pathogen resistance to antibiotics. It therefore seems necessary to replace the current type of GBS screening with GBS DNA PCR intrapartal test--a rapid, highly sensitive and specific method of carrier identification--in order to optimize IAP and, eventually to decrease the rate of early onset GBS disease in neonates.
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We report the case of a late-onset neonatal meningitis by Streptococcus agalactiae (group B Streptococcus - GBS) that was diagnosed with a latex agglutination assay (on cerebrospinal fluid, CSF), as well as by using, for the first time, Xpert GBS (Cepheid, US) on CSF. Due to empirical antibiotics given before sampling, both CSF and blood culture were negative, so indirect diagnostics was crucial. Moreover, the Xpert GBS assay, performed according to an off label, modified protocol (the system is designed for GBS-carriage intrapartum screening, based on a completely automated real time-Polymerase Chain Reaction) quickly detected the organism’s genome target. Although further investigation on this test’s performace on CSF is required, then, we trust it may be a promising, quick and precise diagnostic method for GBS infections in newborns.
Article
Background Management of prelabour rupture of membranes at term (37 weeks gestation or later) (TPROM) remains complicated in the absence of a rapid assay for group B streptococcus (GBS) colonisation. AimsTo evaluate the accuracy and clinical utility of a commercial PCR assay, compared with culture, for detection of GBS colonisation in pregnant women presenting with TPROM. MethodsA prospective study of women presenting with TPROM conducted in a large tertiary hospital (Westmead Hospital, Australia). Five hundred and seventy-four consecutive women with TPROM were enrolled between July 2006 and November 2007. Paired low vaginal and anal swabs were collected from women presenting with TPROM for PCR and culture on GBS selective agar following broth enrichment. Primary outcomes were sensitivity and specificity of PCR compared with GBS selective enrichment culture. Secondary analyses included comparison with a historical but otherwise similar cohort regarding clinical utility, maternal and neonatal outcomes. ResultsPCR sensitivity and specificity were 89.0% (95% CI – 82.8–93.6%) and 97.9% (95% CI – 96.0–99.0%), respectively, compared with culture. 72.3% of women were aware of their GBS PCR status within 3 h of presentation. Compared with the historical cohort, PCR reduced the requirement for intrapartum antibiotics by 25.6% (P < 0.001). There were no significant differences in maternal outcomes or combined rates of admissions to neonatal intensive care or special care nursery. Conclusions Group B streptococcus PCR is an accurate, rapid, safe and practical alternative to culture for detection of GBS colonisation in pregnant women at the time of TPROM. This method has the potential advantage to reduce costs associated with length of hospital stay.
Article
Group B streptococci (GBS) are a leading cause of infectious neonatal morbidity and mortality. Timely and accurate identification of colonized pregnant women is imperative to implement intrapartum antibioprophylaxis (IAP) to reduce the risk of early neonatal sepsis. Current guidelines recommend screening for GBS carriage with vaginal-rectal cultures. However, cultures require 24-72 h, thus precluding their use for intrapartum screening and these are only performed at 35-37 weeks gestation. New rapid molecular-based tests can detect GBS within hours. They have the potential to be used intrapartum and to allow for selective IAP in women carrying GBS. An advantage is that they can sometimes be performed by non-laboratory staff in the labor suite, thus avoiding delays in sample transfers to the microbiology laboratory. Another possible use of molecular-based assays is for the diagnosis of neonatal sepsis, where tests with a short turnaround time and high sensitivity and specificity are crucial. In this situation, the detection of microorganisms once antibiotic therapy has already been started is important, as treatment is started immediately once sepsis is suspected without waiting for microbiological confirmation. In this article, we discuss the state-of-the-art molecular-based tests available for GBS screening during pregnancy, as well as their implications for IAP for the diagnosis and prevention of neonatal sepsis.
Article
Abstract Objective The objective of the study was to analyze the diagnostic accuracy of a commercial real-time polymerase chain reaction (PCR) assay for group B streptococcus (GBS) colonization status and to compare results of the intrapartum PCR with the antepartum conventional GBS culture in Japanese pregnant women. Methods This prospective observational study enrolled Japanese pregnant women at 35-37 weeks' gestation. Paired recto-vaginal swabs were obtained for PCR and conventional culture, both at 35-37 weeks' gestation and at admission for delivery. Performance of PCR was analyzed by comparing with the culture results. Furthermore, using the intrapartum culture results as the gold standard, the test of both the antepartum culture and the intrapartum PCR were characterized. Results We prospectively enrolled 79 pregnant women at 35-37 weeks' gestation and the intrapartum results were obtained from 73 of those women. The sensitivity of PCR was 86.2% and concordance rate with the conventional culture was 96.7% overall. Compared with the intrapartum culture, the sensitivity and the specificity of the intrapartum PCR were 83.3% and 98.4%, respectively, while the sensitivity and the specificity of the antepartum culture were 100.0% and 95.1%. Conclusions The intrapartum real-time PCR assay for GBS screening has the accuracy similar to the antepartum conventional culture method.
Article
Group B Streptococcus (GBS) is a leading cause of neonatal bacterial infections in developed countries. Early-onset disease (EOD) occurs at day 0-6 and late-onset disease occurs at day 7-89. Currently, the prevention of EOD relies upon intrapartum antibiotic prophylaxis (IAP) given to women who are GBS positive at prenatal screening or women with risk factors for EOD. Although successfully implemented, IAP has not fully eradicated EOD, and incidence rates of late-onset disease remain unchanged. Furthermore, antibiotic resistance may result from widespread antibiotic use. New prophylactic strategies are therefore of critical importance. A vaccine active against GBS, administered during pregnancy and combined with targeted IAP, could overcome these problems and reduce the mortality and morbidity associated with invasive diseases.
Being born preterm (prior to 37 weeks of completed gestation) is the leading cause of childhood death up to five years of age, and is responsible for the demise of around one million preterm infants each year. Rates of prematurity, which range from approximately 5 to 18% of births, are increasing in most countries. Babies born extremely preterm (less than 28 weeks’ gestation) and in particular, in the periviable (200/7 – 256/7 weeks) period, are at the highest risk of death, or the development of long-term disabilities. The perinatal care of extremely preterm infants and their mothers raises a number of clinical, technical, and ethical challenges. Focusing on ‘micropremmies’, or those born in the periviable period, the present paper provides an update regarding the aetiology and impacts of periviable preterm birth, advances in the antenatal, intrapartum, and acute post-natal management of these infants, and a review of counselling/support approaches for engaging with the infant’s family. It concludes with an overview of emerging technology that may assist in improving outcomes for this at-risk population.
Article
Neonatal group B streptococcal disease has become less common but still constitutes a major cause ofmorbidity andmortality. Around the world, a variety of preventive strategies are in place with varying degrees of implementation and success. This article reviews these approaches and looks to the future. © 2014 by the American Academy of Pediatrics. All rights reserved.
Article
Résumé Objectif Analyser les données issues de la littérature et formuler des recommandations sur la prise en charge des parturientes en vue de prévenir l'infection néonatale à streptocoques du groupe B d'apparition précoce. Parmi les révisions clés que renferme la présente directive clinique mise à jour, on trouve des modifications quant aux recommandations en ce qui concerne les schémas posologiques d'antibioprophylaxie, les épreuves de sensibilité et la prise en charge des femmes présentant une rupture prématurée des membranes. Issues Parmi les issues maternelles évaluées, on trouvait l'exposition aux antibiotiques au cours de la grossesse et du travail, ainsi que les complications associées à l'administration d'antibiotiques. Les issues néonatales associées aux taux d'infection néonatale à streptocoques du groupe B d'apparition précoce ont été évaluées. Résultats La littérature publiée a été récupérée par l'intermédiaire de recherches menées dans PubMed, CINAHL et The Cochrane Library entre janvier 1980 et juillet 2012, au moyen d'un vocabulaire contrôlé et de mots clés appropriés (« group B streptococcus », « antibiotic therapy », « infection », « prevention »). Les résultats ont été restreints aux analyses systématiques, aux essais comparatifs randomisés / essais cliniques comparatifs et aux études observationnelles. Aucune restriction n'a été appliquée en matière de date ou de langue. Les recherches ont été mises à jour de façon régulière et intégrées à la directive clinique jusqu'en mai 2013. La littérature grise (non publiée) a été identifiée par l'intermédiaire de recherches menées dans les sites Web d'organismes s'intéressant à l'évaluation des technologies dans le domaine de la santé et d'organismes connexes, dans des collections de directives cliniques, dans des registres d'essais cliniques et auprès de sociétés de spécialité médicale nationales et internationales. Valeurs La qualité des résultats est évaluée au moyen des critères décrits dans le rapport du Groupe d'étude canadien sur les soins de santé préventifs ( Tableau 1 ). Avantages, désavantages et coûts Les recommandations que renferme la présente directive clinique sont conçues de façon à aider les cliniciens à identifier et à assurer la prise en charge des grossesses exposées à un risque d'infection néonatale à streptocoques du groupe B, en vue d'optimiser les issues maternelles et périnatales. Aucune analyse de rentabilité n'est fournie. Déclaration sommaire Nous disposons de bonnes données (issues d'essais comparatifs randomisés) indiquant que, chez les femmes présentant une rupture prématurée des membranes à terme qui sont colonisées par des streptocoques du groupe B, le déclenchement du travail entraîne une baisse des taux d'infection néonatale (I). Aucune donnée ne permet de soutenir que, dans une telle situation clinique, la prise en charge non interventionniste permet l'obtention de bonnes issues néonatales. Recommandations • 1.Offrir, à toutes les femmes, un dépistage de la colonisation par des streptocoques du groupe B à 35 - 37 semaines de gestation au moyen d'une mise en culture effectuée à partir d'un écouvillonnage du vagin, en premier lieu, et du rectum par la suite (au-delà du sphincter anal). (II-1A) Cette approche s'applique également aux femmes chez qui une césarienne est planifiée, et ce, en raison de leur risque de connaître un travail ou une rupture des membranes avant la date prévue de la césarienne (II-2B). • 2.En raison de l'association entre une forte colonisation et l'infection néonatale d'apparition précoce, administrer une antibioprophylaxie intraveineuse visant les streptocoques du groupe B dans les cas suivants, au moment de l'apparition du travail ou de la rupture des membranes: • •toutes les femmes ayant obtenu des résultats positifs (indiquant la présence de streptocoques du groupe B) dans le cadre du dépi- stage par mise en culture d'un écouvillonnage vaginal / rectal mené à 35 - 37 semaines de gestation (II-2B); • •toute femme ayant déjà accouché d'un enfant présentant une infection à streptocoques du groupe B (II-3B); • •toute femme ayant présenté une bactériurie à streptocoques du groupe B documentée (peu importe le taux d'unités formatrices de colonies) dans le cadre de la grossesse en cours (II-2A). • 3.Administrer une antibioprophylaxie intraveineuse visant les strep- tocoques du groupe B pendant un minimum de 48 heures à toutes les femmes se trouvant à < 37 semaines de gestation et con- naissant un travail ou une rupture des membranes, sauf lorsqu'un résultat négatif a été obtenu au cours des cinq semaines précé- dentes dans le cadre d'un test rapide fondé sur les acides nucléi- ques ou d'un dépistage par mise en culture d'un écouvillonnage vaginal / rectal (II-3A). • 4.Administrer (par voie intraveineuse) des antibiotiques à large spectre ciblant la chorioamnionite et les streptocoques du groupe B à toutes les femmes qui présentent une fièvre intra- partum et des symptômes de chorioamnionite (sans égard à l'âge gestationnel ni à l'état quant aux streptocoques du groupe B) (II-2A). • 5.Demander la tenue d'une épreuve de sensibilité aux antibiotiques chez les femmes qui ont obtenu des résultats positifs en ce qui concerne la présence de streptocoques du groupe B, à la suite d'un dépistage urinaire et de la mise en culture d'un écouvillonnage vaginal/rectal, et que l'on soupçonne être exposées à un risque considérable d'anaphylaxie attribuable à la pénicilline (II-1A). • 6.Lorsqu'une femme présentant une rupture prématurée des mem- branes ≥ 37 semaines de gestation obtient des résultats positifs (au dépistage par mise en culture d'un écouvillonnage vaginal / rectal) indiquant la présence de streptocoques du groupe B, qu'elle a connu une bactériurie à streptocoques du groupe B pendant la grossesse en cours ou qu'elle a déjà accouché d'un enfant atteint d'une infection à streptocoques du groupe B, administrer une anti- bioprophylaxie intraveineuse visant les streptocoques du groupe B. La tenue immédiate d'un accouchement obstétrical (tel que le déclenchement du travail) s'avère indiquée, comme le décrit la directive clinique intitulée « Déclenchement du travail » qui a été publiée par la Société des obstétriciens et gynécologues du Canada en septembre 2013 (II-2B). • 7.À 2 37 semaines de gestation, lorsque le statut quant à la coloni- sation par des streptocoques du groupe B est inconnu, qu'une mise en culture n'a pas été menée à 35 - 37 semaines de gestation (ou que les résultats d'une telle mise en culture ne sont pas disponibles) et que les membranes sont rompues depuis plus de 18 heures, administrer une antibioprophylaxie intraveineuse visant les strepto- coques du groupe B (II-2B). • 8.Lorsque, chez une femme présentant une rupture prématurée des membranes à < 37 semaines de gestation, les résultats du dépi- stage des streptocoques du groupe B par mise en culture sont inconnus ou positifs, administrer une antibioprophylaxie intra- veineuse visant les streptocoques du groupe B pendant 48 heures, ainsi que d'autres antibiotiques lorsque cela s'avère indiqué, en attendant la mise en œuvre spontanée ou obstétricalement indiquée du travail (II-3B).
Article
Prevention of perinatal Group B Streptococcus (GBS) transmission is crucial in our effort to prevent Early-onset GBS disease. Here, we established the performance of the Revogene GBS DS assay for the detection of group B streptococcus on intrapartum vaginal samples in a laboratory environment using a prospective non-interventional study design. Intrapartum vaginal swabs were enriched using a selective culture method which served as study reference method. Overall, 119 patients were enrolled with an antenatal and intrapartum Group B Streptococcus colonization prevalence of 12.9% and 11.8%, respectively. Compared to intrapartum culture, the Revogene GBS DS assay had a sensitivity of 92.9% and a specificity of 99.1%, while the antenatal culture displayed a sensitivity 78.6% of and specificity of 96.2%. The Revogene GBS DS assay displayed an acceptable performance according to the European Group B Streptococcus consensus recommendations. Complementary studies in clinical practice are needed to confirm these findings.
Article
Background: Screening-based and risk-based strategies are the 2 strategies for preventing group B streptococcus (GBS) diseases in neonates. We aimed to compare the effects of these 2 strategies in reducing the incidence of early-onset GBS sepsis (GBS-EOS) and their effects on the incidence of non-GBS sepsis. Methods: PubMed, Embase, Web of Science and The Cochrane Central Register of Controlled Trials were searched for the period from January 1, 1996, to December 31, 2018. Randomized controlled trials and cohort studies that compared the effects of risk-based and screening-based strategies were eligible for the meta-analysis. The I statistic was used for assessing the statistical heterogeneity across studies. Pooled relative risks (RRs) and corresponding 95% confidence intervals (CIs) were calculated using the random effects model. Results: There were 18 cohort studies comparing the incidence of GBS-EOS between the 2 strategies, involving a total of 604,869 newborns and 791 GBS-EOS cases. The heterogeneity across studies was moderate (I = 45%), and the pooled analysis yielded a 55% decreased risk of GBS-EOS for screening-based versus risk-based strategy (RR = 0.45; 95% CI: 0.34-0.59). For total early onset non-GBS sepsis (non-GBS-EOS), 7 studies with low heterogeneity (I = 18%) had a pooled RR of 0.91 (95% CI: 0.74-1.11), whereas for ampicillin resistant Escherichia coli-EOS, a subgroup of non-GBS-EOS, 3 studies with very low heterogeneity (I = 0%) had a pooled RR of 1.28 (95% CI: 0.74-2.21) for screening-based strategy compared with risk-based strategy. Conclusions: Compared with risk-based strategy, screening-based prophylaxis was associated with a reduced risk of GBS-EOS.
Article
Problem: Despite the introduction of preventive guidelines, no decrease in the incidence of early onset infection was observed. Background: Early onset group B streptococcal (EOGBS) infection is an important cause of neonatal morbidity and mortality. Aim: Our study was conducted to determine adherence to three guideline-based group B streptococcus (GBS) preventive strategies. Methods: A prospective experimental study clustered by obstetric collaboration region was performed between March 2013 and August 2014 among midwives, obstetricians and paediatricians in the Netherlands. At baseline, the three regions operated according to the Dutch preventive strategy (founded on the risk-based strategy) in order to prevent EOGBS infection, whereas in the study period they followed either the risk-based, the combination or the Dutch strategy. Adherence was measured prospectively per pregnant woman, using predefined core elements of each preventive strategy: identification of risk factors, maternal GBS screening, application of intrapartum antibiotic prophylaxis and observation of the child. Data about adherence to the core elements were collected from medical records, maternal questionnaires and laboratory test results. Findings: In the three regions, a total of 121 care providers and 1562 women participated. We found an overall adherence of 90% to the risk-based strategy, 57% to the combination strategy and 89% to the Dutch strategy. Adherence to a strategy in case women had EOGBS risk factors was below 20% in all strategies. Discussion: The majority of women with EOGBS risk factors did not receive the care prescribed by any of three preventive strategies and were not treated optimally. Conclusion: The risk-based and the Dutch strategy are the recommended strategies for implementation.
Article
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Introduction: Neonatal sepsis remains a serious and potentially fatal illness. Intrapartum antibiotic prophylaxis (IAP) prevents group B streptococcal (GBS) early-onset sepsis. The optimal duration of IAP (adequate IAP) to reduce vertical transmission of GBS has been debated. Understanding the mechanism of action of IAP may help in minimizing neonatal evaluation and unnecessary antibiotic use. Areas covered: In recent years, several studies on pharmacokinetics and clinical use of IAP have been published. Although penicillin and ampicillin are the most preferred antibiotics, the clinical efficacy of non-beta-lactam antibiotics, including clindamycin and vancomycin, used in cases of penicillin anaphylaxis-associated allergy, remains debatable. This is a narrative review of the literature regarding the impact of “inadequate” IAP on the clinical management of women and newborns. Expert opinion: Recent evidence suggests that “inadequate” IAP with beta-lactams is more effective in preventing vertical transmission of GBS than previously thought. Newborns exposed to intrapartum beta-lactams and who are asymptomatic at birth are likely uninfected, irrespective of IAP duration before delivery. Hence, we may abandon the concept of “inadequate” IAP with beta-lactams in early-onset GBS sepsis, relying primarily on clinical signs observed at birth for managing IAP-exposed neonates.
Article
Aim Global screening strategies for Group B Streptococcus (GBS) include risk‐ or culture‐based methods to guide intrapartum prophylaxis. In Western Australia (WA), antenatal culture‐based screening is routine, however, numerous culture methods exist, in addition to molecular methods. We aimed to assess the comparability of research and diagnostic screening approaches. Methods and Results Vaginal and rectal swabs were self‐collected by pregnant women (n=531) from King Edward Memorial Hospital, WA, in parallel to routine screening (35‐37 weeks gestation). Research methods involved culture (Strep B Carrot Broth™ and StrepB CHROMagar™) and molecular methods (real‐time PCR), and were compared to routine diagnostic screening (Lim Broth and Granada agar). Overall, GBS detection was comparable between research and diagnostic approaches (3‐5% discrepancy, kappa=0·76). Specificity/sensitivity of Carrot Broth™ was 100%/~89%, while CHROMagar™ was 73%/100%, respectively. Direct PCR was unable to detect GBS in ~18% of specimens which were culture positive, however, it exhibited 100% specificity. Conclusions This clinical evaluation of GBS screening methods provides support for current practice. Significance and Impact Although CHROM was highly sensitive, further testing is recommended due to a high false positive rate. Molecular assays are useful for rapid detection, however, low titre samples may require additional enrichment prior to molecular analysis to improve sensitivity. This article is protected by copyright. All rights reserved.
Article
Objective: To review the evidence in the literature and to provide recommendations on the management of pregnant women in labour for the prevention of early-onset neonatal group B streptococcal disease. The key revisions in this updated guideline include changed recommendations for regimens for antibiotic prophylaxis, susceptibility testing, and management of women with pre-labour rupture of membranes. Outcomes: Maternal outcomes evaluated included exposure to antibiotics in pregnancy and labour and complications related to antibiotic use. Neonatal outcomes of rates of early-onset group B streptococcal infections are evaluated. Evidence: Published literature was retrieved through searches of MEDLINE, CINAHL, and The Cochrane Library from January 1980 to July 2012 using appropriate controlled vocabulary and key words (group B streptococcus, antibiotic therapy, infection, prevention). Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. There were no date or language restrictions. Searches were updated on a regular basis and incorporated in the guideline to May 2013. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies. Values: The quality of evidence in this document was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care (Table 1). Benefits, harms, and costs: The recommendations in this guideline are designed to help clinicians identify and manage pregnancies at risk for neonatal group B streptococcal disease to optimize maternal and perinatal outcomes. No cost-benefit analysis is provided. Summary statement: There is good evidence based on randomized control trial data that in women with pre-labour rupture of membranes at term who are colonized with group B streptococcus, rates of neonatal infection are reduced with induction of labour (I). There is no evidence to support safe neonatal outcomes with expectant management in this clinical situation. Recommendations:
Article
To review the evidence in the literature and to provide recommendations on the management of pregnant women in labour for the prevention of early-onset neonatal group B streptococcal disease. The key revisions in this updated guideline include changed recommendations for regimens for antibiotic prophylaxis, susceptibility testing, and management of women with pre-labour rupture of membranes.
Article
Objective: To evaluate the efficacy and safety of dequalinium chloride (DQC; 10 mg vaginal tablets), administered shortly prior to delivery in women with group B streptococcus (GBS) infection. Methods: This observational, longitudinal, and prospective study involved 201 pregnant women at term, potentially carriers of GBS bacteria, scheduled for induction with oxytocin and with no premature rupture of amniotic membranes. Results: A total of 163 women (81.09%) tested positive for GBS in their first vaginal swab (pre-DQC administration). In their second swab, post-DQC administration, 48 women were positive (23.88%) and 153 (76.12%) were negative. The number of GBS-colonized women after the administration of DQC was reduced by 57.21%. In the third swab, postpartum, 57 women were positive (28.35%). None of the newborns were positive for GBS in the oropharynx swab. The median DQC exposure time was 9.98 hours. Adverse events associated with the prophylactic treatment were reported in five women (vulvovaginal irritation). Conclusions: The administration of a single vaginal tablet of 10 mg DQC the day before induction reduced the number of GBS-colonized women by 57.21%, causing no maternal and perinatal adverse events.
Article
Retrospective analysis of Streptococcus agalactiae antibiotic susceptibility isolated in 2010-2013 was performed. Penicillin was still the first-line antibiotic. Due to the high percentage of strains resistant to erythromycin and clindamycin empirical treatment with these antibiotics may not be effective. Lower resistance rate to erythromycin and clindamycin among strains isolated from infected pregnant women and newborns were observed than among strains isolated from samples from patients hospitalized in other departments (29% and 47% v. 46% and 63%). The increasing resistance rate might give a rise to a new epidemiological situation.
Chapter
Infection in pregnancy is associated with pre term birth, intra uterine death and transmission of infection to the fetus and neonate. Common infections such as urinary tract, respiratory tract and gastrointestinal tract infections, candidiasis, bacterial vaginosis, and sexually transmitted infections assume greater importance in pregnancy as complications may additionally impact on fetal and neonatal health. Antenatally, these may present clinically as maternal sepsis, chorioamnionitis, or hydrops fetalis. Post-partum manifestations include endometritis, mastitis, maternal and neonatal sepsis syndromes. Pathogens of particular interest in pregnancy include: Chlamydia trachomatis, Neisseria gonorrhoeae, Mycobacterium tuberculosis, Streptococcus pyogenes, Streptococcus agalactiae, Treponema pallidum, Listeria monocytogenes, Toxoplasma gondii, Trichomonas vaginalis, Plasmodium spp, Human Herpes Simplex Viruses 1 and 2, Varicella Zoster Virus, Cytomegalovirus, Parvovirus B19, Rubella, and Human Immunodeficiency Virus. This chapter reviews various infectious presentations in both mother and child, focussing on both antenatal and postnatal periods, and then reviews key pathogens associated with the burden in infection during the perinatal period, with consideration of their microbiology, transmission, diagnosis, epidemiology, pathogenesis, presentation, treatment, prevention, and public health importance.
Article
Objective: To estimate the cost-effectiveness of universal group B streptococci (GBS) screening in women with a singleton pregnancy planning a repeat cesarean delivery. Methods: We conducted a decision analysis from a health care perspective to compare the cost-effectiveness of GBS screening for women planning a repeat cesarean delivery. With universal screening, all GBS-positive women who labored before a scheduled cesarean delivery received antibiotic prophylaxis. With no screening, women who presented in labor received antibiotics based on risk-based criteria. Neonates born to women colonized with GBS were at risk for early-onset GBS disease, disability, and death. We assumed a GBS prevalence of 25%, that 26.6% of women labored between 35 weeks of gestation and their scheduled time for cesarean delivery, and that 3.3% who planned a repeat cesarean delivery instead delivered vaginally. The primary outcome was cost per neonatal quality-adjusted life-year gained, with a cost-effectiveness threshold of $100,000 per quality-adjusted life-year. Neonatal quality of life was assessed using five health states (healthy, mild, moderate, or severe disability, and death) with a life expectancy of 79 years for healthy neonates. One-way sensitivity and Monte Carlo analyses were used to evaluate the results. Results: In the base case, universal GBS screening in women planning a repeat cesarean delivery was not cost-effective compared with no screening, costing $114,445 per neonatal quality-adjusted life-year gained. The cost to prevent an adverse outcome from GBS exceeded $400,000. If greater than 28% of women were GBS-positive, greater than 29% labored before their scheduled delivery, or greater than 10% delivered vaginally, universal screening became cost effective. Conclusion: Universal GBS screening in women with a singleton pregnancy planning a repeat cesarean delivery may not be cost-effective in all populations. However, in populations with a high GBS prevalence, women at high risk of laboring before their scheduled cesarean delivery, or women who may ultimately opt for a vaginal delivery, GBS screening may be cost effective.
Article
Objectives: The objectives were to evaluate and compare the diagnostic accuracy of a rapid real-time PCR assay at the onset of labor with those of the current antenatal culture-based test at 34-38 weeks gestation for group B Streptococcus (GBS) screening. Materials and methods: A prospective study including all pregnant women admitted for delivery after a 34-week gestation period was conducted in October 2012 at the Grenoble University Hospital Centre. A first culture-based GBS screening test was performed between 34 and 38 weeks of gestation followed by a second screening test at the onset of labor, using a real-time PCR Assay and a culture-based method (gold standard) in order to calculate the diagnostic accuracy. Results: One hundred an fifty-seven patients were enrolled. The sensitivity was 94.4% (95% CI, 72.7-99.9%) with intrapartum PCR assay and 50% (95% CI, 26-74%) with antepartum culture. Prevalence of GBS colonization was 7.6% with the antepartum culture method, 11.5% with intrapartum culture and 16.6% by using PCR-test. Conclusion: Intrapartum PCR shows a much higher sensitivity compared to the antepartum culture-based screening mainly due to variations in GBS colonization and could allow us to target patients requiring intrapartum antibiotic prophylaxis more effectively.
Article
Objective: To evaluate the effect of a rapid PCR-based group B streptococcus (GBS) test on length of stay in hospital among newborns, antibiotic use, and GBS-early-onset-disease (EOD) incidence. Methods: We conducted a before and after service evaluation including term deliveries between 1st January and 12th November 2014 (6688 deliveries). Length of stay in the hospital, GBS-EOD incidence and antibiotic use were evaluated. Results: We recorded three confirmed and 74 possible cases of GBS-EOD in Phase 1, and 85 possible cases in Phase 2. In newborns with suspected infection, the introduction of the rapid test was related to a decreased length of stay on the pediatric care unit by 1.16 days (p = 0.01), and an increase in the length of stay on the mother-and-baby ward by 1.11 days (p < 0.001). No increase in antibiotics was noted. Conclusion: The introduction of a point of care test was associated with a reduction in length of stay in the pediatric care unit, without an increase in antibiotic use. This test could improve the accuracy of GBS colonization detection, and help to prevent intrapartum transmission as no verified GBS-EOD cases were recorded with the intrapartum PCR algorithm.
Article
Résumé Objectif Analyser les données issues de la littérature et formuler des recommandations sur la prise en charge des parturientes en vue de prévenir l’infection néonatale à streptocoques du groupe B d’apparition précoce. Parmi les révisions clés que renferme la présente directive clinique mise à jour, on trouve des modifications quant aux recommandations en ce qui concerne les schémas posologiques d’antibioprophylaxie, les épreuves de sensibilité et la prise en charge des femmes présentant une rupture prématurée des membranes. Issues Parmi les issues maternelles évaluées, on trouvait l’exposition aux antibiotiques au cours de la grossesse et du travail, ainsi que les complications associées à l’administration d’antibiotiques. Les issues néonatales associées aux taux d’infection néonatale à streptocoques du groupe B d’apparition précoce ont été évaluées. Résultats La littérature publiée a été récupérée par l’intermédiaire de recherches menées dans PubMed, CINAHL et The Cochrane Library entre janvier 1980 et juillet 2012, au moyen d’un vocabulaire contrôlé et de mots clés appropriés (« group B streptococcus », « antibiotic therapy », « infection », « prevention »). Les résultats ont été restreints aux analyses systématiques, aux essais comparatifs randomisés / essais cliniques comparatifs et aux études observationnelles. Aucune restriction n’a été appliquée en matière de date ou de langue. Les recherches ont été mises à jour de façon régulière et intégrées à la directive clinique jusqu’en mai 2013. La littérature grise (non publiée) a été identifiée par l’intermédiaire de recherches menées dans les sites Web d’organismes s’intéressant à l’évaluation des technologies dans le domaine de la santé et d’organismes connexes, dans des collections de directives cliniques, dans des registres d’essais cliniques et auprès de sociétés de spécialité médicale nationales et internationales. Valeurs La qualité des résultats est évaluée au moyen des critères décrits dans le rapport du Groupe d’étude canadien sur les soins de santé préventifs (Tableau 1). Avantages, désavantages et coûts Les recommandations que renferme la présente directive clinique sont conçues de façon à aider les cliniciens à identifier et à assurer la prise en charge des grossesses exposées à un risque d’infection néonatale à streptocoques du groupe B, en vue d’optimiser les issues maternelles et périnatales. Aucune analyse de rentabilité n’est fournie. Déclaration sommaire Nous disposons de bonnes données (issues d’essais comparatifs randomisés) indiquant que, chez les femmes présentant une rupture prématurée des membranes à terme qui sont colonisées par des streptocoques du groupe B, le déclenchement du travail entraîne une baisse des taux d’infection néonatale. (I) Aucune donnée ne permet de soutenir que, dans une telle situation clinique, la prise en charge non interventionniste permet l’obtention de bonnes issues néonatales. Recommandations 1. Offrir, à toutes les femmes, un dépistage de la colonisation par des streptocoques du groupe B à 35 - 37 semaines de gestation au moyen d’une mise en culture effectuée à partir d’un écouvillonnage du vagin, en premier lieu, et du rectum par la suite (au-delà du sphincter anal). (II-1A) Cette approche s’applique également aux femmes chez qui une césarienne est planifiée, et ce, en raison de leur risque de connaître un travail ou une rupture des membranes avant la date prévue de la césarienne. (II-2B) 2. En raison de l’association entre une forte colonisation et l’infection néonatale d’apparition précoce, administrer une antibioprophylaxie intraveineuse visant les streptocoques du groupe B dans les cas suivants, au moment de l’apparition du travail ou de la rupture des membranes : • toutes les femmes ayant obtenu des résultats positifs (indiquant la présence de streptocoques du groupe B) dans le cadre du dépistage par mise en culture d’un écouvillonnage vaginal / rectal mené à 35 - 37 semaines de gestation (II-2B); • toute femme ayant déjà accouché d’un enfant présentant une infection à streptocoques du groupe B (II-3B); • toute femme ayant présenté une bactériurie à streptocoques du groupe B documentée (peu importe le taux d’unités formatrices de colonies) dans le cadre de la grossesse en cours. (II-2A) 3. Administrer une antibioprophylaxie intraveineuse visant les streptocoques du groupe B pendant un minimum de 48 heures à toutes les femmes se trouvant à < 37 semaines de gestation et connaissant un travail ou une rupture des membranes, sauf lorsqu’un résultat négatif a été obtenu au cours des cinq semaines précédentes dans le cadre d’un test rapide fondé sur les acides nucléiques ou d’un dépistage par mise en culture d’un écouvillonnage vaginal / rectal. (II-3A) 4. Administrer (par voie intraveineuse) des antibiotiques à large spectre ciblant la chorioamnionite et les streptocoques du groupe B à toutes les femmes qui présentent une fièvre intrapartum et des symptômes de chorioamnionite (sans égard à l’âge gestationnel ni à l’état quant aux streptocoques du groupe B). (II-2A) 5. Demander la tenue d’une épreuve de sensibilité aux antibiotiques chez les femmes qui ont obtenu des résultats positifs en ce qui concerne la présence de streptocoques du groupe B, à la suite d’un dépistage urinaire et de la mise en culture d’un écouvillonnage vaginal/rectal, et que l’on soupçonne être exposées à un risque considérable d’anaphylaxie attribuable à la pénicilline. (II-1A) 6. Lorsqu’une femme présentant une rupture prématurée des membranes à ≥ 37 semaines de gestation obtient des résultats positifs (au dépistage par mise en culture d’un écouvillonnage vaginal / rectal) indiquant la présence de streptocoques du groupe B, qu’elle a connu une bactériurie à streptocoques du groupe B pendant la grossesse en cours ou qu’elle a déjà accouché d’un enfant atteint d’une infection à streptocoques du groupe B, administrer une antibioprophylaxie intraveineuse visant les streptocoques du groupe B. La tenue immédiate d’un accouchement obstétrical (tel que le déclenchement du travail) s’avère indiquée, comme le décrit la directive clinique intitulée « Déclenchement du travail » qui a été publiée par la Société des obstétriciens et gynécologues du Canada en septembre 2013. (II-2B) 7. À ≥ 37 semaines de gestation, lorsque le statut quant à la colonisation par des streptocoques du groupe B est inconnu, qu’une mise en culture n’a pas été menée à 35 - 37 semaines de gestation (ou que les résultats d’une telle mise en culture ne sont pas disponibles) et que les membranes sont rompues depuis plus de 18 heures, administrer une antibioprophylaxie intraveineuse visant les streptocoques du groupe B. (II-2B) 8. Lorsque, chez une femme présentant une rupture prématurée des membranes à < 37 semaines de gestation, les résultats du dépistage des streptocoques du groupe B par mise en culture sont inconnus ou positifs, administrer une antibioprophylaxie intraveineuse visant les streptocoques du groupe B pendant 48 heures, ainsi que d’autres antibiotiques lorsque cela s’avère indiqué, en attendant la mise en œuvre spontanée ou obstétricalement indiquée du travail. (II-3B)
Article
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Current guidelines for prevention of group B streptococcus (GBS) early-onset infection recommend to administer antibiotic during labor at least 4 h prior to delivery (adequate prophylaxis). We aimed to determine if neonatal GBS colonization may be significantly decreased in case of inadequate (<4 h) duration of ampicillin prophylaxis. In prospective, cohort study, 167 infants born to 167 GBS culture-positive mothers without additional risk factors were enrolled. Cultures were collected both, at 10-24 h after birth (admission) and at discharge. Among 137 infants born to mothers who received inadequate prophylaxis, 5 (3.6%, C.I. = 0.5-6.8) were colonized (≥1 sites) at admission, at discharge, or both, at admission and discharge. Eighty-two women received prophylaxis <2 h before delivery and two infants (2.4%) were colonized at discharge. Eighteen (60.0%, C.I. = 42.5-77.5) of 30 infants who were not exposed to prophylaxis were colonized at admission or both, at admission and discharge. Colonization was significantly more frequent among infants born to untreated mothers with respect to infants born to women who received inadequate prophylaxis (either <2 or <4 h). In this selected group, inadequate prophylaxis significantly interrupted vertical colonization. This effect was evident even if prophylaxis started <2 h before delivery.
Article
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The objective of this study was to determine the reliability of the real-time PCR assay for determining the group B Streptococcus (GBS) status of women in labor. In this prospective study we compared the results of culture and PCR testing of vaginal and rectal samples collected by nursing staff when women were in labor. Patients' charts were also reviewed to obtain relevant information about pregnancy risk factors. Our results demonstrated a sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 90.5%, 96.1%, 86.4%, and 97.4%, respectively, for rapid PCR. Of the 196 women evaluated, 29 (14.8%) presented with unknown GBS status, 11 (37.9%) of whom received unnecessary intrapartum antibiotics. The rapid real-time PCR test was robust and was able to reliably detect the presence of GBS in women in labor within 1 h of specimen submission to the laboratory. We recommend that the rapid PCR test be targeted to women who present in labor with unknown GBS status. In cases where the laboratory does not offer 24-h availability of testing, sample collection followed by PCR testing the next morning is still valuable and provides reliable results 24 to 48 h faster than culture and will aid appropriate decision-making regarding continuing or stopping antibiotics for neonates of women with unknown GBS status.
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Group B streptococcal disease is one of the most common infections in the first week after birth. In 2002, national guidelines recommended universal late antenatal screening of pregnant women for colonization with group B streptococcus to identify candidates for intrapartum chemoprophylaxis. We evaluated the implementation of the guidelines in a multistate, retrospective cohort selected from the Active Bacterial Core surveillance, a 10-state, population-based system that monitors invasive group B streptococcal disease. We abstracted data from the labor and delivery records of a stratified random sample of live births and of all cases in which the newborn had early-onset group B streptococcal disease (i.e., disease in infants <7 days of age) in 2003 and 2004. We compared our results with those from a study with a similar design that evaluated screening practices in 1998 and 1999. We abstracted records of 254 births in which the infant had group B streptococcal disease and 7437 births in which the infant did not. The rate of screening for group B streptococcus before delivery increased from 48.1% in 1998-1999 to 85.0% in 2003-2004; the percentage of infants exposed to intrapartum antibiotics increased from 26.8% to 31.7%. Chemoprophylaxis was administered in 87.0% of the women who were positive for group B streptococcus and who delivered at term, but in only 63.4% of women with unknown colonization status who delivered preterm. The overall incidence of early-onset group B streptococcal disease was 0.32 cases per 1000 live births. Preterm infants had a higher incidence of early-onset group B streptococcal disease than did term infants (0.73 vs. 0.26 cases per 1000 live births); however, 74.4% of the cases of group B streptococcal disease (189 of 254) occurred in term infants. Missed screening among mothers who delivered at term accounted for 34 of the 254 cases of group B streptococcal disease (13.4%). A total of 61.4% of the term infants with group B streptococcal disease were born to women who had tested negative for group B streptococcus before delivery. Recommendations for universal screening were rapidly adopted. Improved management of preterm deliveries and improved collection, processing, and reporting of culture results may prevent additional cases of early-onset group B streptococcal disease.
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The objective of the study was to determine the rate of early onset group B streptococcus (EOGBS) infection in Utah and identify potential areas of failure in EOGBS prevention. We queried the microbiology records of Intermountain Healthcare for infants with culture-confirmed EOGBS between 1 January 2002 and 31 May 2006 and calculated rates of EOGBS per 1000 deliveries. We reviewed the infant and maternal records of each EOGBS case to identify possible failures in EOGBS prevention. There were 54 cases of EOGBS among the 127 205 births (0.42/1000 births). Of all, 12 were preterm. Of the 39 (93%) women prenatally screened for GBS, 31 (79%) had negative results and 7/8 (88%) women with positive prenatal GBS screens either did not receive intrapartum antibiotic prophylaxis (IAP) or received inadequate IAP. Of the 54 infants with EOGBS, 3 (6%) died. Utah's rates of EOGBS were higher than the national average. Factors associated with EOGBS include missed screening opportunities, inadequate IAP, and false-negative maternal GBS culture.
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Guidelines issued in 1996 in the United States recommend either screening of pregnant women for group B streptococcal colonization by means of cultures (screening approach) or assessing clinical risk factors (risk-based approach) to identify candidates for intrapartum antibiotic prophylaxis. In a multistate retrospective cohort study, we compared the effectiveness of the screening and risk-based approaches in preventing early-onset group B streptococcal disease (in infants less than seven days old). We studied a stratified random sample of the 629,912 live births in 1998 and 1999 in eight geographical areas where there was active surveillance for group B streptococcal infection, including all births in which the neonate had early-onset disease. Women with no documented culture for group B streptococcus were considered to have been cared for according to the risk-based approach. We studied 5144 births, including 312 in which the newborn had early-onset group B streptococcal disease. Antenatal screening was documented for 52 percent of the mothers. The risk of early-onset disease was significantly lower among the infants of screened women than among those in the risk-based group (adjusted relative risk, 0.46; 95 percent confidence interval, 0.36 to 0.60). Because women whose providers had no strategy for prophylaxis may have been misclassified in the risk-based group, we excluded all women with risk factors and adequate time for prophylaxis who did not receive antibiotics. The adjusted relative risk of early-onset disease associated with the screening approach in this secondary analysis was similar--0.48 (95 percent confidence interval, 0.37 to 0.63). Routine screening for group B streptococcus during pregnancy prevents more cases of early-onset disease than the risk-based approach. Recommendations that endorse both strategies as equivalent warrant reconsideration.
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Current prevention of infection due to group B Streptococcus (GBS) involves giving intrapartum antibiotics to women on the basis of either antenatal culture colonization status or presence of risk factors. We prospectively compared the performance characteristics of a rapid molecular diagnostic test (IDI-Strep B; Infectio Diagnostic) with culture for intrapartum GBS detection after 36 weeks' gestation in 5 North American centers during the period September 2001-May 2002. Antenatal GBS screening was done according to the usual practice of participating hospitals. Two combined vaginal/anal specimens were obtained from participants during labor by use of standard techniques and processed by the same laboratories that processed the antenatal specimens. Each swab sample was processed simultaneously by culture and with IDI-Strep B. The collected specimens were randomized for order of testing of the swab samples by culture or the rapid test. Of enrolled women, 803 (91.1%) were eligible for analysis. The overall intrapartum GBS colonization rate by culture was 18.6% (range, 9.1%-28.7%). Compared with intrapartum culture, the molecular test had a sensitivity of 94.0% (range, 90.1%-97.8%), specificity of 95.9% (range, 94.3%-97.4%), positive predictive value of 83.8% (range, 78.2%-89.4%), and negative predictive value of 98.6% (range, 97.7%-99.5%). The molecular test was superior to antenatal cultures (sensitivity, 94% vs. 54%; P<.0001) and prediction of intrapartum status on the basis of risk factors (sensitivity, 94% vs. 42%; P<.0001). Use of this test for determination of GBS colonization during labor is highly sensitive and specific and may lead to a further reduction in rates of neonatal GBS disease.
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With the widespread implementation of intrapartum antibiotic prophylaxis (IAP), the rate of early-onset neonatal sepsis and meningitis caused by Streptococcus agalactiae (group B streptococcus [GBS]) has decreased dramatically, especially in term infants. However, cases of GBS disease continue to occur despite IAP and incur significant morbidity and mortality. Inaccurate screening results, improper implementation of IAP, or antibiotic failure all may contribute to persistent disease. To determine if clinical, procedural, or microbiologic factors influenced persistent early-onset GBS disease (EOGBS) cases in a single large maternity service after the institution of a screening-based protocol for IAP. Retrospective review of all cases of culture-proven EOGBS at the Brigham and Women's Hospital (Boston, MA) from 1997 to 2003. Serotyping and surface protein analyses were performed on available disease isolates. A total of 67260 infants were live-born during this period. Twenty-five cases of EOGBS (0.37 of 1000 live births) were identified. The overall incidence of EOGBS progressively decreased with different approaches to IAP. Of the 25 cases identified after institution of a screening-based protocol, 17 (68%) occurred in term infants (1 death), and 8 (32%) occurred in preterm infants (3 deaths). Among the mothers of term infants, 14 of 17 (82%) had been screened GBS negative; 1 was GBS unknown. More than half of the mothers of term infants who had screened GBS negative (8 of 14) had intrapartum risk factors for neonatal infection but did not receive antibiotics before delivery. Ten of the 17 term infants were evaluated for infection because of clinical signs of illness, and the remainder were evaluated because of intrapartum sepsis risk factors. Of the mothers of preterm infants, by the time of delivery 3 of 8 had been documented as GBS positive, 2 of 8 had been documented GBS negative, and 3 of 8 remained unknown. Only 1 of 25 women received adequate IAP, but the isolate was resistant to the administered antibiotic (clindamycin). Antibiotic resistance was not a factor in any other case, and no dominant serovariant was identified among tested isolates. Procedural errors (lack of recognition of documented GBS colonization or failure to evaluate infants at risk for sepsis) were identified in 4 cases. The majority of the remaining cases of EOGBS occurred in infants whose mothers screened negative for GBS colonization. Even in the setting of a maternal GBS-screening program, efforts to evaluate and treat infants with intrapartum clinical risk factors for early-onset sepsis remain important. Until effective vaccines against GBS are available for clinical use, development and implementation of rapid and sensitive techniques for screening for GBS status and antibiotic susceptibility at presentation may help prevent additional cases of invasive GBS disease.
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Objective: To evaluate the relationship between the time elapsed from the administration of ampicillin prophylaxis to delivery and its efficacy in interrupting intrapartum transmission of group B streptococcus. Methods: During the 12-month study period, all women who came to the Virgen de las Nieves Hospital (Granada, Spain) for delivery were screened for group B streptococcus vaginal carriage by a pigment-detection culture-based procedure. Colonized women were treated with ampicillin (2 g intravenously), and the interval between ampicillin administration and delivery was recorded. Newborns from colonized mothers also were screened to detect group B streptococcus colonization. Results: During the study period, 4525 women were admitted to the hospital for delivery and screened for group B streptococcus vaginal colonization. Group B streptococcus was detected in 543 women (12%), of whom 454 gave birth vaginally to 454 liveborn infants. Intrapartum ampicillin was given to 201 of these 454 women (44%), and 10% of the newborns from mothers who received intrapartum ampicillin prophylaxis were colonized by group B streptococcus. The relationship between timing of ampicillin administration and rate of neonatal group B streptococcal transmission was as follows: less than 1 hour before delivery, 46%; 1-2 hours, 29%; 2-4 hours, 2.9%; and more than 4 hours, 1.2%. Among the 253 mothers who received no intrapartum prophylaxis, colonization was found in 120 of their newborns (47%). Conclusion: When the time between the start of ampicillin prophylaxis and delivery is at least 2 hours, vertical transmission of group B streptococcus is minimized. (C) 1998 The American College of Obstetricians and Gynecologists
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Most early-onset group B streptococcal (GBS) disease in recent years has occurred in newborns of prenatally GBS-negative mothers who missed intrapartum antibiotic prophylaxis (IAP). We aimed to assess the accuracy of prenatal culture in predicting GBS carriage during labor, the IAP use, and occurrence of early-onset GBS disease. We obtained vaginal-rectal swabs at labor for GBS culture from 5497 women of ≥ 32 weeks' gestation and surface cultures at birth from newborns between February 5, 2008 and February 4, 2009 at 3 hospitals in Houston, TX and Oakland, CA. Prenatal cultures were performed by a healthcare provider during routine care, and culture results were obtained from medical records. The accuracy of prenatal culture in predicting intrapartum GBS carriage was assessed by positive and negative predictive values. Mother-to-newborn transmission of GBS was assessed. Newborns were monitored for early-onset GBS disease. GBS carriage was 24.5% by prenatal and 18.8% by labor cultures. Comparing prenatal with labor GBS cultures of 4696 women, the positive predictive value was 50.5% and negative predictive value was 91.7%. IAP, administered to 93.3% of prenatally GBS-positive women, was 83.7% effective in preventing newborn's GBS colonization. Mother-to-newborn transmission of GBS occurred in 2.6% of elective cesarean deliveries. Two newborns developed early-onset GBS disease (0.36/1000 births); the prenatal GBS culture of one was negative, the other's was unknown. IAP was effective in interrupting mother-to-newborn transmission of GBS. However, approximately 10% of prenatally GBS-negative women were positive during labor and missed IAP, whereas approximately 50% of prenatally GBS-positive women were negative during labor and received IAP. These findings emphasize the need for rapid diagnostics during labor.
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Four different types of evaluation methods, cost-benefit analysis (CBA), cost-utility analysis (CUA), cost-effectiveness analysis (CEA) and cost-minimization analysis (CMA), are usually distinguished. In this note, we pronounce the (near) death of CMA by showing the rare circumstances under which CMA is an appropriate method of analysis. We argue that it is inappropriate for separate and sequential hypothesis tests on differences in effects and costs to determine whether incremental cost-effectiveness (or cost-utility) should be estimated. We further argue that the analytic focus should be on the estimation of the joint density of cost and effect differences, the quantification of uncertainty surrounding the incremental cost-effectiveness ratio and the presentation of such data as cost-effectiveness acceptability curves. Two examples from recently published CEA are employed to illustrate the issues. The first shows a situation where analysts might be tempted (inappropriately) to employ CMA rather than CEA. The second illustrates one of the rare circumstances in which CMA may be justified as a legitimate form of analysis. Copyright © 2001 John Wiley & Sons, Ltd.
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The objective of this study was to estimate the economic costs over the first 2 years of life of Group B Streptococcus (GBS) disease occurring in infants less than 90 days of age. A cost analysis was conducted using a prospective cohort of children born between 2000 and 2003 in the Greater London, Oxford, Portsmouth and Bristol areas of England. Unit costs were applied to estimates of the health and social resource use made by 138 infants diagnosed with GBS disease and 305 non-GBS controls matched for birth weight and hospital stay and time of birth. The health and social care costs for infants exposed to GBS disease were analysed in a multiple linear regression model. The mean health and social care cost over the first 2 years of life was estimated at pound11,968.9 for infants with GBS, compared to pound6,260.7 for the non-GBS controls; a mean cost difference of pound5,708.1 (bootstrap 95% CI pound2,977.1, pound8,391.2, P=0.03). After adjusting for gestational age and other potential confounders in a multiple linear regression, mean societal costs was pound6,144.7 higher among GBS cases than among non-GBS controls (P<0.001). This study shows that the health and social care costs for infants with GBS disease is, on average, two-fold higher during the first 2 years of life than for infants without GBS disease. These data should be used to inform policy decisions regarding the cost-effectiveness of prevention and treatment strategies for GBS disease during early childhood.
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Most cases of neonatal group B streptococcal disease with early onset have an intrapartum pathogenesis. Attack rates are increased substantially in infants born to mothers with prenatal group B streptococcal colonization and various perinatal risk factors (premature labor, prolonged membrane rupture, or intrapartum fever). In a randomized controlled trial, we studied the effect of selective intrapartum prophylaxis with ampicillin in 160 such high-risk women. In infants born to mothers who received intravenous ampicillin during labor, as compared with controls who received no treatment, neonatal colonization with group B streptococci was present in 8 of 85 (9 percent) versus 40 of 79 (51 percent; P less than 0.001), colonization at multiple (greater than or equal to 3) sites was observed in 3 of 85 (4 percent) versus 24 of 79 (30 percent; P less than 0.001), and bacteremia occurred in none of 85 versus 5 of 79 (6 percent; P = 0.024). The side effects of ampicillin were limited to a single episode of urticaria in a mother who had no history of penicillin allergy. We conclude that intrapartum ampicillin prophylaxis in women with positive prenatal cultures for group B streptococci who have certain perinatal risk factors can prevent early-onset neonatal group B streptococcal disease.
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Editor—Beardsall and colleagues are to be congratulated on presenting further evidence that group B streptococcus gives rise to a significant burden of disease in some areas of the United Kingdom.1 Retrospective data collected at St George's Hospital is in agreement with the authors' suggestion that culture proven sepsis under represents the true burden of disease. Firstly, we conducted a retrospective search for cases of culture positive group B streptococcus (either blood …
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To evaluate the costs and benefits of a group B streptococci screening strategy using a new, rapid polymerase chain reaction test in a hypothetical cohort of expectant mothers in the United States. Cost-benefit analysis using the human capital method. We developed a decision model to analyze the costs and benefits of a hypothetical group B streptococci screening strategy using a new, rapid polymerase chain reaction test as compared with the currently recommended group B streptococci screening guidelines-prenatal culture performed at 35 to 37 weeks or risk-factor-based strategy with subsequent intrapartum treatment of the expectant mothers with antibiotics to prevent early-onset group B streptococcal infections in their infants. A hypothetical cohort of pregnant women and their newborns. Screening strategies for group B streptococci using the new polymerase chain reaction technique, the 35- to 37-week culture, or maternal risk factors. Infant infections averted, infant deaths, infant disabilities, costs, and societal benefits of healthy infants. A screening strategy using the new polymerase chain reaction test generates a net benefit of $7 per birth when compared with the maternal risk-factor strategy. For every 1 million births, 80 700 more women would receive antibiotics, 884 fewer infants would become infected with early-onset group B streptococci, and 23 infants would be saved from death or disability. The polymerase chain reaction-based strategy generates a net benefit of $6 per birth when compared with the 35- to 37-week prenatal culture strategy and results in fewer maternal courses of antibiotics (64 080 per million births), fewer perinatal infections with early-onset group B streptococci (218/million), and a reduction in 6 infant deaths and severe infant disability per million births. The benefits hold over a wide range of assumptions regarding key factors in the analysis. Although additional clinical trials are needed to establish the accuracy of this new polymerase chain reaction test, initial studies suggest that strategies using this test will be superior to the other 2 strategies. Using the rapid polymerase chain reaction test becomes less attractive as the cost of the test increases. The test's greatest strengths lie in its ability to identify women and infants at risk at the time of labor, thereby decreasing the number of false-positives and false-negatives seen with the other 2 strategies and allowing for more accurate and effective intrapartum prophylaxis.
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Although increased use of intrapartum antibiotics caused significant declines in early-onset group B Streptococcus (GBS) infection, the effect on infections caused by other pathogens is not clear. The objective of this study was to determine trends in the incidence of early-onset sepsis caused by organisms other than group B streptococcus in the era of antimicrobial prophylaxis. We conducted surveillance for early-onset sepsis as part of the Active Bacterial Core surveillance. A case was defined as isolation of bacteria from blood or cerebrospinal fluid from an infant who was 0 to 6 days of age and born in the surveillance area during 1998 through 2000 (248 184 births). We identified 408 cases of early-onset infection. GBS caused 166 (40.7%) cases (52 in 1998, 51 in 1999, and 63 in 2000 for incidences 0.62, 0.62, and 0.76 cases per 1000 live births, respectively). Other bacterial pathogens were identified in 242 cases (82 in 1998, 79 in 1999, and 81 in 2000 for incidences 0.99, 0.95, and 0.98 per 1000 live births, respectively) of early-onset sepsis. Escherichia coli caused 70 cases (0.25, 0.28, and 0.31 cases per 1000 live births, respectively, in 1998-2000). The proportion of E coli infections that were resistant to ampicillin increased significantly among preterm infants from 29% (2 of 7) in 1998 to 84% (16 of 18) in 2000 but not in full-term infants: 50% (4 of 8) in 1998 and 25% (1 of 4) in 2000. Whereas rates of early-onset sepsis caused by GBS and other pathogens were low and did not change significantly during the study period, antibiotic-resistant E coli infections among preterm infants increased. Overall, these trends are reassuring, but careful evaluation of the increase in resistant infections in very young infants is critical in the future.
Article
Heavy colonization with group B streptococcus (GBS) has been associated with increased risk of preterm birth and neonatal sepsis; the burden of neonatal GBS disease varies geographically. To determine whether variation in heavy colonization and GBS serotypes could contribute to geographic differences in disease burden, we assessed the prevalence of heavy colonization and the distribution of serotypes in asymptomatic pregnant women in multiple countries. Cervical, lower vaginal and urine samples were collected from women attending seven prenatal clinics in six countries. Light colonization was defined as GBS isolation from Lim broth only; heavy colonization was isolation from urine or sheep blood agar plates. Isolates were serotyped using capillary precipitation. GBS was present in 11.3% of 1308 participants (range 7.1-21.7%); 5.0% were heavily colonized (0.4-18.8%) and 6.4% were lightly colonized (2.9-8.0%). Serotypes III and V were most common (both 17.2%). Serotypes VII and VIII were found in one study center. The prevalence of heavy colonization and GBS serotypes varied significantly among our study centers. Whether this variation could in part explain geographic differences in neonatal morbidity and mortality is a hypothesis that needs further study.
Article
Group B streptococcus (GBS) is the leading cause of neonatal sepsis and meningitis. Despite optimal treatment of GBS-infected neonates it is associated with significant morbidity and mortality, and prevention strategies are required. As disease occurs rapidly, and is often evident at birth or within 12 hours of birth, antibiotics must be given prior to delivery, and when administered early enough, and at the correct doses, they will prevent the majority of early-onset GBS cases. Prevention is therefore in the hands of obstetricians and midwives. Women at higher risk of delivering infected infants can be identified through one of two strategies: the presence of one or more clinical risk factors, or the presence of GBS on lower vaginal/rectal swabs obtained late in pregnancy. Decisions on which strategy to use will depend on a number of factors. A swab-based approach appears to have higher efficacy but is likely to lead to more antibiotic exposure.
The estimated incidence of true early-onset group B streptococcal (GBS) neonatal infection is based on positive GBS blood or cerebrospinal fluid (CSF) culture results, but the real burden of disease is underestimated owing to the high incidence of culture-negative sepsis possibly because of antibiotic administration to the mother. To examine the rate of probable early-onset GBS neonatal sepsis and to assess its impact on total GBS neonatal disease. A multicentre longitudinal prospective surveillance of 107,021 deliveries. The rates of culture-proven and probable early-onset GBS sepsis were 0.39 and 0.47 per 1000 live births, respectively. Of great concern was the finding of three deaths related to the infection in the group with probable early-onset GBS sepsis. The use of chemoprophylaxis in GBS-colonised pregnant women, especially when it is incomplete, may not be sufficient to prevent clinical neonatal infection, but may inhibit the growth of GBS in blood and CSF cultures. In assessing the effectiveness of GBS prophylaxis, it is advisable to consider the incidence of culture-positive and probable culture-negative GBS neonatal infection.
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