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ABSTRACT: BACKGROUND:: The 13-valent pneumococcal conjugate vaccine (PCV13) was introduced for routine administration to infants and children in 2010 in the United States. We have monitored clinical and microbiologic features of invasive pneumococcal infections among children before and after PCV13 use. METHODS:: Infants and children cared for at 8 children hospitals in the United States with culture-proven invasive infections caused by S. pneumoniae were identified in an ongoing prospective surveillance study. Demographic and clinical data were recorded on a standard case report form. Serotype and antimicrobial susceptibilities of isolates were determined. RESULTS:: Since routine PCV13 immunization in 2010, invasive pneumococcal infections decreased 42% overall and 53% for children <24 months of age in 2011 compared with the average number of cases for 2007 to 2009. PCV13 serotype isolates decreased 57% during these same time periods; 19A, 7F and 3 decreased by 58%, 54% and 68%, respectively. The number of infections caused by serotypes 1 and 6C also decreased in 2011. The most common non-PCV13 serotypes encountered in 2010 and 2011 combined were 33F, 22F, 12, 15B, 15C, 23A and 11. Bacteremia, pneumonia and mastoiditis cases decreased more than meningitis cases. CONCLUSIONS:: After the introduction of PCV13, invasive pneumococcal infections decreased among 8 children hospitals compared with the 3 years before PCV13 use. Slight increases in some non-PCV13 serotype isolates were noted in 2011. Continued surveillance is necessary to determine the effectiveness of PCV13 including herd protection as well as any emerging invasive serotypes.
The Pediatric Infectious Disease Journal 03/2013; 32(3):203-207. · 3.58 Impact Factor
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Kristina G Hulten,
Sheldon L Kaplan,
Linda B Lamberth, William J Barson,
José R Romero,
Philana Ling Lin,
John S Bradley,
Laurence B Givner,
Tina Q Tan,
Jill A Hoffman,
Edward O Mason
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ABSTRACT: Among 594 Streptococcus pneumoniae serotype 19A invasive pneumococcal disease (IPD) isolates from 1993-2011, we identified 85 sequence types (ST) by multilocus sequence typing (MLST). CC320 was associated with multidrug resistance and reduced susceptibility to penicillin and ceftriaxone and still predominated among declining serotype 19A IPD isolates following PCV13 introduction.
Journal of clinical microbiology 02/2013; · 4.16 Impact Factor
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Morgan C Green,
Edward O Mason,
Sheldon L Kaplan,
Linda B Lamberth,
Stephanie H Stovall,
Laurence B Givner,
John S Bradley,
Tina Q Tan, William J Barson,
Jill A Hoffman,
Philana Ling Lin,
Kristina G Hulten
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ABSTRACT: Streptococcus pneumoniae serotype 6C, which was described in 2007, causes invasive disease in adults and children. We investigated the prevalence of 6C among pediatric isolates obtained from eight children's hospitals in the United States. S. pneumoniae isolates were identified from a prospective multicenter study (1993 to 2009). Fifty-seven serotype 6C isolates were identified by multiplex PCR and/or Quellung reaction. Five were isolated before 2000, and the prevalence increased over time (P < 0.000001). The median patient age was 2.1 years (range, 0.2 to 22.5 years). Clinical presentations included bacteremia (n = 24), meningitis (n = 7), pneumonia (n = 4), abscess/wound (n = 3), mastoiditis (n = 2), cellulitis (n = 2), peritonitis (n = 1), septic arthritis (n = 1), otitis media (n = 10), and sinusitis (n = 3). By broth microdilution, 43/44 invasive serotype 6C isolates were susceptible to penicillin (median MIC, 0.015 μg/ml; range, 0.008 to 2 μg/ml); all were susceptible to ceftriaxone (median MIC, 0.015 μg/ml; range, 0.008 to 1 μg/ml). By disk diffusion, 16/44 invasive isolates (36%) were nonsusceptible to erythromycin, 19 isolates (43%) were nonsusceptible to trimethoprim-sulfamethoxazole (TMP-SMX), and all isolates were clindamycin susceptible. Multilocus sequence typing (MLST) revealed 24 sequence types (STs); 9 were new to the MLST database. The two main clonal clusters (CCs) were ST473 and single-locus variants (SLVs) (n = 13) and ST1292 and SLVs (n = 23). ST1292 and SLVs had decreased antibiotic susceptibility. Serotype 6C causes disease in children in the United States. Emerging CC1292 expressed TMP-SMX resistance and decreased susceptibility to penicillin and ceftriaxone. Continued surveillance is needed to monitor changes in serotype prevalence and possible emergence of antibiotic resistance in pediatric pneumococcal disease.
Journal of clinical microbiology 03/2011; 49(6):2097-101. · 4.16 Impact Factor
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ABSTRACT: The purpose of this study was to monitor the clinical and microbiologic features of invasive infections caused by Streptococcus pneumoniae among children before and after the introduction of the 7-valent pneumococcal conjugate vaccine (PCV7).
We conducted a 15-year prospective surveillance study of all invasive pneumococcal infections in children. The sample included infants and children at 8 children's hospitals in the United States with culture-proven invasive S pneumoniae infections.
Since the implementation of routine PCV7 immunization in 2000, invasive infections have decreased yearly from 2001 through 2004, to a nadir of 151 infections; the rate then increased from 2005 through 2008. Compared with the pre-PCV7 era, a greater proportion of children with invasive pneumococcal infection had an underlying condition in the post-PCV7 period. Compared with the total number of annual admissions, the number of 19A isolates increased significantly from 2001 to 2008 (P < .00001). In 2007 and 2008, only 16 isolates (4%) were vaccine serotypes; 19A accounted for 46% (168 of 369) of the non-PCV7 serotypes. Thirty percent of the 19A isolates were multidrug resistant. Serotypes 1, 3, and 7F accounted for 22% of the non-PCV7 serotypes. Among children with invasive pneumococcal infections, the likelihood of a 19A serotype increased with the number of preceding PCV7 doses.
Since 2005, the number of invasive pneumococcal infections in children has increased at 8 children's hospitals, primarily as a result of serotype 19A isolates, one third of which were resistant to multiple antibiotics in 2007 and 2008. Continued surveillance is necessary to detect emerging serotypes after the planned introduction of 13-valent or other pneumococcal vaccines.
PEDIATRICS 02/2010; 125(3):429-36. · 4.47 Impact Factor
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ABSTRACT: Introduction of the heptavalent conjugate vaccine for Streptococcus pneumoniae (PCV7) has led to a dramatic decline in meningitis by PCV7 serotypes, raising the possibility of similar trends by PCV7-related serogroups through cross-protection. A present concern, however, is of serotype replacement by pneumococci not related to PCV7 serogroups. If this occurs, there are currently few data to predict whether clinical outcomes will change substantially.
To address these questions, we analyzed medical records of 86 cases of pneumococcal meningitis treated at Nationwide Children's Hospital (1993-2004). Adverse neurologic sequelae and death were compared between cases with cerebrospinal fluid isolates characterized as vaccine-related serogroups-serotypes belonging to PCV7 or related to PCV7 serogroups, and those designated nonvaccine serogroups-serotypes neither belonging to PCV7 nor related to PCV7 serogroups. Serotype 19A, because of recent reports of increased incidence, was subanalyzed separately.
Thirty-six of 86 (42%) subjects had serious complications, including 6 who died. All 6 deaths occurred in patients with vaccine-related serogroups. Deafness was the most common complication, occurring in 26 (32.5%) survivors. There was no difference in the frequency of total complications between PCV7-related and non-PCV7 groups: 5 of 12 (42%) for non-PCV7 serogroups versus 31 of 74 (42%) for PCV-related serogroups (OR: 1.0; 95% CI: 0.2-4.0). Serious outcomes occurred in 3 of 4 cases due to serogroup 19A. Non-PCV7 serogroups increased slightly at the end of the study period.
In children with pneumococcal meningitis, infections with non-PCV7 serogroups seem less likely to result in death. Among survivors, there is preliminary evidence of parity in neurologic sequelae between PCV7 and non-PCV7 serogroups.
The Pediatric Infectious Disease Journal 10/2008; 27(9):771-5. · 3.58 Impact Factor
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ABSTRACT: Recurrent systemic pneumococcal infection usually occurs in immunocompromised patients and patients with underlying conditions.
Between 1993 and 2006, investigators at 8 pediatric hospitals prospectively identified cases of invasive pneumococcal disease (IPD) and retrospectively documented demographics and clinical information. Antibiotic susceptibility was determined for penicillin and ceftriaxone by microbroth dilution. Isolates were serotyped and molecular relatedness determined using pulse field gel electrophoresis (PFGE).
Four thousand sixty-seven children were diagnosed with IPD over 12.3 years. One hundred and 8 episodes of recurrent disease were seen in 90 children (2.6%); 75 experienced 2 infections, 12 experienced 3 infections and 3 experienced 4 infections. Fourteen of the 15 children with >2 episodes of infection had underlying conditions. The mean duration between 1st and 2nd infection was 22.9 weeks for children with no known underlying condition and 43.0 weeks for children with an underlying condition (P = 0.001). Seventy episodes of IPD among the 90 patients were caused by a different serotype or a different genotype as demonstrated by the PFGE. Sixteen children had intervals <30 days between infections; 7 were caused by different strains.
Approximately 80% of the children with recurrent invasive pneumococcal disease had underlying conditions. Seven of 16 children with recurrent infection <30 days apart were caused by acquisition of a new strain. Relapse of infection requires documentation that the pneumococcal isolates are not only the same serotype but also have the same PFGE patterns.
The Pediatric Infectious Disease Journal 06/2007; 26(6):480-4. · 3.58 Impact Factor
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Sheldon L Kaplan,
Gordon E Schutze,
John A D Leake, William J Barson,
Natasha B Halasa,
Carrie L Byington,
Charles R Woods,
Tina Q Tan,
Jill A Hoffman,
Ellen R Wald,
Kathryn M Edwards,
Edward O Mason
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ABSTRACT: Meningococcal disease continues to result in substantial morbidity and mortality in children, but there is limited recent surveillance information regarding serogroup distribution and outcome in children in the United States. The objective of this study was to collect demographic, clinical, laboratory, and outcome information for infants and children who had Neisseria meningitidis infections of various serogroups and were cared for in 10 pediatric hospitals.
Investigators at each of the participating hospitals identified children with meningococcal infections and collected demographic and clinical information using a standard data form. Meningococcal isolates were sent to a central laboratory for serogrouping by slide agglutination and penicillin susceptibility.
From January 1, 2001, through March 15, 2005, 159 episodes of systemic meningococcal infections were detected. The greatest numbers of children were younger than 12 months (n = 41) or were 12 to 24 months of age (n = 22). Meningitis was the most common clinical manifestation of disease accounting for 112 (70%) cases; 43 (27%) children had bacteremia only. Children who were younger than 5 years (17 of 102) were significantly less likely to require mechanical ventilation than children who were 5 to 10 years of age (12 of 24) or children who were older than 10 years (13 of 33). Overall, 55 (44%) isolates were serogroup B, 32 (26%) were serogroup C, and 27 (22%) were serogroup Y. All but 1 isolate (intermediate) were susceptible to penicillin. The overall mortality rate was 8% (13 of 159) but was greater for children who were > or = 11 years of age (7 [21.2%] of 33) than for children who were younger than 11 years (6 [4.8%] of 126). Unilateral or bilateral hearing loss occurred in 14 (12.5%) of 112 children with meningitis.
The morbidity and the mortality of meningococcal infections are substantial. With the recent licensure of meningococcal conjugate vaccines, our baseline trends in meningococcal disease can be compared with those seen after widespread vaccination to assess the success of routine immunization.
PEDIATRICS 10/2006; 118(4):e979-84. · 4.47 Impact Factor
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The Pediatric Infectious Disease Journal 05/2005; 24(4):387. · 3.58 Impact Factor
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ABSTRACT: Endocarditis due to Streptococcus pneumoniae is unusual in children, accounting for 3%-7% of all cases of childhood endocarditis. The US Pediatric Multicenter Pneumococcal Surveillance Group has prospectively identified patients with invasive disease at 8 children's hospitals. During the period of 1 September 1993 through 28 February 2003, a total of 11 children with pneumococcal endocarditis were seen. Seven (64%) were 3-36 months old; 8 (73%) were boys. Ten (91%) had preexisting structural heart disease; 5 had undergone previous heart surgery. Concomitant sites of infection were noted in 6 patients (55%), including 3 patients with meningitis. One patient (9%) died during hospitalization, and 5 others (45%) experienced serious complications. Only 2 patients remained hospitalized for their entire course of parenteral antibiotic therapy. Eight of 10 pneumococcal isolates tested were vaccine or vaccine-related serotypes included in the currently licensed 7-valent conjugated pneumococcal vaccine. Pneumococcal endocarditis in children is unusual but often has serious complications.
Clinical Infectious Diseases 06/2004; 38(9):1273-8. · 9.15 Impact Factor
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ABSTRACT: To monitor clinical and microbiologic features including antimicrobial susceptibility and serogroup distribution of invasive infections caused by Streptococcus pneumoniae among children before and after the introduction of routine administration of the 7-valent pneumococcal conjugate vaccine (PCV7).
A 9-year (January 1, 1994 through December 31, 2002) prospective surveillance study of all invasive pneumococcal infections in children.
Infants and children cared for at 8 children's hospitals in the United States with culture-proven invasive infections caused by S pneumoniae.
When compared with the mean of the years 1994 to 2000, the annual number of invasive pneumococcal infections for children < or =24 months of age declined 58% in 2001 and 66% in 2002. If only the serogroups in the PCV7 are considered, the number of cases in children < or =24 months old declined 63% and 77% in 2001 and 2002, respectively. The greatest decrease was observed for serogroup-14 isolates. The number of isolates in nonvaccine serogroups increased 28% in 2001 and 66% in 2002 for children < or =24 months old. Nonvaccine serogroup-15 and -33 isolates had the greatest increase in number. The proportion of all isolates nonsusceptible to penicillin increased yearly from 1994 to 2000, reached a plateau in 2001 at 45%, and declined to 33% in 2002. Decrease in nonsusceptibility to penicillin occurred entirely in the isolates with penicillin minimum inhibitory concentration > or =2 microg/mL. Nonsusceptibility to penicillin increased slightly among nonvaccine-serotype isolates. Most infections after at least 2 doses of PCV7 were caused by nonvaccine-serotype isolates.
Since the introduction of the PCV7, the number of invasive pneumococcal infections caused by vaccine-serogroup isolates among 8 US children's hospitals has decreased >75% among children < or =24 months old. In addition, penicillin resistance decreased in 2002 for the first time since our surveillance began in 1993-1994. However, we have noted that replacement may be developing with serogroups 15 and 33. Furthermore, penicillin resistance seems to be increasing among nonvaccine serogroups. Surveillance must be continued to detect the emergence of changes in the distribution of serotypes as well as antibiotic susceptibility.
PEDIATRICS 03/2004; 113(3 Pt 1):443-9. · 4.47 Impact Factor
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ABSTRACT: Streptococcus pneumoniae infections in the neonate (SPIN) are relatively unusual events (1%-11% of neonatal sepsis) but are associated with substantial morbidity and mortality. Previous reports suggest that invasive SPIN is associated with prolonged rupture of membranes, maternal colonization/illness, prematurity, early-onset pneumonia presentation (<72 hours), and high mortality (50%). The aim of this study was to review the current epidemiology and clinical course of SPIN.
The US Pediatric Multicenter Pneumococcal Surveillance Group has been prospectively monitoring S pneumoniae infections since 1993 in 8 children's hospitals. For this report, data were gathered retrospectively from the charts of neonates who were 30 days of age and younger and had SPIN from September 1993 to February 2001. All pneumococcal isolates were sent to a central laboratory for serogrouping/typing and susceptibility testing.
Twenty-nine cases of SPIN were identified from a total of 4428 episodes of S pneumoniae infection in children. Sixty-six percent were male, and 55% were white; the mean age was 18.1 day (+/-8.2). Ninety percent of infants were >or=38 weeks' gestation. Two mothers had bacterial infections at delivery; 1 had S pneumoniae isolated from both blood and cervix, and 1 had clinical amnionitis. The primary diagnoses in the neonates were bacteremia (8), meningitis (8), bacteremic pneumonia (4), septic arthritis/osteomyelitis (1), and otitis media (8). Thirty percent of infants with invasive SPIN presented with leukopenia/neutropenia, but this did not predict poor outcome. The infecting pneumococcal serogroups were 19 (32%); 9 (18%); 3 and 18 (11% each); 1, 6, and 14 (7% each); and 5 and 12 (3.5% each). Twenty-six percent of invasive neonatal infections were caused by serogroups 1, 3, 5, and 12, which are not contained in the heptavalent pneumococcal vaccine. In contrast, 6% of invasive nonneonatal disease was caused by these same nonvaccine serogroups. Susceptibility testing demonstrated that 21.4% of isolates were penicillin nonsusceptible and 3.6% were ceftriaxone nonsusceptible. Three (14.3%) neonates with invasive SPIN died; all deaths occurred within 36 hours of presentation. Deaths did not appear to be related to pneumococcal serogroup or susceptibilities.
Compared with previous studies of neonates with pneumococcal infection, this series showed that infants with SPIN were usually 2 to 3 weeks of age at presentation; likely to be full term; and ill with pneumonia, meningitis, and otitis media. This late-onset presentation was associated with an overall mortality rate of 10.3% (14.3% for invasive disease).
PEDIATRICS 12/2003; 112(5):1095-102. · 4.47 Impact Factor
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ABSTRACT: Increasing macrolide resistance among middle ear isolates complicates treatment of otitis media in children. When macrolide resistance is mediated via an efflux pump (M phenotype), the MICs of erythromycin, clarithromycin and azithromycin are usually below 32 microg/ml, and the pneumococcus remains susceptible to clindamycin. The association of prior specific macrolide therapy with the isolation of a macrolide resistant strain has not been reported.
To determine the mechanism of macrolide resistance in Streptococcus pneumoniae recovered from the middle ears of children with otitis media and their association, if any, with ethnicity, age, serogroup/serotype and prior antibiotic therapy.
Middle ear isolates collected by members of the United States Pediatric Multicenter Pneumococcal Surveillance Group during a 6-year period from September 1994 through August 2000 were studied. Antibiotic susceptibility to penicillin and ceftriaxone was determined by microbroth dilution. Disc diffusion susceptibility to erythromycin and clindamycin was performed to categorize macrolide resistance mechanisms. The medical record was reviewed to determine demographics and history of previous antibiotic therapy. Isolates were serogrouped or serotyped by the capsular swelling method.
Of the 1088 isolates available for testing, 51% were nonsusceptible to penicillin and 37% were nonsusceptible to erythromycin. Erythromycin resistance increased form 15% in 1994 through 1995 to 56% in 1999 through 2000. Seventy-five percent of macrolide-resistant strains were M phenotype. Macrolide resistance was less likely in isolates recovered from African-Americans and more likely in isolates obtained from children <3 years of age and from isolates obtained at time of tympanostomy tube placement. Neither erythromycin, nor clarithromycin nor azithromycin prescribed in the 30 days before infection was more likely than another to be associated with increased macrolide resistance. However, any macrolide alone or in combination with another antimicrobial taken before infection was associated with increased macrolide resistance among the S. pneumoniae organisms isolated from the middle ear.
Macrolide resistance among middle ear isolates of S. pneumoniae increased during the 6-year study. The proportion of M phenotype remained constant at 75%, meaning that these isolates remain susceptible to clindamycin. Continued surveillance to document potential changes is essential.
The Pediatric Infectious Disease Journal 07/2003; 22(7):623-7. · 3.58 Impact Factor
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ABSTRACT: Pneumococcal resistance to antimicrobials presents problems to physicians for empirical treatment of acute otitis media (AOM). Three hundred thirty-three isolates of Streptococcus pneumoniae selected for nonsusceptibility to penicillin (MIC >0.1 microg/ml) from the middle ear (n = 325) or mastoid (n = 8) of children seen between 1994 and 2000 at four children's hospitals in the United States were tested by broth microdilution for susceptibility to nine antibiotics. Using NCCLS 2002 breakpoints, resistance to the following drugs was as indicated: amoxicillin, 1%; azithromycin, 71%; cefprozil, 71%; ceftriaxone, 2%; cefdinir, 98%; erythromycin, 70%; levofloxacin, 0%; and trimethoprim-sulfamethoxazole, 93%. Of the penicillin- and erythromycin-nonsusceptible isolates, 97% were inhibited by cethromycin (ABT-773) and 83% were inhibited by telithromycin at a concentration of <or=0.125 microg/ml. Macrolide resistance among penicillin-nonsusceptible pneumococci increased from 44 to 80% in the 6 years of the study from which the isolates were selected; however, the proportion of isolates with M or MLS(B) phenotypes remained constant over the time period (53 and 18%, respectively). Prior treatment with a macrolide or clindamycin alone or in combination with a beta-lactam resulted in 94 or 85% of isolates causing infections being macrolide and or clindamycin resistant. No prior individual macrolide (azithromycin, erythromycin, or clarithromycin) resulted in more macrolide resistance or in a more prevalent resistance phenotype. The ketolides appear to be active antimicrobials against penicillin- and macrolide-resistant pneumococci.
Antimicrobial Agents and Chemotherapy 01/2003; 47(1):166-9. · 4.84 Impact Factor
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ABSTRACT: The frequency of children who are hospitalized with pneumococcal pneumonia complicated by necrosis, empyema/complicated parapneumonic effusion, and lung abscess seems to be increasing. The factors that contribute to this increase are unclear; therefore, the objective of this study was to describe and compare the relative frequency, clinical characteristics, and outcome of hospitalized children with complicated pneumonia with those of children with uncomplicated pneumonia caused by Streptococcus pneumoniae in the era of antibiotic resistance.
A multicenter, retrospective study of 8 children's hospitals in the United States was undertaken. A total of 368 children who were hospitalized with pneumococcal pneumonia identified from patients enrolled in the US Pediatric Multicenter Pneumococcal Surveillance Study over the period from September 1, 1993, to January 31, 2000 were studied. Demographic and clinical variables, antibiotic susceptibility, pneumococcal serotypes, antimicrobial therapy, and clinical outcome in hospitalized children with complicated versus uncomplicated pneumococcal pneumonia were measured.
A total of 368 patients with pneumococcal pneumonia were identified. Of the 368 isolates, 47 (12.8%) were intermediate and 37 (10.1%) were resistant to penicillin; 18 (5%) were intermediate to ceftriaxone, and 9 (2.5%) were resistant to ceftriaxone. A total of 133 patients met the criteria for complicated pneumonia and had a chest tube placed; 56 of these patients subsequently underwent decortication. The proportion of hospitalized patients with complicated pneumococcal pneumonia increased progressively over the study period from 22.6% in 1994 to 53% in 1999. Patients with complicated disease were older (median age: 45 vs 27 months) and significantly more likely to be of white race and have chest pain on presentation compared with patients with uncomplicated disease. Patients who had complicated disease and underwent decortication were more likely to have pleural fluid lactate dehydrogenase levels of >7500 IU/L compared with those patients who had chest tube placement alone. Fifty-three percent of children who were > or =61 months of age and were hospitalized had complicated pneumonia. This group of children accounted overall for 42% of the patients with complicated pneumonia, 48.2% of the patients who subsequently underwent decortication, and 44% of the patients who had received a course of antibiotics before diagnosis. Pneumococcal serotypes 1, 6, 14, and 19 were the most prevalent serotypes causing disease, with serotype 1 causing 24.4% of the complicated cases versus 3.6% of the uncomplicated cases. Ninety-eight percent of the patients in both groups recovered from their pneumonia. Antibiotic resistance was not found to be more prevalent in those patients with complicated disease.
The relative frequency of complicated disease in hospitalized children with pneumococcal pneumonia is increasing. Patients with complicated pneumococcal disease were older and significantly more likely to be of white race compared with those patients with uncomplicated disease. Pneumococcal serotype 1 caused significantly more disease in patients with complicated versus uncomplicated pneumonia. Patients with complicated disease were not more likely to be infected with an antibiotic-resistant isolate.
PEDIATRICS 07/2002; 110(1 Pt 1):1-6. · 4.47 Impact Factor
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ABSTRACT: Asplenia is associated with an increased risk of infections caused by Streptococcus pneumoniae. Overwhelming infection can be fulminate and lead to a fatal outcome.
To review the epidemiology and clinical course of invasive S. pneumoniae infections in children with asplenia before the release of the conjugate pneumococcal vaccine.
Children with S. pneumoniae infections from eight children's hospitals in the US were identified prospectively from September, 1993, to August, 1999. Further demographic, medical and microbiologic information was gathered retrospectively from the charts of patients with asplenia.
Twenty-two asplenic patients with 26 episodes of invasive S. pneumoniae were identified. This represents 1% of the 2,581 episodes of invasive S. pneumoniae infections identified in our study. Twelve had congenital asplenia (CA), and 10 had undergone surgical splenectomy. Nine of the patients with CA had associated complex congenital heart disease. The median age at first infection was 12.5 months for CA patients as compared with 69 months in children with surgical splenectomy (P < 0.001). Seventy-five percent of those eligible had received the polysaccharide pneumococcal vaccine. The most common serotypes isolated were 6B (8), 23F (7), 18C (2) and 19A (2). Antimicrobial prophylaxis had been prescribed for 82% of the study cohort. Clinical presentations of the 26 episodes included fever (22), shock (7), petechiae or purpura (7), disseminated intravascular coagulation (5) and respiratory distress (5). Clinical illness included bacteremia alone (12), meningitis alone (8), bacteremia with otitis media-sinusitis (3), bacteremia with pneumonia (2) and meningitis with osteomyelitis (1). Five of the 6 patients who died had meningitis. Three of the survivors (19%) had significant morbidity, and all of them had meningitis. Two patients had 2 episodes each, and 1 patient had 3 episodes. All but 1 of the multiple episodes was with a different serotype. Forty-six percent of isolates were nonsusceptible to penicillin, and 19% were nonsusceptible to ceftriaxone. There was no association between antimicrobial resistance and mortality.
Invasive pneumococcal disease in patients with asplenia has a high mortality, especially in those with meningitis. Even though the new conjugate vaccine might increase protection, 19% of patients had disease caused by serotypes not included in the current heptavalent vaccine. Clinicians should continue to be aggressive in evaluating asplenic patients with unexplained fevers.
The Pediatric Infectious Disease Journal 04/2002; 21(4):278-82. · 3.58 Impact Factor
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ABSTRACT: Monitor clinical and microbiologic features including antimicrobial susceptibility of invasive pneumococcal infections among children.
A 6-year (September, 1993, through August, 1999) prospective surveillance study of all invasive pneumococcal infections in children.
Infants and children cared for at eight children's hospitals in the United States with culture-proved invasive pneumococcal infection.
During the 6-year period 2581 episodes of invasive pneumococcal infection occurred in 2498 children. Underlying conditions were present in 29% of the children. Of children without an underlying condition, 15% of the total infections occurred in those 25 to 60 months old. As the ages of the children advanced the proportion of cases classified as bacteremia declined, whereas the proportion classified as pneumonia increased. Also, as the ages of the children increased the proportion of isolates in serotypes/serogroups 1, 3 and 23 increased. whereas the proportion for serotype 14 diminished. During the 6 years of the study, there was a significant increase in the percentage of isolates intermediate or resistant to penicillin (P < 0.000001) or intermediate to ceftriaxone (P < 0.002). By the sixth year of the study, 37 and 11% of the isolates were nonsusceptible to penicillin or ceftriaxone, respectively. Antibiotic use in the 30 days before diagnosis of systemic pneumococcal infection occurred in 30 to 35% of the children for each of the 6 years. The overall case-fatality rate for children with systemic pneumococcal infection was 1.56%. Mortality was greatest in children >60 months old and in those with underlying conditions; mortality was not related to antibiotic susceptibility.
The percentage of pneumococcal isolates recovered from children with systemic infection which were intermediate for penicillin or ceftriaxone or resistant to penicillin increased steadily during the 6-year period. There was also a trend toward increasing rates of resistance to ceftriaxone. The age and serogroup/serotype distributions of our patients support the recommendations to consider administration of the seven valent pneumococcal conjugate vaccine for all children 24 to 59 months old, with special consideration for selected groups.
The Pediatric Infectious Disease Journal 03/2002; 21(2):141-7. · 3.58 Impact Factor
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ABSTRACT: Objective. To determine patterns of resistance for isolates of Streptococcus pneumoniae recovered from middle ear fluids of children from eight children's hospitals between September, 1994, and August, 1997.
Methods. Data were extracted retrospectively from the medical records of eight children's hospitals. A standardized data form was completed for each episode of pneumococcal infection. Systemic isolates (blood and pleural, synovial and spinal fluids) of S. pneumoniae were collected during the same period. All isolates of S. pneumoniae from each center were sent to a central laboratory. Susceptibility to penicillin and ceftriaxone was determined by microbroth dilution. Organisms were considered nonsusceptible to penicillin if the minimum inhibitory concentration was ≥ 0.1 μg/ml and nonsusceptible to ceftriaxone if the minimum inhibitory concentration was ≥ 1.0 μg/ml.
Results. S. pneumoniae was recovered from the middle ear fluids of 707 children from all centers during the study period. Thirty-nine (5.5%) were infections recorded at 4 centers which evaluated middle ear fluid only sporadically and were not included in this analysis. The remaining 668 infections reported by the 4 remaining participating hospitals reflect the experience of 608 children. There were 54% boys; 440 (73%) were Caucasian, 111 (18%) were African-American, 38 (6%) were Hispanic and for 19 (3%) the race was not recorded. The children ranged in age from 16 days to 13.8 years with a mean (±sd) of 26.0 (± 26.1) months. Children who received antibiotics in the 30 days before the middle ear isolate was recovered were more likely to harbor a resistant strain of S. pneumoniae than children who had not recently received an antibiotic (P < 0.001). Isolates recovered from children with spontaneous otorrhea were more likely to be susceptible to penicillin than isolates recovered during myringotomy, with or without the insertion of tympanostomy tubes (P < 0.01). There was wide variation in the susceptibility of middle ear isolates to penicillin and ceftriaxone according to geographic location; however, in every locale the middle ear isolates were less likely to be susceptible to penicillin and ceftriaxone than systemic isolates of S. pneumoniae.
Conclusion. The prevalence of penicillin-resistant and cephalosporin-resistant S. pneumoniae in middle ear isolates derived from children cared for at four different children's hospitals was quite variable. In some locations the prevalence of resistance is still increasing, whereas in other areas the rate of resistance was at a plateau during the period of surveillance. The prevalence of isolates of S. pneumoniae susceptible to penicillin and ceftriaxone was always less common among middle ear isolates than among systemic isolates. Previous antibiotic use remains the most predictive factor for the recovery of isolates resistant to penicillin and ceftriaxone.
The Pediatric Infectious Disease Journal 12/2000; 20(1):34-39. · 3.58 Impact Factor
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Pediatric Research 03/1999; · 2.70 Impact Factor