[show abstract][hide abstract] ABSTRACT: This study aims to investigate the prevalence of a novel cell wall-anchored protein gene, sasX, and to obtain information on the genetic basis for the pathogenic potential of the MRSA strains isolated from Chinese children. The molecular and virulence characteristics of the clinical strains were analyzed. Twenty-two sequence types (STs) were obtained, with six epidemic clones ST59, ST239, ST1, ST910, ST88, and ST338 accounting for 35.8, 22, 6.6, 6.6, 5.3, and 4.1% respectively. The expression levels of hla, psmα, and RNAIII were higher in ST59 than in other STs (p < 0.05). The sasX gene was detected in 26 (10.7%) MRSA isolates. ST239-MRSA-SCCmecIII-t037 (61.5%) was the predominant sasX-positive MRSA clone. The expressions of PSMα and RNAIII were higher in sasX-positive ST239 isolates than in sasX-negative ST239 ones (p < 0.01). Notably, the percentage of invasive infection in infections caused by sasX-positive ST239 MRSA was higher than that by sasX-negative ST239 MRSA (p = 0.008). This study indicated that ST59 was the predominant clone in the MRSA isolates obtained from Chinese children and might have stronger pathogenic potential. The prevalence of the sasX gene in the MRSA isolates from children was relatively low. Furthermore, the sasX gene might be related to the expressions of PSMα and RNAIII and infection invasiveness.
[show abstract][hide abstract] ABSTRACT: Detailed molecular analyses of Clonal Complex 59 (CC59) methicillin-resistant Staphylococcus aureus (MRSA) isolates from children in seven major cities across Mainland China were examined. A total of 110 CC59 isolates from invasive and non-invasive diseases were analyzed by multilocus sequence typing (MLST), Staphylococcus cassette chromosome mec (SCCmec) typing, staphylococcal protein A (spa) typing and pulsed-field gel electrophoresis (PFGE). Antibiotics susceptibilities, carriage of plasmids and 42 virulence genes and the expression of virulence factors were examined. ST59 (101/110, 91.8%) was the predominant sequence type (ST), while single locus variants (SLVs) belonging to ST338 (8/110, 7.3%) and ST375 (1/110, 0.9%) were obtained. Three SCCmec types were found, namely type III (2.7%), type IV (74.5%) and type V (22.7%). Seven spa types including t437, which accounted for 87.3%, were determined. Thirteen PFGE types were obtained. PFGE types A and B were the major types totally accounting for 81.8%. The dominant clone was ST59-t437-IVa (65.5%), followed by ST59-t437-V (14.5%). The positive rate of luks-PV and lukF-PV PVL encoding (pvl) gene was 55.5%. Plasmids were detected in 83.6% (92/110) of the strains. The plasmid size ranging from 23.4 kb to 50 kb was most prevalent which accounted for 83.7% (77/92). A significantly lower expression of hla was found in ST59-t437-IVa compared with ST59-t437-V. Among the 110 cases, 61.8% of the patients were less than 1 year old. A total of 90 cases (81.8%) were community-associated (CA) infections whereas 20 cases (18.2%) were hospital-associated (HA) infections. Out of the 110 patients, 36.4% (40/110) were diagnosed with invasive infectious diseases in which ST59-t437-IVa accounted for 67.5% (27/40). In brief, ST59-t437-IVa was proved as the dominant clone in CC59 MRSA strains. The carriage rate of pvl gene was high. CC59 MRSA could result in CA and HA infections. The majortiy of MRSA infection children were in young age.
PLoS ONE 01/2013; 8(8):e70602. · 3.73 Impact Factor
[show abstract][hide abstract] ABSTRACT: To provide guidance for clinical disease prevention and treatment, this study examined the epidemiology, antibiotic susceptibility, and serotype distribution of Streptococcus pneumoniae (S. pneumoniae) associated with invasive pneumococcal diseases (IPDs) among children less than 14 years of age in Shenzhen, China.
All the clinical strains were isolated from children less than 14 years old from January 2009 to August 2012. The serotypes and antibiotic resistance of strains of S. pneumoniae were determined using the capsular swelling method and the E-test.
A total of 89 strains were isolated and 87 isolates were included. The five prevailing serotypes were 19F (28.7%), 14 (16.1%), 23F (11.5%), 19A (9.2%) and 6B (6.9%). The most common sequence types (ST) were ST271 (21.8%), ST876 (18.4%), ST320 (8.0%) and ST81 (6.9%) which were mainly related to 19F, 14, 19A and 23F, respectively. The potential coverage by 7-, 10-, and 13-valent pneumococcal conjugate vaccine were 77.0%, 77.0%, and 89.7%, respectively. Among the 87 isolates investigated, 11.5% were resistant to penicillin, and for meningitis isolates, the resistance rate was 100%. Multi-drug resistance (MDR) was exhibited by 49 (56.3%) isolates. Eighty-four isolates were resistance to erythromycin, among which, 56 (66.7%) carried the ermB gene alone and 28 (33.3%) expressed both the ermB and mefA/E genes.
The potential coverage of PCV13 is higher than PCV7 and PCV10 because high rates of serotypes 19A and 6A in Shenzhen. The clinical treatment of IPD needs a higher drug concentration of antibiotics. Continued surveillance of the antimicrobial susceptibility and serotypes distribution of IPD isolates may be necessary.
PLoS ONE 01/2013; 8(6):e67507. · 3.73 Impact Factor
[show abstract][hide abstract] ABSTRACT: This study aimed to correlate the multidrug resistance (MDR) and sequence type (ST) clones of community-associated (CA) meticillin-resistant Staphylococcus aureus (MRSA) to identify the genes responsible for clindamycin and mupirocin resistance in S. aureus isolates from paediatric hospitals in mainland China. A total of 435 S. aureus isolates were collected. Compared with CA meticillin-susceptible S. aureus (MSSA), the resistance rates of CA-MRSA to ciprofloxacin, chloramphenicol, gentamicin and tetracycline were higher (19.0 vs 2.6 %, P<0.001; 14.7 vs 3.1 %, P<0.001; 14.7 vs 3.1 %, P<0.01; and 46.0 vs 13.3 %, P<0.001, respectively). Compared with hospital-associated (HA)-MRSA, the resistance rates of CA-MRSA to ciprofloxacin, gentamicin, rifampicin, tetracycline and trimethoprim-sulfamethoxazole were lower (19 vs 94.8 %, P<0.001; 14.7 vs 84.4 %, P<0.001; 5.5 vs 88.3 %, P<0.001; 46 vs 94.8 %, P<0.001; and 1.8 vs 9.1 %, P<0.01, respectively). The resistance rates of CA-MRSA, HA-MRSA and CA-MSSA to clindamycin (92.0, 77.9 and 64.1 %, respectively) and erythromycin (85.9, 77.9 and 63.1 %, respectively) were high. The MDR rates (resistance to three or more non-β-lactams) were 49.6, 100 and 14 % in the CA-MRSA, HA-MRSA and CA-MSSA isolates, respectively. Five of seven ST clones in the CA-MRSA isolates, namely ST59, ST338, ST45, ST910 and ST965, had MDR rates of >50 % (67.9, 87.5, 100, 50 and 83.3 %, respectively). The constitutive phenotype of macrolide-lincosamide-streptogramin B (MLS(B)) resistance (69 %) and the ermB gene (38.1 %) predominated among the MLS(B)-resistant CA S. aureus strains. The resistance rate to mupirocin was 2.3 % and plasmids carrying the mupA gene varied in size between 23 and 54.2 kb in six strains with high-level resistance as determined by Southern blot analysis. The present study showed that resistance to non-β-lactams, especially to clindamycin, is high in CA-MRSA isolates from Chinese children and that the profile of resistance is related to clonal type. This study revealed distinctive patterns of MLS(B)-resistant genes among CA S. aureus isolates.
Journal of Medical Microbiology 05/2012; 61(Pt 9):1240-7. · 2.30 Impact Factor
[show abstract][hide abstract] ABSTRACT: The aim of this study was to explore the epidemiological and molecular characteristics of Streptococcus pyogenes in children from different cities in mainland China who were diagnosed with scarlet fever, impetigo and pharyngitis, as well as to detect asymptomatic carriers, between 2005 and 2008, and to compare the results with isolates from rural Chinese children with acute glomerulonephritis in 2005 and in the 1990s. Susceptibility tests to determine MICs and analysis of the presence of erythromycin-resistant genes (mefA, ermB and ermA) and emm gene typing were performed on 466 S. pyogenes isolates from Beijing, Shanghai, Chongqing and Shenzhen. Superantigen genes (speA and speC) were examined by performing PCR on isolates with the most prevalent emm genotype. All isolates were sensitive to penicillin, cefradine and ofloxacin. The highest rate of resistance was against clarithromycin (98.1 %), followed by erythromycin (97.6 %), azithromycin and clindamycin (both 97.2 %), and tetracycline (94.0 %). Among the 466 isolates, 421 (90.3 %) harboured the ermB gene, 145 (31.1 %) were speA-positive and 273 (58.6 %) were speC-positive. The speA gene was common in emm1.0 (88.8 %) and emm6.5 (83.3 %) genotypes. The speC gene was frequently observed in emm4.0 (90.0 %), emm12.0 (69.6 %), emm18.0 (66.7 %), emm22.0 (75.9 %) and emm80.0 (80.0 %) genotypes. The most prevalent emm genotypes in mainland China in recent years were emm1.0 and emm12.0. All isolates remained sensitive to β-lactams and quinolone.
Journal of Medical Microbiology 03/2012; 61(Pt 7):975-83. · 2.30 Impact Factor
[show abstract][hide abstract] ABSTRACT: To determine the variation in the Panton-Valentine leukocidin (PVL) gene sequences and different PVL-encoding phages of Staphylococcus aureus strains collected from children in mainland China, fifty-eight strains with PVL collected from 2007 to 2009 were used. Their molecular characteristics were examined. Primers were designed to sequence the PVL genes. Six PVL-encoding phages (ϕPVL, ϕ108PVL, ϕSLT, ϕSa2MW, ϕSa2958, and ϕSa2USA) were identified by PCR. Eleven sequence types (ST) were detected with ST59 (39.7%, 23/58) the most frequent ST, followed by 910 (22.4%, 13/58), and 338 (12.1%, 7/58). Single nucleotide polymorphisms (SNP) were identified at 11 locations in the PVL genes. SNP (nucleotide 1396, A→G) and SNP (nucleotide 1546, A→G) were observed in >10 sequences. Four additional SNP were non-synonymous. Both SNP (nucleotide 16, C→A) and SNP (nucleotide 62, C→T) were present in the same ST59 strain. SNP (nucleotide 527, A→G) was present in five strains belonging to ST30, 121, 1, and 93. SNP (nucleotide 1436, A→C) was present in one ST30 strain. Fifteen strains belonging to ST910, ST217, and ST30 carried a PVL phage that had an icosahedral head morphology. Nine ST59 strains carried ϕ108PVL. Three ST88 strains carried a PVL phage that had an elongated head morphology. Twenty-seven strains, including 60.9% (14/23) of ST59 and all ST338 strains, had no detectable phage. In conclusion, sequence variation in PVL genes and PVL-encoding phages was generally related to the lineage. ST59 strains may indeed carry novel PVL phages.
Microbiology and Immunology 03/2012; 56(3):155-62. · 1.55 Impact Factor
[show abstract][hide abstract] ABSTRACT: Beta-Hemolytic group G streptococci cause a considerable invasive disease burden and sometimes disease outbreaks. Little is known about the critical epidemiologic parameter of genetic relatedness between isolates. We determined the emm types of 65 Streptococcus dysgalactiae subsp. equisimilis isolates. We formulated multilocus sequence typing (MLST) primers with 6 of the 7 loci corresponding to the Streptococcus pyogenes MLST scheme. We performed MLST with 69 S. dysgalactiae subsp. equisimilis isolates to represent each emm type identified. These strains were further analyzed by pulsed-field gel electrophoresis (PFGE) typing. Sixteen emm types were observed. Eighteen unique combinations of allelic profiles (sequence types [STs]) were obtained with 12 profiles each accounting for multiple isolates. Forty-one MLST STs were observed. Analysis of the PFGE patterns generated revealed 10 clones. Over 80% of the isolates were distributed in 3 large clones. Isolates within 16 redundantly represented S. dysgalactiae subsp. equisimilis emm types shared identical or nearly identical STs and subtypes of PFGE, demonstrating concordance between the emm type and genetic relatedness. It is conceivable that some particular characteristics in the genomes of these strains are responsible for their predominance in different regions.
[show abstract][hide abstract] ABSTRACT: This study aims to determine the resistance rates and determinants of fusidic acid among Staphylococcus aureus isolates collected from Chinese pediatric patients with skin and soft tissue infections (SSTIs). Between 2008 and 2009, a total of 186 clinical S. aureus isolates were collected from the pediatric patients with SSTIs, abscess (44.6%) was the most common SSTI in children 0-16 years old. Four clinical isolates (4/186, 2.2%) were resistant to fusidic acid. Two of these isolates were methicillin-resistant S. aureus (MRSA) that carry the fusC gene. The other two isolates were methicillin-sensitive S. aureus (MSSA) that carry the fusB gene. In the two fusB-positive clinical isolates, the fusB gene was located in a transposon-like element that has 99% identity with a pUB101 fragment from S. aureus. The four fusidic acid-resistant clinical isolates were ST1-MRSA-SCCmecV-t127, ST93-MRSA-SCCmecIII-t202, ST680-MSSA-t5415, and ST680-MSSA-t377. The fusidic acid resistance rate of S. aureus isolated from Chinese pediatric patients with SSTIs was low, and the genes fusB and fusC were the main resistance determinants. The transposon-like element that contains the fusB gene might participate in the transmission of fusidic acid resistance genes. This is the first report regarding the emergence of fusidic acid-resistant clinical S. aureus isolates in mainland China.
[show abstract][hide abstract] ABSTRACT: This study aimed to evaluate the distribution of superantigen gene profiles and the presence of exfoliative toxin genes in community-acquired meticillin-resistant Staphylococcus aureus (CA-MRSA) isolated from Chinese children, and simultaneously to assess virulence gene profiles and genetic background. Of the CA-MRSA isolates, 88.9 % (88/99) harboured toxin genes, with sek as the most frequent toxin gene (62.6 %), followed by seq (61.6 %), seb (60.6 %) and sea (35.4 %). The eta gene was detected only in one ST398-IVa-spa t034 strain. The sed and etd genes were not found in any of the isolates tested. A total of 38 virulence genotypes were observed, of which the genotype seb-sek-seq (27.3 %, 24/88) comprised the majority, followed by sea-seb-sek-seq (18.2 %, 16/88). The enterotoxin gene cluster including seg-sei-sem-sen-seo-seu predominated at a rate of 15.1 %. The relationship among toxin genotypes, toxin genes encoding profiles of mobile genetic elements and genetic background was analysed. Among 66 clonal complex (CC) 59 isolates, 87.9 % (58/66) were positive for toxin genes, and 75.8 % (50/66) harboured the toxin gene combination seb-sek-seq. Among seb-sek-seq-positive CC59 strains, 42.0 % (21/50) also carried the sea gene. CC59 corresponded exclusively to accessory gene regulator 1 (agr-1). The data presented here enhance our current knowledge on the virulence determinants of CA-MRSA.
Journal of Medical Microbiology 01/2011; 60(Pt 1):35-45. · 2.30 Impact Factor
[show abstract][hide abstract] ABSTRACT: Eighty group G streptococcal stains were collected from Chinese children. Susceptibility testing was done by a double-dilution and a disk diffusion method. PCR was used to test drug-resistant genes, and the χ(2) test and definite probability methods were used to test for statistically significant differences among the three groups. Thirty-four isolates (42.5%) showed resistance to erythromycin. There are differences between the resistance characteristics of group G streptococci from different regions of China.
Antimicrobial Agents and Chemotherapy 10/2010; 55(1):402-4. · 4.57 Impact Factor
[show abstract][hide abstract] ABSTRACT: To investigate changes in the antimicrobial susceptibility of Streptococcus pyogenes isolates over a 16-year period, 456 group A streptococci isolates were collected from Chinese pediatric patients among 1993 to 1994 and 2005 to 2008. Susceptibilities to antibiotics were performed using agar dilution methods. The macrolide resistance genes ermB, ermTR, mefA, and tetracycline-resistant gene tetM and the int and xis genes of Tn916 family were detected by polymerase chain reaction. All 456 strains were analyzed by emm typing. Selected strains representing each emm type were further characterized by pulsed-field gel electrophoresis. The resistance rates of erythromycin and clindamycin both significantly increased during the 2 sample periods (79.7% versus 94% for erythromycin and 75.4% versus 96.9% for clindamycin). Telithromycin resistance rate increased from 20.37% to 87.93%. Among the macrolide resistance strains, the rate of strains with the genes int, xis, tetM, and ermB increased with time (16.05% versus 86.91%, P < 0.05). The emm1 and emm12 isolates had high rates of ermB gene, which increased after 16 years (65.2% versus 86.23% for emm1 and 7.7% versus 91.8% for emm12). This study demonstrates the increase in macrolide resistance in S. pyogenes in Chinese children over a 16-year period. The phenomenon may be related not only with the shift in the emm types but also with the change of macrolide-resistant mechanisms. The change of Tn916 family among the isolates may be related with the increased resistance.
[show abstract][hide abstract] ABSTRACT: The aim of this study was to investigate the molecular characteristics of community-acquired, methicillin-resistant Staphylococcus aureus (CA-MRSA) isolates from Chinese children. Ninety-nine isolates were collected from eight hospitals, and analyzed by multilocus sequence typing, staphylococcal chromosomal cassette mec (SCCmec) type, and spa typing. The Panton-Valentine leukocidin (PVL) gene was also detected. Overall, 14 sequence types (STs) were obtained, and ST59 (58.6%) was found to be the most prevalent, followed by ST1 (8%) and ST338 (8%). We also first registered the new ST1409. SCCmec type IV was the most predominant type at 67.7%, followed by SCCmec type V at 32.3%. SCCmec subtypes IVa, IVc, and IVg were found among the SCCmec type IV strains. Twenty-one spa types were also identified. Four new spa types were found by synchronization with the Ridom SpaServer and referring to the website (http://www.SeqNet.org). ST59-MRSA-IVa with t437 accounted for 40.4% of occurrences, making it the most prevalent clone. The prevalence of PVL genes was 58.6%, and multidrug resistance was observed in 95% of all isolates. This result indicates that CA-MRSA isolates in Chinese children are largely associated with the ST59-MRSA-IV clone, and that the predominant clones of CA-MRSA are spread all over the country.
[show abstract][hide abstract] ABSTRACT: Community-acquired, methicillin-resistant Staphylococcus aureus (CA-MRSA) has been associated with morbidity and mortality in various countries. In this study, we characterized the molecular and clinical features of pediatric CA-MRSA pneumonia in China. Between June 2006 and February 2008, 55 previously healthy children confined in eight hospitals countrywide were found to be afflicted with CA-MRSA pneumonia. A total of 55 strains collected from these children were analyzed by multilocus sequence typing (MLST), Staphylococcus cassette chromosome mec (SCCmec) typing, and spa typing. The Panton-Valentine leukocidin (PVL) gene was also detected. Overall, nine STs were obtained, with ST59 (40.4%) established to be the most prevalent type. We first registered the new ST1409 from a child with necrotizing pneumonia. SCCmecIVa was the most predominant type, followed by SCCmec type V. Twelve spa types were identified, of which one new spa type, t5348, was first detected and registered. One typical livestock-associated spa type, t034, was found in a 4-month-old girl living in the countryside. We also found that 40% of those isolates were PVL-positive. In addition, the median age of the children in this study was 10 months. A total of 69% (38/55) of the children with community-acquired pneumonia (CAP) had preceding influenza or influenza-like illness, and three ST910-MRSA-IV strains (PVL gene-positive) were associated with severe necrosis. The results indicated that the recent CA-MRSA found in Chinese children with CAP was largely associated with the spread of the ST59-MRSA-IV clone, and most of the PVL-positive strains in this study did not cause necrotic cases.
[show abstract][hide abstract] ABSTRACT: To evaluate the epidemiology and molecular features of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) and methicillin-sensitive S. aureus (MSSA) from children with skin and soft tissue infections (SSTIs) in Beijing, China, prospective community-acquired S. aureus SSTIs surveillance was conducted at the Beijing Children's Hospital, Beijing, China, for a 12-month period from August 1, 2008, to July 30, 2009. Susceptibility to 12 antimicrobials was determined by the agar dilution method. Genotypic characteristics of CA-MRSA isolates were tested by SCCmec typing, spa typing, and multilocus sequence typing. Panton-Valentine leukocidin gene was detected. Of 1104 cases, 31.8% (351) were community-acquired S. aureus. CA-MRSA accounted for 4% (14) of S. aureus. Among 14 CA-MRSA and 120 MSSA isolates tested, 100% and 91.7% were multidrug resistant, respectively. ST59-MRSA-IVa-t437 (42.9%) was the most common form of CA-MRSA. Spa typing analysis of 120 MSSA isolates was performed, followed by pulsed-field gel electrophoresis and multilocus sequence typing of a selected number of isolates. The most common spa types among MSSA were t084 (8.3%), t091 (5.8%), t034 (5%), t127 (4.2%), t002 (4.2%), and t796 (4.2%). No predominant spa type was seen. Of the MSSA isolates that could be classified into spa-CCs, 15.0% had a genetic background observed in CA-MRSA clones (spa-CC437, spa-CC342, and spa-CC377). Panton-Valentine Leukocidin (PVL)-positive community-acquired S. aureus strains were more commonly associated with skin abscesses than other SSTIs (29.4% versus 5.9%, P < 0.01).In conclusion, CA-MRSA infections are not common among Chinese children with SSTIs. Our findings show that MSSA strains in China have diverse genetic backgrounds.
[show abstract][hide abstract] ABSTRACT: A total of 171 Streptococcus pneumoniae isolates causing invasive disease were isolated from Chinese children. The serotype distribution and antimicrobial resistance were tested. The results suggested that the 7-valent pneumococcal conjugate vaccine has a preventive effect among children and that there should be long-term surveillance for serotype 19A.
[show abstract][hide abstract] ABSTRACT: Streptococcus pyogenes are highly prevalent bacterial pathogens, especially in school-aged children. However, the characteristics of asymptomatic carriers vary geographically in different countries. We aimed to investigate S. pyogenes isolated from healthy schoolchildren in China. From 2007 to 2008, a total of 94 S. pyogenes isolates were obtained from healthy schoolchildren in Beijing and Chongqing, China. Antimicrobial susceptibility testing, determination of macrolide resistance genes (ermB, ermA and mefA), emm genotyping, pulsed-field gel electrophoresis (PFGE), and multilocus sequence typing (MLST) were performed. The resistance rate to macrolides was 96.8% and to tetracycline was 92.6%. All macrolide-resistant isolates exhibited constitutive resistance; 77 isolates (84.6%) had the ermB gene, while 14 isolates (15.4%) had the ermA gene. Among the macrolide-resistant isolates, the most frequent emm type was emm12 (51.6%), followed by emm22 (14.3%) and ST1815 (8.8%). PFGE analysis revealed 12 different patterns, with a given pattern having the same sequence type (ST) by MLST and the same emm type. In conclusion, the rate of macrolide resistance to S. pyogenes is currently very high in China. This is due primarily to the dissemination of a limited number of clones.
[show abstract][hide abstract] ABSTRACT: This study surveyed the pattern of inpatient antibiotic use in five Chinese children's hospitals between 2002 and 2006, focusing on the antibiotics accounting for 90% of the volume utilised as well as the level of adherence to guidelines. The Anatomical Therapeutical Chemical Classification/Defined Daily Doses (ATC/DDD) and the drug utilisation 90% (DU90%) methodologies were used. In October 2004, national antibiotic guidelines were issued that divided antibiotics into non-restricted, restricted and special use grades. In five children's hospitals, a total of 56 different systemic antibiotics were used during the study period. Antibiotics that could be injected accounted for 59.0-99.8%. beta-Lactam antibacterials (ATC codes J01C and J01D) were the most used subgroups. The numbers of antimicrobial agents and non-restricted antibiotics within the DU90% segment were 11-20 and 5-9, respectively. The proportion of non-restricted antibiotic consumption was ca. 40% in 2006 in four hospitals, which varied among hospitals during the period 2002-2005. There was considerable variation both in the pattern and amount of antibiotics used in the five hospitals, with amoxicillin/clavulanic acid, cefuroxime and cefazolin being the most commonly used substances. We also observed a decrease in the ranks of some restricted and special use antibiotics after the guidelines were issued in one hospital. The DU90% profiles were proven to be useful in studying the pattern of antibiotic use in hospitals. Finally, the study observed the effectiveness of guidelines for antibiotic use in some hospitals, although injectable antibiotics were widely used in children's hospitals in China.
International Journal of Antimicrobial Agents 08/2008; 32(3):250-5. · 4.42 Impact Factor
[show abstract][hide abstract] ABSTRACT: To investigate the nasopharyngeal carriage and antimicrobial susceptibility of H. influenzae among children younger than 5 years old and to assess antibiotics usage patterns in the outpatient department of Beijing Children's Hospital from 2000 to 2004.
From 2000 to 2004, At least 100 strains of H. influenzae were isolated from the pediatric patients who were younger than 5 years and who presented with symptoms of acute upper respiratory tract infections during February to May in each of the study years. Antimicrobial susceptibilities were determined; and antibiotics usage was expressed as defined daily dose (DDD)/100 patient days.
The overall nasopharyngeal carriage rate of H. influenzae is 26.3% (562/2,137) in children younger than 5 years old with acute upper respiratory tract infection. The percentage of ampicillin-resistant isolates ranges from 4.0% (4/100) to 14.3% (17/119) from 2000 to 2004. All the ampicillin-resistant isolates are beta-lactamase producers. More than 80% of the isolates are susceptible to amoxicillin, cefaclor, and chloramphenicol; whereas, almost all (99-100%) of the isolates are sensitive to amoxicillin/clavulanic acid, ceftriaxone, and cefuroxime. For antibiotics utilization, macrolides are the predominantly used antibiotics, followed by cephalosporins and penicillins among pediatric patients in the outpatient department during the study period.
All amoxicillin-resistant isolates of H. influenzae are producing beta-Lactamase; and the rates of amoxicillin-resistant isolates are increasing over time. Amoxicillin/clavulanic acid and cephalosporins are highly sensitive to H. influenzae isolated from Chinese pediatric patients. Macrolides are the most used antibiotics in the outpatient department during the study period.
[show abstract][hide abstract] ABSTRACT: To demonstrate the effectiveness of an intervention in antibiotics prescribing, and evaluate the use of antibiotics in the pediatric intensive care unit (PICU) at the Beijing Children's Hospital.
Our interventions included (1) educating the pediatricians on antibiotics prescribing, (2) applying an antimicrobial spectrum chart, and (3) controlling the prescription of specific antibiotics with the use of a guideline. Nine hundred clinical records, including clinical information and antibiotic usage data, were selected retrospectatively from the PICU admissions during the pre- and post-intervention periods.
In this 5-year survey, the mean rate of antibiotic prescribing was greater than 95% in the PICU. More than 76% of the prescriptions were started empirically. The most frequently used antibiotics were third-generation cephalosporins. After the intervention, we found a reduction in the rate of antibiotic cost/patient/day (P < 0.05); a decrease in the prescription rate of third-generation cephalosporins and macrolides (P < 0.01); an increase in the prescription rate of beta-lactam/beta-lactamase inhibitors and second-generation cephalosporins (P < 0.01); a reduction in the empiric treatment (P < 0.01); and a significant reduction in the incidence rates of bacterial resistance for imipenem-, cefepime-, and ceftazidime-resistant Pseudomonas aeruginosa (P < 0.05), and cefepime-resistant Escherichia coli and Klebsiella pneumoniae (P < 0.01).
Our interventions led to a significant reduction of broad-spectrum antibiotic prescribing associated with the significant reduction in bacterial resistance in the PICU. The implementation of the antibiotics guideline appeared to be effective.
International Journal of Clinical Pharmacy 05/2008; 30(6):787-93. · 1.27 Impact Factor