Résumé
<p><b>OBJECTIVE</b>To characterize carbapenem (CPM)-non-susceptible Klebsiella pneumoniae (K. pneumoniae) and carbape-nemase produced by these strains isolated from Beijing Children's Hospital based on a five-year surveillance.</p><p><b>METHODS</b>The Minimal Inhibition Concentration values for 15 antibiotics were assessed using the Phonix100 compact system. PCR amplification and DNA sequencing were used to detect genes encoding carbapenemases. WHONET 5.6 was finally used for resistance analysis.</p><p><b>RESULTS</b>In total, 179 strains of CPM-non-susceptible K. pneumoniae were isolated from January, 2010 to December, 2014. The rates of non-susceptible to imipenem and meropenem were 95.0% and 95.6%, respectively. In the 179 strains, 95 (53.1%) strains carried the blaIMP gene, and IMP-4 and IMP-8 were detected in 92 (96.8%) and 3 (3.2%) IMP-producing isolates, respectively. 65 (36.3%) strains carried the blaNDM-1 gene. 6 (3.4%) strains carried the blaKPC gene, and KPC-2 were detected in 6 KPC-producing isolates. In addition, New Delhi-Metallo-1 (NDM-1) producing isolates increased from 7.1% to 63.0% in five years and IMP-4 producing isolates decreased from 75.0% to 28.3%.</p><p><b>CONCLUSION</b>High frequencies of multiple resistances to antibiotics were observed in the CPM-non-susceptible K. pneumoniae strains isolated from Beijing Children's Hospital. The production of IMP-4 and NDM-1 metallo-β-lactamases appears to be an important mechanism for CPM-non- susceptible in K. pneumoniae.</p>
Sujets)
Enfant , Humains , Antibactériens , Pharmacologie , Protéines bactériennes , Génétique , Métabolisme , Chine , Épidémiologie , Résistance aux substances , Régulation de l'expression des gènes bactériens , Physiologie , Régulation de l'expression des gènes codant pour des enzymes , Physiologie , Hôpitaux pédiatriques , Infections à Klebsiella , Épidémiologie , Microbiologie , Klebsiella pneumoniae , Génétique , Tests de sensibilité microbienne , Surveillance de la population , Facteurs temps , bêta-Lactamases , Génétique , MétabolismeRésumé
<p><b>OBJECTIVE</b>To investigate the prevalence and drug resistant patterns of community-acquired Methicillin-resistant Staphylococcus aureus (MRSA) in children.</p><p><b>METHODS</b>Samples of sputum, blood, liquor puris/secretion of skin or stool in Beijing Children's Hospital between January, 2002 and March, 2005 were cultured. The characteristics of community-acquired MRSA infection were analyzed and compared with hospital-acquired MRSA infection.</p><p><b>RESULTS</b>A total of 25 strains of MRSA were found during the study period and they accounted for 4.7% in 512 strains of Staphylococcus aureus. Of the 25 strains of MRSA, 20 strains were community-acquired but only 5 were hospital-acquired. The prevalence of MRSA infection in Staphyloccus aureus has kept rising over last two years, 3.1% in 2003, 5.4% in 2004 and 7.2% in the first season of 2005. There were no statistical differences in the results of antimicrobial susceptibility testing and multi-resistance testing between the groups of community-acquired and hospital-acquired MRSA. In both groups, all isolates were susceptible to vancomycin. The percentage of the patients with underlying disease in the hospital-acquired infection group was significantly higher than in community-acquired infection group (P < 0.05), but the onset age was not different.</p><p><b>CONCLUSIONS</b>The prevalence of community-acquired MRSA infection tends to increase in children. The drug resistant patterns of community-acquired MRSA were not significantly different from the hospital-acquired MRSA in children.</p>
Sujets)
Enfant , Enfant d'âge préscolaire , Humains , Nourrisson , Nouveau-né , Infections communautaires , Traitement médicamenteux , Microbiologie , Résistance à la méticilline , Infections à staphylocoques , Traitement médicamenteux , Microbiologie , Staphylococcus aureusRésumé
Objective To investigate the genotype of metallo-?-lactamases (MBL) produced by carbapenem resistant Pseudomonas aeruginosa in pediatric patients.Methods 59 strains of resistance to imipenem or meropenem were collected from December 2003 to November 2005 in Beijing children's hospital.Isolates were further evaluated for MBL production by two screening methods.MBL Etest strips were used to screen the phenotype of MBL production.Molecular screening for blaVIM,blaIMP,blaSPM and blaGIM was carried out using primers targeting the conserved regions of the MBL genes.The PCR fragments obtained with integron primers were sequenced on both strands.The nucleotide sequences were compared with sequences available over the Internet.Results Of the 59 carbapenem resistant Pseudomonas aeruginosa included in this study,29 (49.2%)were MBL positive using Etest methods,and 39 (66.1%) of these tested positive for MBL genes by PCR.35 (89.7%) were positive for blaIMP genes and 4 (10.3%) were positive for blaVIM genes.All isolates were negative for SPM and GIM DNA sequencing revealed that the IMP-1 was detected in 35 IMP-producing isolates,and VIM-2 was detected in 4 VIM-producing isolates.Conclusions This study has demonstrated that MBL-producing strains in pediatric are more common than in adult.IMP-1-producing strains are the main in pediatric,and VIM-2-producing strains concurred.The production of MBL is one of the important reasons of carbapenem resistant Pseudomonas aeruginosa in pediatric.It is very important to monitor the production of MBL.