Clinical characteristics and antimicrobial resistance of the bloodstream infections due to NDM-1 producing Klebsiella pneumoniae in children / 中国感染与化疗杂志

ABSTRACT

Objective To investigate the clinical characteristics and antibiotic resistance of the bloodstream infections due to NDM-1 producing Klebsiella pneumoniae in children.Methods The nonduplicate carbapenem-resistant Klebsiella pneumoniae (CRKp) strains isolated from blood samples were collected in Beijing Children's Hospital from January 2011 to August 2014.Antimicrobial susceptibility was tested with broth microdilution method.PCR amplification and DNA sequencing were conducted targeting blaNDM-1 genes.Medical records were reviewed and analyzed.Results Of the 52 CRKp strains,blaNDM-1 gene was detected in 28 strains.All NDM-l-producing strains were multidrug-resistant.All the 28 isolates were resistant to penicillin,cephalosporins,piperacillin-tazobactam,and imipenem.More than 75.0％ of these NDM-1-producing strains were resistant to aztreonam,trimethoprim-sulfamethoxazole,gentamicin,and meropenem (92.9％,26/28).NDM-1-producing isolates had higher carbapenem MICs than non-NDM-1-producing isolates.Most (82.1％,23/28) of the NDM-1-producing isolates were isolated from hematology-oncology ward.The most common underlying disease was hematologic malignancy (78.6％,22/28).Febrile neutropenia was found in 20 (71.4％) patients.No difference was found between NDM-1-producing and non-NDM-1-producing CRKp infection in terms of repeated hospitalization (P=0.202),prior antibiotic use (P=0.615),underlying diseases (P=0.856),and deep venous catheter (P=0.099).After the susceptibility results were available,37 patients received carbapenembased combination regimen.The mortality did not show difference between NDM-1 producing CRKp infections and non-NDM-1-producing CRKp infections,7.1％ (2/28) vs.12.5％ (3/24),P=0.625.Conclusions The NDM-1 carbapenemase producing Klebsiella pneumoniae is emerging in this hospital.NDM-1-producing strains are resistant to multiple antimicrobial agents,associated with higher carbapenem MIC value.However,no difference was found in the clinical features between the bloodstream infections due to NDM-1-producing strain and those due to non-NDM-1-producing strains.