Carbapenem-hydrolysing β-lactamase KPC-2 in Klebsiella pneumoniae isolated in Rio de Janeiro, Brazil

Abstract

Objectives: The aim of this study was to characterize the KPC-type carbapenem-hydrolysing β-lactamase, extended-spectrum β-lactamases (ESBLs) and class 1 integrons among nosocomial Klebsiella pneumoniae isolated in Rio de Janeiro, Brazil. Methods: MICs were determined and isolates were screened for ESBLs, metallo-β-lactamases (MBLs) and class A carbapenemase-producing phenotypes. The main β-lactamases resistance genes (blaTEM, blaSHV, blaCTX-M, blaKPC, blaIMP and blaVIM) and class 1 integrons were detected by PCR followed by DNA sequencing. The genetic relatedness of isolates was determined by PFGE. Results: All K. pneumoniae isolates were positive for ESBL and class A carbapenemase production and negative for MBL production. All isolates were resistant to all β-lactam antibiotics, ciprofloxacin and gentamicin, being susceptible only to tigecycline and polymyxin B. The blaKPC-2, blaCTX-M-1, blaCTX-M-2, blaCTX-M-8 and blaSHV-11 genes were detected. PFGE analysis revealed two clonal types among KPC-producing isolates, both identified in the same hospital. Conclusions: Our findings should alert medical authorities to implement stringent methods for the detection and spread control of emerging KPC-2 carbapenemases in the hospital setting in Brazil. © The Author 2008. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved.