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

OBJECTIVES

The aim of this study was to characterize the KPC-type carbapenem-hydrolysing beta-lactamase, extended-spectrum beta-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-beta-lactamases (MBLs) and class A carbapenemase-producing phenotypes. The main beta-lactamases resistance genes (bla(TEM), bla(SHV), bla(CTX-M), bla(KPC), bla(IMP) and bla(VIM)) 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 beta-lactam antibiotics, ciprofloxacin and gentamicin, being susceptible only to tigecycline and polymyxin B. The bla(KPC-2), bla(CTX-M-1), bla(CTX-M-2), bla(CTX-M-8) and bla(SHV-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.