Original Article Clinical Microbiology Distribution of β-Lactamase Genes Among Carbapenem-Resistant Klebsiella pneumoniae Strains Isolated From Patients in Turkey

Background: The emergence of carbapenem-resistant Klebsiella pneumoniae poses a se-rious problem to antibiotic management. We investigated the β-lactamases in a group of carbapenem-resistant K. pneumoniae clinical isolates from Turkey. Methods: Thirty-seven strains of K. pneumoniae isolated from various clinical specimens were analyzed by antimicrobial susceptibility testing, PCR for the detection of β-lactamase genes, DNA sequencing, and repetitive extragenic palindronic (REP)- PCR analysis. Results: All 37 isolates were resistant to ampicillin, ampicillin/sulbactam, piperacillin, piperacillin/tazobactam, ceftazidime, cefoperazone/sulbactam, cefepime, imipenem, and meropenem. The lowest resistance rates were observed for colistin (2.7%), tigecycline (11%), and amikacin (19%). According to PCR and sequencing results, 98 % (36/37) of strains carried at least one carbapenemase gene, with 32 (86%) carrying OXA-48 and