Prevalence of CTX-M-3 Type Beta-Lactamase Genes in Various Clinical Specimens of Klebsiella pneumoniaein Sari, Iran

Introduction: The wideuse of beta-lactam antibacterial agents in the treatment of bacterial infections has increased bacterial resistance. Nowadays, one of the problems in the treatment of nosocomial infections is enzymes resistance to broad spectrum beta-lactamases among clinical isolates, especially Klebsiella pneumoniae.Over the past decade, CTX-M type enzymes have been recognized asthe most common type of broad-spectrum beta-lactamase in Europe, Canada, and Asia.The aim of this study was to evaluate the prevalence of broad-spectrum beta-lactamase-producingKlebsiella pneumoniae bacteria and to identify the CTX-M-3 gene by molecular method. Materials & Methods: Over a 9-month period, 130 Klebsiella pneumoniaewere isolated from different clinical specimens (urine, blood, ulcers) of infectious patients in Imam Khomeini Hospital, Sari, Iran. Their susceptibility to nine antibiotics used for gram-negative bacteria was measured by disk diffusion agar method. The extended-spectrum beta-lactamases (ESBLs) producing isolates were identified using a hybrid disc method. Moreover, strains producing CTX-M-3 enzyme were detectedby polymerase chain reactionmethod. Findings: The 48 (36.8%) isolates of Klebsiella pneumoniaewere the producer of ESBLs. Moreover, 22 (16.9%) of these cases contained the CTX-M-3 gene. Discussion & Conclusions: The obtained results of the currentstudy showed that the prevalence of ESBL producing strains resistant to quinolones is higher in Iran, compared to the developed countries