Phenotypic and Molecular Characterization of Plasmid Mediated AmpC among Clinical Isolates of Klebsiella pneumoniae Isolated from Different Hospitals in Tehran.

INTRODUCTION Klebsiella pneumoniae is one of the main opportunistic pathogens which can cause different types of infections. Production of beta-lactamases like AmpC and ESBL mostly lead to beta-lactam resistance in these Gram-Negative bacteria. The aim of this study was the detection of AmpC-producing K. pneumoniae in clinical isolates. MATERIALS AND METHODS Three hundred and three isolates of K. pneumoniae were identified. Double disc method including cefoxitin with cefepime and using boronic acid with cloxacillin were performed as two phenotypic methods for detection of AmpC. Amplification of AmpC gene was performed by PCR. RESULTS Eight and three isolates showed positive results in double disc method and by using boronic acid with cloxacillin, respectively. Five isolates had specific band for AmpC gene after electrophoresis. CONCLUSION Our results were indicated the low prevalence of AmpC-producer-K. pnemoniae in Iran. On the other hand these two tested phenotypic methods showed low sensitivity for detection of AmpC.