PHENOTYPIC & MOLECULAR CHARACTERIZATION OF AMPC Β-LACTAMASES AMONG ESCHERICHIA COLI, KLEBSIELLA SPP. & ENTEROBACTER SPP. ISOLATED FROM AL-HUSSEIN TEACHING HOSPITAL IN THI-QAR GOVERNORATE

Abstract

In this study,101 Escherichia coli, Klebsiella spp. and Enterobacter spp. isolated from clinical and hospital environment specimens of Al-Hussein Teaching Hospital in Dhi-Qar governorate, were analyzed for AmpC B-lactamase using phenotyping methods and polymerase chain reaction(PCR). The purpose of this study was to detect and characterize AmpC β-lactamases in these isolates were not study in Al-Hussein Teaching Hospital by another researchers. AmpC β-Lactamase was initially detected by phenotyping methods. Out of 101 of isolates, 80 (79.2%) were β-lactam resistant, 32 (31.6 %) isolates were deemed resistant and intermediate to cefoxitin were suspected as AmpC producer, 23 (22.7 %) of isolate were identified as AmpC β- lactamase producer, whereas, 5 (4.9 %) isolates were identified as inducible AmpC β- lactamase . Plasmid mediated AmpC genes were detected by conventional PCR. Only 11 (10.9 %) of Escherichia coli, 2 (1.9 %) of Klebsiella spp. and 5 (4.9 %) of Enterobacter spp. gave positive results with AmpC gene. Results of antibiotic susceptibility revealed that AmpC carrying isolates had high resistance to Cefotaxime, Aztreonam, Amoxiclave, Carbencillin, Pipercilin, Nalidixic acid, Ampicillin, Cotrimethoxazole, Ciprofloxacin and Levofloxacin. The study also revealed that Norfloxacin, Amikacin, Ciprofloxacin and Levofloxacin was found to be effective against 100% of the AmpC harboring Enterobacter spp. Additionally, Imipenem and Meropenem were found to be effective against 60% of the AmpC harboring E. coli, 50% of Klebsiella spp. and 80% of Enterobacter spp.