Prevalence and Antimicrobial Susceptibility Patterns of ESBL, AmpC and Carbapenemase-producing Enterobactericeae Isolated from Hospitalized Patients in Azerbaijan, Iran

The current study was conducted to determine prevalence and antimicrobial susceptibility patterns, ESBL, AmpC and carbapenemase- producers among clinical isolates of Enterobacteriaceae. Three hundred and seven non-duplicative clinical isolates were collected from hospitalized patients in five medical centers in Azerbaijan, Iran. Initial screening for β-lactamase production was performed using disc agar diffusion according to Clinical Laboratory Standards Institute (CLSI) guidelines. Phenotypic confirmatory tests was done using total ESBL/AmpC confirm kit, KPC/MBL and OXA-48 confirm kit according to manufacturer’s instructions. The overall prevalence of ESBL, AmpC, and carbapenemaseproducing strains were 42.7% (131/307), 14.0%(43/307) and 4.9% (15/307), respectively. The prevalence of ESBLs was 38.35%, 64.9% and 35.7% for E. coli, K. pneumoniae and E. cloacae, respectively. Carbapenemase activity was only observed among 15 K. pneumoniae isolates and detected phenotypes include MBL (9/57, 15.8%), KPC (4/57, 7.0%), and OXA-48 (2/57, 3.5%). Fourteen out of 307 isolates (4.6%) were recognized to have ESBL or AmpC hyper-producer with decreased cell wall permeability phenotype. All 4 shigella strains were positive for ESBL and 4 isolates of P. mirabilis, 2 isolates of M. morganii and 1 seratia spp. were detected as AmpC producer. The only C. freundii strain isolated was positive for both ESBL and AmpC. This study reveals high prevalence of multidrug-resistant (MDR) β-lactamase-producing Enterobactericeae reaching 89.5%. Imipenem and meropenem showed potent antibacterial activities against all MDR β-lactamase-producers except for carbapenemase producers. After carbapenems, amikacin, piperacillin/tazobactam and amoxicillin/clavulanic acid were second the most effective drugs against β-lactamase-producing E. coli isolates.