prevalence of per and veb type extended spectrum betalactamases among multidrug resistant acinetobacter baumannii isolates in north-west of iran

objective(s): drug resistant acinetobacter baumannii have emerged as a major problem in many hospitals and intensive care units. various types of extended spectrum beta-lactamases (esbls) are responsible for resistance to beta- lactam antibiotics in different parts of the world. the objective of this study was to determine the prevalence of integron class1 (int 1) and esbl types per-1, per-2 and veb-1 among a. baumannii strains isolated from tabriz, north-west of iran.   material and methods: a total of 100 a. baumannii isolates collected from different clinical samples were included in the study. antimicrobial susceptibility profiles were determined using the kirby bauer disk diffusion method. production of esbl was investigated by testing resistance against ceftazidime, cefotaxime, ceftriaxone and verified by double disk synergy test. dna was extracted from the isolates and the frequency of int 1 and esbl types per-1, per-2 and veb-1 were determined by pcr using specific primers. results: among 100 a. baumannii isolates screened, 80 isolates were multidrug-resistant and 70 isolates were positive for esbl production. pcr screening revealed that 74 % of the isolates contained class 1 integron, 51% were positive for per-1 gene, 10% positive for veb1 whereas none of the isolates were positive for per2 type gene. conclusion: this is the first report of esbl types veb and per in a. baumannii from north west of iran. the results of this study demonstrated high prevalence of per-1 and veb-1 type esbls among a. baumannii isolates in the study region and reminded the necessity of appropriate infection control strategy to prevent further spread of infection by these organisms.