Molecular Characterization and Antibiotic Resistance Pattern of Nosocomial Clinical Isolates in Southeast of Iran

Background and objectives: nosocomial infections caused by antibiotic resistant bacteria is a life threatening health challenge. this study aimed to determine the frequency of antibiotic resistance genes in clinical isolates from hospitals of zahedan, southeast of iran. methods: overall, 818 isolates were collected from different hospital wards. the isolates were identified using conventional microbiological and biochemical tests. antibiotic susceptibility pattern was assessed by agar disc diffusion method and determination of minimum inhibitory concentration of a number of antibiotics. multiplex pcr was performed using specific primers for the detection of resistance genes. results: the most common species were staphylococcus aureus (25%), klebsiella pneumoniae (22%) and pseudomonas aeruginosa (14%). the rate of methicillin resistance among s. aureus, s. epidermidis and s. saprophyticus was 60%, 43% and 24%, respectively. in addition, 28.5% of enterococci isolates were vancomycin resistant. among gram-negative bacteria, 45% of a. baumannii and 24% of p. aeruginosa were identified as esbl. a high level of resistance to ampicillin (96%), cefotaxime (89%), gentamicin (89%) and sulfamethoxazole-trimethoprime (60%) was observed in k. pneumoniae. conclusion: our results highlight the urgent need for an eradication program and a surveillance plan for preventing increased emergence of antibiotic resistant bacteria in the study area.