)-I, aac(3)-III and Integron Class 1 of MDR Pseudomonas aeruginosa in Tehran Hospital

Pseudomonas aeruginosa is a gram-negative, obligate aerobic bacil which is widespread in world and causes burned hospital infections in humans. Multidrug resistant strains of Pseudomonas aeuginosa (MDR) have been emerged as alarming nosocomial pathogens among burned patients in Tehran (Iran). Integrons play important role in drug resistant in bacteria. Aminoglycosides are common antibiotics which were sometimes used to treatment against pseudomonas infections. The purpose of this study was to determine genes aac(6/)-I, aac(3)-III and Integron Class1 in MDR Pseudomonas aeruginosa isolates of Motahari burned hospital in Tehran during 2013-2014. The bacterial isolates were collected from 100 patients with burn wound infections and P. aeruginos species were identified by standard bacteriological tests. Antimicrobial susceptibility tests were carried out according to Laboratory Standards Institute (CLSI, 2013). PCR was carried out for the detection of class1Integrons and aac(6/)-I, aac(3)-III genes. Minimum inhibitory concentration (MIC) values of all isolates to aminoglycosides were determined by the micro broth dilution method as were described by the CLSI2013 guideline. A number of 100 hospitalized patients in the burn ward were assessed, resistance rates to various antibiotics were as follows: Gentamycin (83%), Amikacin (87%), Tobramycin (83 %). The PCR results showed that 90% P. aeruginos isolates harboured class 1 integrons. A significant correlation was obtained between the presence of integrons class I and resistance to Gentamycin (p < 0. 01).The results of PCR indicated that rate of frequency resistant genes were aac (6)-I (78%), aac (3)-III (93%). Optimum prescription of antimicrobial drugs, control of infection and attention to antibiograma are recommended in order to prevention the increasing outbreak of drug resistant in the burned centers setting in this study. Furthermore, the high frequency of class 1 integrons among MDR isolates might be responsible for dissemination of antibiotic resistance genes. Resistant to aminoglycosides in P. aeruginosa remains as major problem in Iran and world. Therefore is a necessary considerable serious surveillance system for prevention drug resistance.