Background and Aim :
Pseudomonas aeruginosa is a nosocomial opportunistic pathogen and responsible for ۱۰-۱۵% of nosocomial infections. P. aeruginosa is known as an acute problem in nosocomial infections due to innate resistance to many antibiotics, great capability to become resistant to all effective antibiotics, cause complications in treatment and also increase mortality rates.Methods : The samples were bacterial archive of microbiology department of medical university, and then were distinguished as P. aeruginosa by common microbiological methods, biochemical tests and type-specific primers by polymerase chain reaction (PCR) method. Antibiotic sensitivity test against carbapenems (imipenem and meropenem), was done for all the isolates with the Kirby-Bauer disk diffusion method according to CLSI guidelines. At the end the phenotypic tests were performed for the identification of class I- III integron genes for each isolate and also the genotypic analysis including pcr was done.Results : From ۷۵ samples of the recent study, ۳۲ isolates (۴۲.۶۷%) were resistant to imipenem. According to
PCR results among ۳۹ imipenem resistant isolates, ۲۹ isolates (۹۰.۶%) harbored class I integron, ۸ isolates included class II integron and none of them harbored class III integron. It is considerable that ۲ imipenem resistant isolates (۶.۲۵%) were missing any integron and ۲ resistant isolates just included class II integron but had no class I integron. Also, from ۲۲ meropenem resistant isolates, ۱۹ isolates (۸۶.۳%) harbored class I integron, ۷ isolates (۳۱.۸%) included class II integron and one isolate harbored none of the integrones. Additionaly, none of the isolates carried class III integron. Among meropenem resistant isolates, ۶ isolates (۲۷.۲%) were positive for class I and II integrons, while ۳ sensitive isolates (۹.۴%) also harbored both class I and II integrons.Conclusion : According to the results of spearman’s test, resistance to imipenem and meropenem among P. aeruginosa isolates is increasing and this resistance has a remarkable relationship between existence of class I and II integrons. Hence, preventive measurements are necessary in order to control the distribution of resistant isolates.