DETECTION OF CLASS 1 INTEGRONS AMONG GRAM NEGATIVE BACILLI ISOLATED FROM SPUTUM CULTURES OF PATIENTS WITH RESPIRATORY SYMPTOMS REFERING TO TEACHING HOSPITALS IN AHVAZ, IRAN

Background and Aim:Diffusion of antibiotic resistance genes by horizontal gene transfer has led to the fast emergence of multidrug resistance (MDR) among bacteria. Multiple classes of integrons are effective genetic elements which play a significant role in acquisition and nosocomial dissemination of resistance factors in different Gram-negative bacteria, Pseudomonas aeruginosa (P.aeruginosa ) and Acinetobacter baumannii ( A. baumannii ) strains.Methods:A total of 110 sputum samples that were collected from hospitalized patients with respiratory symptoms were examined in this study. Identification of the isolates were performed by standard biochemical tests. Susceptibility test of them to seven antibiotic disks was carried out by Kirby-bauer disk diffusion method according to CLSI guidelines and finally the class 1 integron genes were detected by PCR.Results:Maximum resistance rate for gram negative isolates was observed for Ceftazidime, Co-trimoxazole and Cefotaxime with 89% , 87% and 82% respectively. 4 P. aeruginosa ( 10% ) , 7 A. baumannii ( 17% ) and 2 Enterobacteriaceae (5%) were resistant to Imipenem. Out of 6 P.aeruginosa and 9 A. baumannii isolates, 2 isolates ( 33.3% ) and 3 isolates ( 33.3% ) were positive for class 1 Integron gene, respectively. While all Enterobacteriaceae isolates (100%) were negative for class 1 Integron gene. Class1 integrons were detected among of MDR isolates.Conclusion:The results of this study showed that for prevention of spreading these MDR isolates, monitoring of drug resistant isolates with investigating presence of class 1 integron and antibacterial stewardship program is necessary.

کلیدواژه ها:

Class 1 integron ، multidrug resistance ، Pseudomonas aeruginosa ، Acinetobacter baumannii ، Enterobacteriaceae