Molecular analysis of PmrA and PmrB genes in colistin-resistant Pseudomonas aeruginosa strains via PCR method

Abstract

Pseudomonas aeruginosa is one of the most common pathogens in hospitals. Along with the advent of various drug resistance patterns, rising resistance to colistin, the last alternative against this bacterium, is reported as a major clinical concern all over the world. Initially, Pseudomonas aeruginosa strains were identified by diagnostic tests including phenotypic method, growth at 42°C, Gram staining, culture on Blood Agar, EMB Agar, and biochemical oxidase, and catalase tests. The strains were confirmed using Microgen kit. Then, the resistance pattern of the identified strains was evaluated by Antibiogram. The presence of PmrA and PmrB genes were investigated by PCR method.A total of 60 strains of Pseudomonas aeruginosa were isolated and identified using microscopic, macroscopic and microbiological methods. The lowest resistance was observed against chloramphenicol and colistin antibiotics. Most of the strains harbored the PmrA and PmrB genes. The results of this study indicated an increasing trend in the resistance of the bacterium against different antibiotics. Accordingly, it is necessary to establish an infection control and therapeutic strategy in preventing the spread of such as similar resistant organisms.