Detection of Metallo-Beta-Lactamase-Encoding Genes Among Clinical Isolates of Pseudomonas aeruginosa in Qom Province

Carbapenem-resistant Pseudomonas aeruginosa has emerged as a serious problem in many hospitals and intensive care units. The purpose of this study was to determine the antibiotic susceptibility profile and the distribution of metallo-beta-lactamase genes among P. aeruginosa isolates from Qom province of Iran.

In this study, 200 P. aeruginosa isolates were collected from several clinical samples in hospitals affiliated to Qom University of Medical Sciences, Qom province, Iran. The antibiotic susceptibility of the isolates was tested by the Kirby-Bauer disc diffusion test and the distribution of MBL genes among carbapenem-resistant isolates was determined by polymerase chain reaction (PCR) method.

Among carbapenem non-susceptible isolates of P. aeruginosa, 38% (76 isolates) were multidrug resistant, 26% (52 isolates) were pan-drug-resistant and 5% (10 isolates) were extensive drug resistant. 52% of the isolates were resistant to carbapenems. Among carbapenem non-susceptible isolates of P. aeruginosa, 40 isolates (38.4%) exhibited MBL production. Of 40 MBL-producing isolates, 38 isolates (36.5%) contained the blaIMP gene and two (1.9%) isolates contained the blaVIM gene.

Outbreaks of MBL-producing P. aeruginosa isolates will be a serious problem in hospitals in the future and rapid identification of these isolates is necessary to control further dissemination of MBL resistance genes. This is the first report of the rates of MDR, XDR, PDR, and MBL-producing P. aeruginosa isolated from hospitals affiliated to Qom University of Medical Sciences in Qom province of Iran