MOLECULAR CHARACTERIZATION OF CLINICAL AND ENVIRONMENTAL PSEUDOMONAS AERUGINOSA ISOLATED IN A BURN CENTER

Background and Aim:Pseudomonas aeruginosa is one of the major agents of nosocomial infections in burn centers.Therefore, The aim of this study was to characterize molecularly Pseudomonas aeruginosa isolates collected from environmental and burn patients.Methods:A total of 58 clinical and 20 environmental strains of the P. aeruginosa were collected from Beasat hospital of Hamadan, west of Iran, and identified via API 20NE. The antimicrobial resistance was tested by disk diffusion method as recommended by CLSI. Biofilm formation was quantified by the microtiter plate test. Pulsed Field Gel Electrophoresis (PFGE) was used to evaluate the genomic features of the isolated strains.Results:We found that 94.8% of clinical and 80% environmental isolates were capable of forming biofilm. The rate of MDR in clinical and environmental isolates was 51.7% and 40%, respectively. There was a significant correlation between multiple drug resistance and biofilm formation capability (p <0.05). PFGE typing showed 11 different clusters with two major clusters A with 30 (38.5%) and B with 14 (17.9%) members, containing up to 56.4% of all isolates. There was no relationship between biofilm formation ability and antibiotic resistance patterns with Pulsed-Field Gel Electrophoresis (PFGE) clusters.Conclusion:In this study, we demonstrated that clonal spread of environmental P. aeruginosa isolates is related to that of clinical isolates, being both associated with a high prevalence of the antibiotic resistance and biofilm formation ability. This study highlighted the prevention programs need to be implemented in the hospital environment to limit the transfer of P. aeruginosa in this burn units.

Keywords:

Psedumonas.aeruginosa , MDR , biofilm formation , antibiotic resistance , PFGE