Biofilm-producing and specific antibiotic resistance genes in Pseudomonas aeruginosa isolated from patients admitted to a tertiary care hospital, Bangladesh

Abstract

AimsBiofilms are responsible for persistent infections and antimicrobial resistance. Pseudomonas aeruginosa was investigated with its ability to form biofilm by detecting genes responsible to produce biofilms and biofilm-specific antimicrobial resistance. The association between antibiotic resistance and biofilm was investigated. MethodsThis cross-sectional study was conducted from July 2017 to December 2018. A total of 446 samples (infected burn, surgical wounds, and ETA) were collected from admitted patients of Dhaka Medical College and Hospital, Bangladesh. P. aeruginosa was isolated and identified by biochemical tests and PCR. Biofilm production by Tissue culture plate (TCP) method followed by detection of biofilm-producing genes (pqsA, pslA, pslD, pslH, pelA, lasR) and biofilm-specific antibiotic resistance genes (ndvB, PA1874, PA1876, PA1877) by PCR were done. Antibiotic susceptibility test was carried out by disc diffusion method; for colistin agar dilution method of MIC was followed. ResultsAmong 232 (52.02%) positive strains of P. aeruginosa, 24 (10.30%) produced biofilms in TCPM. Among biofilm-producing genes, pqsA was the highest (79.17%). pslA and pelA were 70.83%, pslD 45.83%, pslH and lasR 37.5%. Among biofilm-specific antibiotic resistance genes, 16.67% were ndvB, and 8.33% were PA1874 and PA1877. Biofilm-forming strains were significantly resistant to colistin. ConclusionDetection of biofilm-forming genes may be a good tool for the evaluation of biofilm production, which will help in prompt and better management of chronic or device-associated infections.