Detection and characterization of antibiotic resistant and biofilm producing clinical isolates of Acinetobacter baumannii

Abstract

Acinetobacter baumannii is an opportunistic pathogen that affects persons with weakened immune systems and causes nosocomial infections due to its antibiotic resistance. Because of the global proliferation of multidrug resistance bacteria and biofilm development-ability to survive on dry surfaces aid in proliferation in a variety of healthcare environments, this study focuses on identifying the relevant gene for biofilm development and antibiotic resistance. Acinetobacter baumannii clinical isolates (150) were recovered from BSMMU in Dhaka. For A. baumannii pure strain identification; Biochemical tests and PCR (Polymerase chain reaction) were performed and validated using Agarose gel-electrophoresis. After verifying pure strains, the antibiotic susceptibility test was performed using the Kirby-Bauer disc diffusion method and biofilm development was assessed using the 96-well microtiter plate method. Furthermore, PCR was used to screen both the carbapenem resistance gene and the biofilm generating gene. Out of 150 isolates, 109 were verified true positive with PCR analysis, enforcing additional research. AST was performed with medicines from several groups, the majority of them were MDR and mostly, Carbapenem resistant. PCR was performed for screening both MDR gene and biofilm producing gene, with 15.59% NDM gene being positive and the others yielding no significant results. Biofilm-related genes such as bap, blaPER-1, csuE, and ompA were reported to be frequent at 88.98%, 56.88%, 84.40%, and 83.48%, respectively, in all biofilm generating isolates (24.77%) strong, (33.02%) moderate, and (10.09%) weak, (31.19) % non-biofilm forming. Our study focused on the prevalence and antibiotic -resistant pattern of the MDR A. baumannii, which is more common in clinical isolates, as well as biofilm producing capability and Biofilm-forming genes. It appears that effective surveillance and control actions are required to halt the CRAB outbreak in our country and healthcare settings.