Plasmid Profile and Curing, Biofilm Detection among Esbl Producing Isolates of Acinetobacter Species

Objective: The aim of the present study is to evaluate the plasmid profile and curing in extended spectrum beta-lactamases (ESBL) producers and know the association of biofilm formation among ESBLs. Methods: Standard disk diffusion method (Kirby Bauer’s method) was performed to know the sensitivity and resistance patterns for commonly used antibiotics and clinical laboratory standard institute (CLSI) recommended confirmatory phenotypic method was used to confirming ESBL producers. 56 ESBL producers were subjected to plasmid profiling and curing. The tube (qualitative) and microtitre (quantitative) methods were performed to detect the biofilm formation. Results: In all ESBL producers, a single plasmid was found with approximately 21, 226 bp. After plasmid curing, the resistance patterns against the third generation cephalosporin group of antibiotics were transformed into susceptible for all bacterial isolates. In tube method, 11 (19.64%) isolates were strong adherent, 08 (14.28%) were either weakly adherent or non-biofilm producers. In the microtitre plate method, 09 (16.07%) were considered as positive, and 47 (83.92%) were considered as negative for biofilm formation. Conclusion: We found a single resistant plasmid in all isolates and after curing of plasmids, the transformation of resistance to susceptibility against third generation drugs were observed. So, we concluded that ESBL mediated antimicrobial resistance mechanisms in Acinetobacter spp. is maybe plasmid-mediated in the tested isolates. However, there was no association found between biofilm producers and ESBLs, this baseline information will be helpful to study more in this area.