Study of antimicrobial resistance profile and efflux mediated drug resistance in clinical isolates of Pseudomonas aeruginosa detected by ethidium bromide-agar Cartwheel method

Abstract

Background: Development of antibiotic resistance or multidrug resistance (MDR) is one of the major causes of treatment failure of bacterial infections and has rapidly evolved into a threat to global health care. Bacterial efflux pumps play a significant role in the development of antibiotic resistance. This study evaluates the prevalence of efflux pump- mediated drug resistance in clinical isolates of P. aeruginosa.Methods: Clinical isolates (n=100) of P. aeruginosa were collected from various clinical laboratories in Kerala and their efflux mediated drug resistance detected by the ethidium bromide (EB) agar Cartwheel method.Results: The EB agar cartwheel method of screening revealed efflux activity in 17% (n=17) strains. The efflux activity was revealed at a minimum concentration of EB at 0 mg/l. P. aeruginosa strains showed the highest activity up to a concentration of 2.5 mg/l.Conclusions: This study discusses the emergence of efflux pump- mediated drug resistance in P. aeruginosa from various clinical samples. Our results showed that 17% drug resistance in P. aeruginosa is attributable to efflux related mechanisms.