Drug resistance profile of biofilm forming Pseudomonas aeruginosa isolated from aquatic environment in South Eastern Nigeria

Abstract

This study was carried out to determine drug resistance pattern of biofilm forming Pseudomonas aeruginosa isolated from aquatic environment in South Eastern Nigeria. A total of 272 water samples from Ezillo Water Treatment Plant were examined. Bacteriological analysis of the samples was done using standard microbiological techniques. Biofilm formation was carried out using crystal violet binding assay method while antibiotic studies of was determined using Kirby-Bauer disk diffusion method following Clinical Laboratory Standards Institute (CLSI) guidelines. Plasmid curing analysis was done using acridine orange treatment. The statistical analysis was carried out using statistical analysis software (SAS). A total of 223 isolates of Pseudomonas aeruginosa were confirmed. Data revealed that the level of occurrence was high (85.11%) among the various treatment units in the plant. Biofilm formation among test isolates was high 128 (57.40%). Biofilm forming isolates were resistant to imipenem (39.45%), ceftaxidime (68.79%), ciprofloxacin (69.89%), ofloxacin (70.77%), ertapenem (84.33%) cefepime (85.11%), ticarcillin (89.43%), amikacin (90.44%), gentamicin (91.97%), cefotaxime (93.79%) and were completely resistant to amoxicillin\\clavulanic acid, tobramycin, oxacillin and aztreonam. The multiple antibiotic resistance index (MARI) ranged from 0.64 to 0.93. We report the occurrence of multidrug resistant Pseudomonas aeruginosa in water samples from Ezillo Water Treatment Plant in South Eastern Nigeria, which could be a critical source of infections in the region.