Antimicrobial Susceptibility Pattern of Extended Spectrum Betalactamase Producers In Gram-Negative Urogenital Isolates In Kano, Nigeria

The emergence of resistant strains of urogenital extended spectrum beta-lactamase producing isolates has presented a serious set back in the treatment option for urogenital tract infection. Emergence and spread of these strains resulted in treatment failure and disease complications. This study was aimed to determine the prevalence of ESBL producers in Gram-negative urogenital isolates and their susceptibility to 10 selected antimicrobial agents [aztreonam, cefoxitin cefepime, levofloxacin, ciprofloxacin, kanamycin, gentamicin, streptomycin, clarithromycin and erythromycin.]. A total of 500 isolates of Escherichia coli, Proteus mirabilis, Proteus vulgaris, Klebsiella pneumoniae, Klebsiella aerogenes, and Pseudomonas aeruginosa were collected from Microbiology Department of Aminu Kano Teaching Hospital (AKTH), Kano. The isolates were tested against third generation cephalosporins using Clinical Laboratory Standard Institute (CLSI) recommended, WHO modified Kirby-Bauer disc diffusion method. Isolates with reduced susceptibility to cefpodoxime, cefpotaxime and ceftriaxone were considered to be a possible ESBL producers and were confirmed using double disc synergy method. The number of ESBL producers in 500 urogenital gram negative isolates was found to be 77/500 (15.4%). Out of the 77 ESBL producing urogenital isolates 47 (61%) isolates which include E. coli, (33, 70%), K. aerogene (3, 6%), K. pneumoniae (6, 13%), P. mirabilis (9%) and P. aeruginosa (2%) were subjected to antimicrobial susceptibility test using CLSI recommended, WHO modified Kirby Bauer disc diffusion method. Zone diameters were interpreted using European Committee on Antimicrobial Susceptibility Testing breakpoint tables for interpretation of zone diameters. The overall result demonstrates high resistance rate (≥60%) to the selected antibiotics. The isolates were found to be more susceptible to Cefoxitin (40%), and Cefepime (38%); followed by Kanamycin (32%), Levofloxacin (28%), and Ciprofloxacin (28%). With Gentamicin (16%) Clarithromycin (11%), Streptomycin (9%), Aztreonam (4%) and Erythromycin (2%), showing low antimicrobial activity against the isolates. The result of this study shows that multidrug resistant ESBLs producing strains are present among urogenital bacterial pathogens in Kano. It is recommended that urogenital ESBLs isolates treatment option be based on antimicrobial susceptibility results.