Antibiotic Resistance Patterns of Common Gram-negative Uropathogens in St. Paul’s Hospital Millennium Medical College

Abstract

BACKGROUND: The resistance of bacteria causing urinary tract infection (UTI) to commonlyprescribed antibiotics is increasing both in developing and developed countries. Resistance has emergedeven to more potent antimicrobial agents. This study was undertaken to determine the current antibioticresistance pattern among common bacterial uropathogens in St.paul’s Hospital Millennium MedicalCollege.METHODS: Using cross sectional study design, a total of 217 female and 207 male participants wereconsecutively recruited. Mid-urine samples were collected from all patients using wide mouthed urinecup. Inoculation was performed onto blood agar and MacConkey agar symoultaniously, and isolatedorganisms were identified by conventional methods. Antibiotic susceptibility was done by Kirby Bauerdisk diffusion method. Thirteen different antibiotics representing different families of antibiotics weretested on all isolated organisms.RESULT: Of the total 424 samples, 95(22.4%) showed significant growth. Gram negative organismstotaled 85(20.05%), and 10(2.4%) isolates were gram positive. The most frequently isolated gramnegative bacterium was E. coli followed by Protues and Klebsiella spp. 53(12.5%), 8(8.4%), and 7(7.4%)respectively. Resistance to Tetracyclin, Ampicilin, Amoxycilin and Nalidixic Acid was more than 70% ofall isolates of E.coli strains. There was relatively low resistance rate to Nitrofurantoin, Gentamycin andTrimethoprim-Sulfamethoxazole. However, there was emerging resistance to Ciprofloxacilin andCeftriaxone especially for common bacteruria.CONCLUSIONS: In this study setting, resistant rates to Tetracyclin, Ampicilin, Amoxycilin andNalidixic Acid were high. Since most isolates were sensitive for Nitrofurantoin, Gentamycin andTrimethoprim-Sulfamethoxazole, they are considered as appropriate antimicrobials for empiricaltreatment for urinary tract infections with the absence of culture and sensitivity setting. Increasingantibiotic resistance trends indicate that it is imperative to rationalize the use of antimicrobials in thecommunity and use these conservatively.