Bacteriology of Urinary Tract Infection Among the Patients Visiting Tribhuvan University Teaching Hospital (TUTH)

Abstract

Urinary Tract Infection (UTI) is one of the most common diseases encountered worldwide and is a major public health problem in terms of morbidity and financial costs. A prospective cross-sectional study was carried out from Aug 2012 to Jan 2013 in department of microbiology at TUTH. A total of 1,063 urinary tract samples (Mid stream urine, catheter, and suprapubic aspirate) from patients visiting TUTH were included. Samples were processed for routine microscopy and culture and the organisms were identified by standard microbiological methods. Antibiotic susceptibility testing was done by Kirby-Bauer Disk Diffusion method according to CLSI guidelines. ESBL producing organisms were detected by Combination Disk method, MBL producing organisms were detected by EDTA-Imipenem combined disk assay and Methicillin resistance Staphylococcus aureus (MRSA) was detected by Cefoxitin disk. Of the total 1,063 samples processed, 276(26.0%) samples showed significant bacteriuria. Twelve different genera of bacteria were isolated from total 276 isolates among which E.coli (57.6%) was the most common isolate followed by Staphylococcus aureus (14.1%), Klebsiella spp (6.2%), Enterococcus faecalis (5.4%), Staphylococcus epidermidis (3.9%), Pseudomonas aeruginosa (3.3%), Acinetobacter spp (2.5%), Enterobacter spp (2.2%), Burkholderia cepacia Complex (1.8%), Staphylococcus saprophyticus (1.4%), Citrobacter spp (1.1%) and others (<1%). Among the gram negative isolates (210), majority (61.0%) of the isolates were found MDR. Nearly 58% of MDR isolates were ESBL producer and 5% were MBL producers. Most of the ESBL and MBL producing isolates were detected in E.coli and Klebsiella spp respectively. Most of the Gram negative bacterial isolates were sensitive to Polymyxin B followed by Imipenem, Amikacin and Cotrimoxazole. Among the gram positive isolates (66), 42.4% of isolates were MDR. All the MDR S. aureus (21/39) isolates were found MRSA. All Gram positive isolates were sensitive to Vancomycin and Teicoplanin followed by Amikacin. Among the oral antibiotics tested, Nitrofurantoin was found to be the most sensitive antibiotic for gram positive as well as gram negative bacterial isolates. It revealed that E. coli is the predominant Uropathogens in TUTH, Nepal. There is an increasing resistance to many antibiotics in the both community and hospital settings. Now-a- days, ESBL and MBL producing uropathogens are emerging.

Keywords: Antimicrobial Susceptibility Profile, ESBL, MBL, MDR, MRSA, UTI