Distribution and phylogenetic analysis of bacterial isolates from Urinary Tract Infection patients of Pakistan

Urinary tract infections (utis) are the second most common infections that infect millions of people worldwide. uti can occur anywhere along the urinary tract and may cause symptomatic infection to complete renal failure. most utis are caused by escherichia coli (e. coli) which exhibit a high degree of both phenotypic and genetic diversity and disseminated in various geographical regions of the world. the aim of the present study was to determine the foremost pathogen responsible for utis and to investigate its genetic lineage in pakistan. the clean clutch midstream urine samples of 174 (78% females and 22% males) patients with clinical symptoms of uti from gujranwala and faisalabad districts of pakistan,were cultured for the isolation of bacterial agents. the bacterial species were identified by standard biochemical and molecular tests. out of total 174 samples,84 (48%) were found urine culture positive with cfu >104. among them,e. coli was the most frequent bacterium (n=51,60.7%) isolated from patients followed by pseudomonas sp. (n=13,15.4 %),klebsiella sp. (n=9,10.7%),proteus sp. (n=7,8.3%),and staphylococcus aureus (n=4,4.7%). to perform phylogenetic analysis of e. coli isolates,partial 16s rrna was amplified and sequenced. sequences were aligned and edited using codoncode aligner. phylogenetic tree constructed on the basis of 613 bp fragment of 16s rrna,using mega6.1 through neighbor-joining method revealed that majority of e. coli isolates (n=16) had close relatedness with established uropathogenic strain st-131. eight isolates resembled closely and grouped with each of st-101 and st-14 strains while seven isolates showed high similarity with st-648 strain followed by st-73 strain indicating genetic closeness with four local isolates. it is concluded that genetically diverse uropathogenic e. coli are prevalent in the clinical setting of pakistan in the studied area. the data of these isolated e. coli strains would improve our understanding about the epidemiology of this organism and may serve as baseline information for future researchers in the days ahead. copyright 2016 zoological society of pakistan.