Characterization of virulence factors and antibiotic resistance pattern of uropathogenic Escherichia coli strains in a tertiary care center

<p><strong>Background</strong>: Urinary tract infections (UTIs) are the most prevalent bacterial infection in humans. The uropathogenic E. <em>coli </em>(UPEC) express a wide range of virulence factors that contribute to their pathogenicity<span>.</span><span> The emergence of Multidrug resistance(MDR)-associated UTI is increasing off late</span>. Hence this study was undertaken to monitor the distribution of virulence factors among UPEC strains and to note the antibiogram, outcome and type of associated UTI.</p> <p><strong>Methods</strong>: A prospective cross-sectional time-bound study of 6 months was done on clinically significant <span>urinary </span>isolates of <em>Escherichia</em> <em>coli</em>. <span>Detection of haemolysin production and serum resistance</span><span> was done by </span><span>phenotypic methods. Genotypic characterization of the virulence genes (papC, iutA, hlyA, cnf1) was done by multiplex PCR. </span>Demographic data, clinical history, antibiogram and type of UTI were collected from clinical case records.</p> <p><strong>Results</strong>: 75 <em>E</em>. <em>coli</em> isolates from patients with suspected urinary tract infections were included. <span>Females had a higher preponderance of UTI (66.7%).93% of the patients were adults and the remaining 7% were from the paediatric population.  24 (32%) isolates showed haemolysis by plate haemolysis method, and all 75 (100%) isolates were serum resistant. </span>Out of 75 isolates, 65 were positive for at least one of the four targeted genes, while the remaining 10 isolates were negative for all 4 genes. <span>Multidrug resistance was found in 40 (53.3%) isolates. 97.4% of the UTI cases had a favourable clinical outcome at discharge. Mortality due to urosepsis was 2.6%.</span></p> <p><strong>Conclusion</strong>:<span> The association of hemolysin production with resistance to imipenem and norfloxacin in UPEC strains was significant. T</span><span>he presence of the hlyA gene is positively associated with ceftazidime resistance. </span><span>Nitrofurantoin, piperacillin tazobactam and cefaperazone sulbactam maybe suitable candidates for empirical therapy of UTIs. Drugs like aminoglycosides, carbapenems and fosfomycin may be used as reserve drugs in the treatment of MDR-UTI</span><span>. However, inappropriate usage can gradually increase antibiotic resistance. Hence, proper selection of antibiotics in hospitals taking into account the local antibiogram is needed to reduce the emergence of antibiotic resistance.</span></p>