Recent Advances in the Characterization of Uropathogenic Escherichia coli Associated With Resistance and Virulence...

Globally, urinary tract infections (UTIs) constitute a major concern as one of the most frequent bacterial infections and a major public health concern, particularly in developing countries like India. Among the various uropathogens, uropathogenic Escherichia coli (UPEC) is the principal causative agent of UTIs in both community-acquired and hospital-associated settings. UPEC strains are typically identified based on the presence of specific virulence factors (e.g., fimH, pap, sfa, afa) and phylogenetic grouping (mainly groups B2 and D), along with serotyping and molecular methods such as polymerase chain reaction (PCR), reported in previous studies. The increasing emergence of antimicrobial resistance, especially among UPEC isolates, has significantly complicated the management of UTIs and contributed to higher morbidity and healthcare burden. This review summarizes published literature on UPEC, with an emphasis on antimicrobial resistance patterns, virulence gene profiles, and biofilm-forming ability described across different studies. It also highlights the application of molecular techniques, particularly PCR, as reported in previous research for the detection of key resistance genes, such as blaTEM, blaSHV, blaCTX-M, and qnr, and aminoglycoside resistance determinants, as well as virulence-associated genes including fimH, pap, and sfa. Several studies, including reports from India and other regions, have documented a high prevalence of multidrug-resistant UPEC strains, commonly linked to extended-spectrum beta-lactamase production and, in some cases, emerging carbapenem resistance. Several studies have reported that approximately 50-80% of UPEC isolates exhibit biofilm-forming ability, and strong biofilm producers are often associated with higher levels of antimicrobial resistance and persistence of infection. The coexistence of multiple virulence factors further enhances the pathogenic potential of these strains, particularly in complicated and catheter-associated UTIs. Existing literature highlights the importance of continuous surveillance, rational antibiotic use, and effective infection control measures in managing UPEC-associated UTIs, particularly in tertiary care settings. Understanding the interplay between antimicrobial resistance, virulence determinants, and biofilm formation is essential for improving clinical outcomes and guiding therapeutic strategies in the management of UTIs.