Gender-linked variations in uropathogenic Escherichia coli identified by whole-genome sequencing.

OBJECTIVES

Uropathogenic Escherichia coli (UPEC) is the leading cause of urinary tract infections (UTIs) and a major contributor to antimicrobial resistance globally. This study compares the genomic and resistance profiles of UPEC isolates from male and female patients.

METHODS

Sixty-two UPEC isolates (31 male, 31 female) were characterized using antimicrobial susceptibility testing, whole-genome sequencing, and plasmid profiling. Analyses included sequence typing, phylogroup classification, plasmid replicon typing, and virulence and resistance gene screening.

RESULTS

Overall, 89% of isolates were ESBL producers, 27% were additionally carbapenem-resistant (CRE), and 77% were multidrug-resistant (MDR). ST131 was the most common sequence type (29%), especially among male-derived isolates (39%), associated with blaCTX-M-15, aac(6')-Ib-cr, and phylogroup B2. Female-derived isolates exhibited significantly higher CRE rates (35%), greater genetic diversity, and carriage of blaNDM-5 and blaOXA-48-like genes. IS26-flanked composite transposons carrying blaCTX-M-15, blaOXA-1, and aac(6')-Ib-cr were common, with chromosomal integration observed in ST648. IncF replicons predominated across the dataset, and female-derived isolates carried diverse plasmids, including IncA/C and IncX3. Virulence genes fimH, csgA, fyuA, and yehD were broadly distributed, revealing a conserved repertoire of virulence factors across both genders.

CONCLUSION

UPEC isolates differ by patient sex in clonal makeup, resistance mechanisms, plasmid composition, and virulence profiles. Male-derived isolates are associated with clonal, toxin-enriched lineages, while female-derived isolates show higher genomic plasticity and diverse resistance platforms. These findings support the integration of sex-based analysis into AMR surveillance and the need for tailored treatment approaches.