Relationship between antimicrobial resistance and virulence factors in uropathogenic Escherichia coli isolates from Ramadi, Iraq: phenotype and genotype identification.

BACKGROUND

Uropathogenic Escherichia coli (UPEC) is the most predominant pathogen that causes severe urinary tract infections (UTIs). Their therapeutic options are limited due to the rising of antibiotic resistance.

OBJECTIVE

The aim of the study was to evaluate the level of antibiotic resistance profile, redundancy of virulence genes, and their correlation.

METHODS

41 UPEC isolates were collected from patients diagnosed with UTI, identified by the standard microbiological analysis, and tested for susceptibility to 12 antibiotic agents using the Kirby-Bauer method. The ability of UPEC isolates to produce biofilm, hemolyze and cause clumping of blood was determined. Virulence genes were detected by PCR analysis.

RESULTS

The percentage of UPEC isolates was higher in females (78.1%) than in males (21.9%). UPEC isolates showed a high degree of resistance towards Ceftriaxone (90.2%), Cefepime (90.2%), Ciprofloxacin (82.9%), Levofloxacin (82.9%), and Trimethoprim-Sulfamethoxazole (80.4%). Biofilm formation (87.8%) and hemagglutinin activity (80.4%) were the most predominant virulence markers expressed in UPEC and showed a high degree of correlation with the antibiotic resistance profile. PCR analysis showed that fimH (85.3%) was the most prevalent gene detected in UPEC isolates, followed by aac3-II (80.4%) among the five genes tested, blaTEM, aac3-II, sul2, hlyA, and fimH. The correlation between antibiotic resistant patterns and the presence aac3-II gene was significantly high. The resistance to the sulfonamides' combined antibiotic was highly correlated with the presence of sulf2 gene.

CONCLUSION

Antimicrobial resistance was significantly linked to phenotypic and genotypic virulence factors. These results will aid in elucidating the pathogenicity of UTIs and guiding treatment decisions.