BACTERIAL PROFILES AND ANTIMICROBIAL SUSCEPTIBILITY IN URINARY TRACT INFECTIONS: A SINGLE-CENTER OBSERVATIONAL STUDY

• Dr. Tomas H. Eriksson

  Department of Infectious Diseases, Karolinska Institute, Sweden

  Author

• Dr. Kelvin N. Adu

  Department of Medical Laboratory Science, University of Ghana, Ghana

  Author

Urinary tract infections (UTIs) represent a formidable global health challenge, characterized by their high prevalence and the escalating threat of antimicrobial resistance (AMR). This single-center observational study was meticulously designed to elucidate the prevailing microbial landscape responsible for UTIs and to meticulously characterize their susceptibility and resistance profiles to a panel of commonly utilized antimicrobial agents. A comprehensive cohort of 550 urine samples was systematically collected from patients presenting with a diverse array of UTI-associated symptomatology at a dedicated medical center in Duhok, Iraq, spanning the period from September 2024 to February 2025. Bacterial identification was rigorously performed utilizing a dual approach, encompassing conventional biochemical assays complemented by confirmatory analysis via the advanced VITEK 2 automated system. Antimicrobial susceptibility testing (AST) was concurrently executed using both the traditional manual disk diffusion method and the automated VITEK 2 system, with a subset of 190 samples undergoing comparative analysis to assess methodological concordance.

Of the samples rigorously analyzed, 249 patients were definitively diagnosed with UTIs based on significant bacteriuria. Contrary to some global trends, Staphylococcus epidermidis emerged as the most frequently isolated uropathogen (26.9%), followed by Staphylococcus aureus (20.1%), and Escherichia coli (16.5%). Other notable pathogens included Klebsiella species (8.8%) and Streptococcus pyogenes (5.6%). The VITEK 2 system revealed complete (100%) resistance to clindamycin, teicoplanin, and tetracycline across tested isolates, while linezolid and tigecycline consistently demonstrated 100% sensitivity. In stark contrast, the manual disk diffusion method exhibited greater variability in antibiotic performance, highlighting imipenem's exceptional effectiveness (98% sensitivity) and significant resistance to vancomycin (68%) and piperacillin (79%). Discrepancies between the two AST methods were particularly pronounced for vancomycin and levofloxacin, with manual disk diffusion often identifying a broader range of sensitive and resistant cases. These findings underscore the critical imperative for continuous, localized antimicrobial resistance surveillance and advocate for the judicious application of multiple testing methodologies to ensure accurate resistance profiling. Such comprehensive data are indispensable for guiding evidence-based empirical treatment protocols and for bolstering global efforts to combat the pervasive threat of multidrug-resistant infections.

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