Biofilm Formation, Multidrug Resistance and Clinical Risk Factors Among Uropathogenic Enterobacterales in Iraq: A Cross-Sectional Study
DOI:
https://doi.org/10.31149/ijimm.v3i7.3028Keywords:
Urinary tract infection, biofilm, multidrug resistancemultidrug resistance, EnterobacteralesAbstract
Background: Urinary tract infections (UTIs) caused by multidrug-resistant (MDR) Enterobacterales are a growing problem in Iraq, and biofilm formation may help explain treatment failure and recurrence. Local data linking biofilm strength, resistance and clinical history are scarce. Objectives: To estimate the frequency of biofilm production among uropathogenic Enterobacterales, to describe antimicrobial resistance, and to test whether biofilm production and prior antibiotic use, recent hospitalization and recurrent UTI are associated with MDR. Methods: A prospective cross-sectional study of 200 consecutive, non-duplicate urinary isolates from symptomatic patients at Tikrit Teaching Hospital, Saladin, Iraq. Identification used standard methods; susceptibility used CLSI disk diffusion; MDR followed Magiorakos et al.; biofilm was measured by the 96-well crystal violet assay and graded as non-, weak, moderate or strong using Stepanović cut-offs. Associations were tested with chi-square, Kruskal-Wallis, trend tests and logistic regression. Results: Biofilm was produced by 122 isolates (61.0%): weak 17.5%, moderate 29.0%, strong 14.5%. MDR occurred in 135 isolates (67.5%), including 13 XDR (6.5%) and 4 PDR (2.0%). MDR rose with biofilm grade: 42.3% (non-producers), 68.6% (weak), 86.2% (moderate), 96.6% (strong); trend p < 0.001. Biofilm producers had higher MDR than non-producers (83.6% vs 42.3%; crude OR 6.95, 95% CI 3.61–13.41). In multivariable analysis, biofilm production (aOR 6.49, 95% CI 3.05–13.82), recent hospitalization (aOR 3.78, 1.57–9.10) and recurrent UTI (aOR 2.79, 1.11–7.01) were independently associated with MDR. Prior antibiotic use was independently associated with biofilm production (aOR 2.40, 1.27–4.52). Conclusion: Biofilm production was strongly associated with multidrug resistance among urinary Enterobacterales isolates, with MDR prevalence increasing alongside biofilm grade. Prior antibiotic use, recent hospitalization, and recurrent UTI were important associated factors.
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