Determinants of Multidrug Resistance Among Gram-Positive Uropathogens in Central Portugal: A 5-Year Retrospective Study.

Urinary tract infections (UTIs) are among the most common bacterial infections worldwide. Although Gram-negative bacteria predominate, Gram-positive cocci (GPC) are increasingly recognized as significant uropathogens. This retrospective study analyzed 655 patients with culture-confirmed GPC UTIs in a hospital in Central Portugal (2018-2022) to identify predictors of multidrug resistance (MDR). MDR was defined as resistance to three or more antimicrobial classes. The overall MDR prevalence was 83.7%, with Enterococcus spp. showing the highest MDR prevalence (98.2%). Multivariate analysis identified older age as an independent predictor of MDR, whereas Staphylococcus and Streptococcus species were associated with significantly lower odds compared to Enterococcus. A temporal increase in MDR risk was observed in 2021 and 2022. Despite the high overall resistance rates observed, oxazolidinones and cyclic lipopeptides retained near-complete activity against all GPC isolates, reinforcing their role as last-line therapeutic options.