Evolution of resistance patterns in Enterobacterales according to urinary tract infection diagnosis: implications for empirical therapy in a French emergency department.

BACKGROUND

Urinary tract infections (UTIs) caused by Enterobacterales are a major public health concern, with rising antimicrobial resistance (AMR) rates complicating empirical therapy. This study evaluated the evolution of resistance patterns in urinary Enterobacterales isolates from a French emergency department over an eight-year period (2013 vs. 2021-2022), focusing on implications for empirical treatment.

METHODS

A monocentric retrospective cohort analysis was conducted at the General Hospital of Melun, France. Urinary isolates from 2021 to 2022 were compared with 2013 baseline data. Resistance rates for cefotaxime, norfloxacin, trimethoprim-sulfamethoxazole (TMP/SMX), and fosfomycin were analyzed by species (Escherichia coli vs. other Enterobacterales) and clinical syndrome (e.g., pyelonephritis, cystitis). Statistical comparisons used chi-square or Fisher's exact tests.

RESULTS

Among 1,879 isolates (76% E. coli), resistance to cefotaxime (5.4%) and norfloxacin (8.7%) in E. coli significantly declined since 2013, while TMP/SMX resistance remained high (24.1%). Fosfomycin resistance was rare (1%). Resistance rates did not differ between colonizing and infecting strains. Complicated pyelonephritis isolates showed higher resistance (cefotaxime: 10%; norfloxacin: 12%) than uncomplicated cases, although these differences did not reach statistical significance.

CONCLUSION

Local AMR trends support empirical use of cefotaxime or fluoroquinolones for pyelonephritis but discourage TMP/SMX. Fosfomycin remains first-line for cystitis. These findings underscore the need for localized surveillance to guide stewardship efforts.

CLINICAL TRIALS: Not applicale.