TOPLINE: 

Research showed that resistance rates among Escherichia coli isolates to common antibiotics remained stable in emergency department (ED)-treated patients with community-acquired urinary tract infections (CA-UTIs), whereas prescribing shifted significantly from fluoroquinolones (52.3% to 9%) to beta-lactams (3.5% to 63.25%) between 2011 and 2021.

METHODOLOGY:

• Researchers conducted a retrospective study of two cohorts of adults with positive urine cultures who were treated and discharged from the ED without healthcare-associated risk factors for CA-UTIs. Patients with urine cultures specifically positive for E coli were analyzed separately as E coli subgroups.
• The 2011 cohort included 170 adults (mean age, 41 years; 5.9% men; 55.9% White; 5.9% with prior hospitalizations), and the 2021 cohort included 400 adults (mean age, 50 years; 12.5% men; 57% White; and 1.0% with prior hospitalizations).
• The primary outcome was trends in the susceptibility of urinary pathogens to commonly prescribed antimicrobial agents, including fluoroquinolones, beta-lactams, nitrofurantoin, and sulfamethoxazole-trimethoprim (SMZ/TMP), for UTI. Secondary outcomes focused on patients with E coli isolates and on shifts in empiric prescribing practices over 10 years.

TAKEAWAY:

• For all CA-UTI pathogens, resistance to levofloxacin remained stable (6.9% in 2011 vs 7.8% in 2021), whereas resistance to SMZ/TMP decreased slightly (22.0% vs 16.3%). Resistance to nitrofurantoin (18% vs 16.1%) and cefazolin (9.8% vs 7.1%) also decreased slightly, though not significantly.
• For E coli, resistance to levofloxacin (9.2% vs 9.9%) and SMZ/TMP (25.2 vs 26.6%) remained stable, whereas resistance to nitrofurantoin decreased significantly (8.4% vs 2.6%; P = .023).
• E coli was the predominant pathogen in CA-UTIs but its percentage declined significantly from 2011 to 2021 (75.7% to 56.8%; P = .000026), whereas infections involving Klebsiella and Proteus species increased, though not significantly.
• Prescription patterns shifted significantly from fluoroquinolones (52.3% in 2011 to 9.0% in 2021; P < .00001) and SMZ/TMP (22.9% to 6.8%; P < .00001) to beta-lactams (3.5% to 63.3%; P < .00001), whereas nitrofurantoin use reduced modestly (9.4 to 1.4%; P = .17) between 2011 and 2021.

IN PRACTICE:

"In ED-treated patients with CA-UTIs, resistance of urinary isolates to common antibiotic agents did not change significantly over a 10-year period. In the subgroup of patients with E coli, resistance to levofloxacin and SMZ/TMP remained unchanged, while resistance to NTF [nitrofurantoin] and cefazolin showed numerical improvement," the authors wrote. "Prescribing patterns changed significantly over the 10-year period, with a significant decrease in FQ [fluoroquinolones] and an increase in oral beta-lactam prescribing," they added.

SOURCE:

The study was led by Robin L. Southwood, College of Pharmacy, University of Georgia, Athens, Georgia. It was published online on August 29, 2025, in the American Journal of Emergency Medicine.

LIMITATIONS:

The study's retrospective design and single-center nature limited its generalizability. Patient follow-up was inadequate for evaluating clinical outcomes, and the 2011 cohort lacked statistical power for the E coli subgroup analysis. Additionally, resistance rates in the CA-UTI population were generally lower than in healthcare-associated UTIs, which may have affected the findings.

DISCLOSURES:

Funding information was not provided for the study. The authors reported having no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.