Cefixime-Clavulanic Acid in ESBL-Producing E. coli Lower Urinary Tract Infections: A 13-Patient Case Series

Background: Urinary tract infections (UTIs) represent a substantial proportion of community-acquired infections. The increasing prevalence of Escherichia coli strains that produce extended spectrum beta-lactamases (ESBL) poses a significant obstacle to effective infection treatment. Although carbapenems are effective against ESBL-producing isolates, their broad-spectrum activity, potential for collateral damage, high cost, need for intravenous/intramuscular administration, and hospitalization limit their use, particularly for lower UTIs in outpatient settings. Therefore, there is a growing need for effective oral alternatives. Methods: This retrospective study evaluated the clinical and microbiological outcomes of 13 patients diagnosed with lower UTIs caused by ESBL-producing E. coli (ESBL-PE), treated with oral cefixime-clavulanic acid (400/125 mg every 12 hours for 14 days). Follow-up urine cultures were obtained on days 3–5 and/or at the end of treatment (days 11–14). Results: On days 3–5 of treatment, microbiological and clinical success rates were 53.8% (7/13) and 61.5% (8/13) respectively. At the end of the treatment, urine culture results could be evaluated in 10 cases, microbiological success was 80% (8/10). Clinical success was 84.6% (11/13). Re-infection and relapse rates on day 30 post-treatment were 7.7% (1/13) and 30.8% (4/13), respectively. Conclusions: Cefixime-clavulanic acid may be considered an alternative to older antibiotics such as fosfomycin and nitrofurantoin in the treatment of uncomplicated urinary tract infections, and may also contribute to the prevention of carbapenem resistance development.