Evaluation of Ciprofloxacin Resistance in Escherichia Coli Isolated From Urine of Outpatients With and Without Chronic Kidney Disease

Urinary tract infections are among the most common bacterial infections in clinical practice, with Escherichia coli as the main etiologic agent. Increasing antimicrobial resistance, especially to fluoroquinolones, represents a significant challenge in empirical management of these infections. Patients with chronic kidney disease (CKD) are particularly susceptible to infections and have greater prior exposure to antimicrobials, hospitalizations and comorbidities, factors that may favor the selection of resistant strains. In this context, it is essential to evaluate ciprofloxacin resistance profiles in E. coli isolated from urine of outpatients, comparing individuals with and without CKD, to guide appropriate therapy and contribute to bacterial resistance control strategies. Cross-sectional study conducted through data collection from urine cultures of patients referred to a teaching hospital located in the Zona da Mata region of Minas Gerais. Urine culture results from 2024 were collected, and parameters analyzed included sex, age, microorganism isolated, resistance to ciprofloxacin and outpatient clinic of origin, which was divided into CKD clinic and general clinic (other medical specialties). This study was approved by the institutional research ethics committee. In 2024, 1,958 urine samples were submitted for culture, of which 21.4% (n=419) were positive for a microorganism, 10.3% (n=202) were considered mixed cultures and 68.3% (n=1,337) were negative. Among positive cultures, 78.8% were from female patients, and mean age was 56.3 years. E. coli was isolated in 48.4% (n=203), of which 25.12% (n=51) were resistant to ciprofloxacin. In the CKD clinic, 104 urine cultures were positive for bacteria; E. coli was isolated in 55.8% (n=58), and 44.8% (n=26) of these were resistant to ciprofloxacin. In the general clinic, among 315 positive cultures, E. coli accounted for 46% (n=145), of which 17.24% (n=25) were ciprofloxacin-resistant. The data show a significantly higher rate of ciprofloxacin resistance in Escherichia coli isolated from patients with chronic kidney disease compared with patients from the general outpatient clinic. This finding reinforces the need for continuous surveillance of susceptibility profiles, especially in high-risk populations.