Decreasing susceptibility of bacteria to ampicillin/ sulbactam and third generation cephalosporins in urinary tract infections

BACKGROUND: Urinary tract infections (UTIs) are among the most common bacterial infections worldwide and have become more difficult to treat over the years. Inappropriate antibiotic use has led to increased antibiotic resistance. MATERIALS AND METHODS: We examined 1921 urine culture samples from a single hospital and analyzed them for bacterial spectrum and antibiotic susceptibility. We further analyzed changes in the rates of detected bacteria and of the sensitivity of these uropathogens to antibiotics over the years. RESULTS: In our hospital-based analysis, cystitis was the most frequently diagnosed UTI in women (76%) and men (79%). Escherichia coli (48%) was the most commonly identified uropathogen. Samples demonstrated an increase in the proportion of E. coli (p < 0.001) and a decrease in Enterococcus faecalis (p < 0.001) over the study time period. Antimicrobial susceptibility analysis showed an increase over time in the number of isolates with resistance to ampicillin/sulbactam (p < 0.001) and to third-generation cephalosporins cefotaxime (p = 0.043) and ceftazidime (p < 0.001). CONCLUSIONS: Ampicillin/sulbactam and third-generation cephalosporins are antibiotics frequently used in the treatment of UTIs. When selecting an optimal antimicrobial treatment regimen for patients with UTIs, it is imperative to understand regional and timedependent differences in the prevalence of various uropathogens and antimicrobial resistance patterns. Therefore, continuous surveillance of local pathogen and antimicrobial susceptibility patterns for frequently used antibiotics should be prioritized.