OBJECTIVE: To describe the prevalence of the most frequent etiological agents of community acquired urinary tract infection in children under the age of 15 years, as well as to analyse the antimicrobial susceptibility patterns of the most prevalent pathogen, Escherichia coli. METHODS: Retrospective study conducted from urine cultures of a single bacterial species, at a concentration > 10(5) colonies forming units/mL. The children included in the study were treated in the Pediatric Emergency Care Unit of the University Hospital of the University of Sao Paulo from January, 2006 to December, 2007. In order to analyze Escherichia coli antimicrobial susceptibility patterns, cases with recurrent urinary tract infection and/or carriers of uropathy were excluded. RESULTS: Among 176 urinary tract infection patients, 133 (76%) were females. Children less than two years old presented the highest prevalence of urinary tract infection (84 cases; 48%). E. coli was the main agent (122 cultures - 69% of the total). There were high rates of E. coli antimicrobial susceptibility to second and third-generation cephalosporins (cefuroxime and ceftriaxone, 100%), aminoglycosides (amikacin, 100%, gentamicin, 96.4%), nalidixic acid (97.3%), nitrofurantoin (98.2%) and quinolones (ciprofloxacin and norfloxacin, 98.2%); moderate susceptibility to first-generation cephalosporin (cephalothin, 78.4%); low susceptibility to ampicillin (38.7%) and sufamethoxazole-trimethoprim (55%). CONCLUSIONS: E. coli remains the most prevalent bacterial pathogen of community acquired urinary tract infection. Given the low in vitro susceptibility of these bacteria to sulfamethoxazole-trimethoprim and ampicillin, these drugs should not be elected as the initial choice for treatment.
urinary tract; Escherichia coli; child
