Comparison of the clinical and laboratory characteristics of infants and children with urinary tract infection caused by E. coli (n = 107) or other pathogens (n = 32) yielded a significantly higher association of non-E. coli disease with urinary tract anomalies, younger age, and previous antibiotic treatment. Underlying urinary tract anomalies were noted in 18 patients, of whom 14 (77%) were infected by non-E. coli pathogens. The most frequent anomaly was grade 3-4 vesicoureteral reflux (50%), followed by hydronephrosis (22.7%), ureteropelvic junction obstruction (9%), hypospadias (4.5%), pinpoint meatus (4.5%), and dysplastic kidney (4.5%).