BERKELEY, CA (UroToday Inc.) - Febrile urinary tract infections (UTIs) affect an estimated 1.0% of boys and 3.1% of girls and cause significant morbidity. Anatomic obstruction (posterior urethral valves, ureteropelvic junction obstruction, ureterovesical obstruction, and ureterocele) as etiologies for UTI are seen in 2-10% of children while another 30-50% will have vesicoureteral reflux (VUR). The natural history of children who initially present with a febrile UTI and have no identifiable anatomic abnormality detected radiographically remains undefined.

The purpose of a study presented by G.C. Mingin et al, from San Francisco, was to determine the recurrence rate of febrile UTIs in children who had a negative radiologic evaluation at initial presentation and to identify the risk factors for UTI recurrence. The results were reported in the March, 2004 issue of Urology.

A retrospective review of 850 children who presented with a febrile UTI was performed. Seventy-eight children were found to have a negative radiologic evaluation (defined as the absence of hydronephrosis with normal renal parenchyma on ultrasound, as well as the absence of VUR on voiding cystourethrography). Of the 78 children, 25 were found to have a recurrent febrile UTI (3 boys and 22 girls). Forty-five percent of the girls recurred while 14% (3 of 21) of the boys had a recurrent febrile UTI. Mean follow-up was 3.5 years.

Of the 13 boys who were younger than one year of age at the time of their initial febrile UTI, 12 (92%) were uncircumcised. Of the seven boys aged 2 to 5 years, six were uncircumcised at the time of their initial infection. Of the three boys who recurred, all were uncircumcised. In girls, the age at the time of initial infection was not predictive of recurrence. It did appear that UTIs in girls aged five years and older were more often associated with dysfunctional elimination syndrome.

The results of this study suggest that in children who present with a febrile UTI and have a normal radiologic evaluation, recurrence is more common in girls. Uncircumcised boys also tend to have a greater risk of infection in the first year of life. Recurrence in girls older than age 5 was associated with a high rate of dysfunctional elimination syndrome.

Urology. 2004;63:562-565