What Did We Find From Imaging Studies in Childhood Urinary Tract Infection and Which Studies Are Mandatory?

OBJECTIVE: To evaluate the imaging results of childhood urinary tract infection (UTI) in our setting, and examine if it would be appropriate to apply the recent guideline changes regarding imaging studies as routine practice in Thailand.

METHODS: Medical records of children with UTI aged 0-15 years were reviewed, with focus on renal ultrasound (RUS), cystogram, and 99m Tc dimercaptosuccinic acid (DMSA) renal scan results to determine congenital anomalies of the kidney and urinary tract (CAKUT) and renal damage. Mild CAKUT was defined as primary vesicoureteral reflux grades I-III or isolated hydronephrosis, and all other abnormalities were defined as severe CAKUT.

RESULTS: A total of 142 boys and 129 girls had at least 1 imaging study after UTI. Their median (interquartile range) age was 1.0 (0.5-2.7) year: 0.7 and 1.4 years for boys and girls, respectively (P = .006). A total of 262 children had an RUS performed, of which 99 (37.8%) were abnormal. Cystograms were performed in 221 children, from which 83 (37.6%) CAKUTs were detected, and 108 children had a DMSA performed, of which 53 (49.1%) were abnormal. Overall, CAKUTs were detected in 148 (54.6%) children, of which 43 were severe. RUS together with cystogram provided higher sensitivity (100% vs 88.9%) and specificity (53.8% vs 42.4%) to detect severe CAKUT than RUS together with DMSA.

CONCLUSION: A CAKUT was detected in more than half of the children with first UTI, with one-third having severe CAKUT. In our setting, RUS combined with cystogram is still the most reliable way to detect potentially harmful post-UTI problems, and the new western guidelines are not appropriate.