Comparison of spiral CT and US in the evaluation of pediatric urolithiasis.

The objective of the study was to determine the value of spiral computerized tomography (CT) in detecting urolithiasis in pediatric patients and compare its efficacy with ultrasound (US). Twenty-nine infants aged between 2 to 94 months with clinical presentation suggestive of urolithiasis and a negative or indeterminate plain film were included in the study. Abdominal US and spiral CT were performed in all patients. Presence, size and localization of stones were noted for each patient on both CT and US. The diagnosis of urolithiasis was confirmed by passage of stones spontaneously, extracorporeal shockwave lithotripsy (ESWL), surgery, or clinical follow-up. Presence of stones was confirmed in 23 of 29 patients (79%). Eight patients had single stone and the remaining 15 had multiple stones either in a single localization (single kidney or single ureter) or multiple localizations. Spiral CT detected 57 stones (45 renal and 12 ureteral). US detected 34 stones (59.6%) in 18 (78.2%) patients. US was able to localize 31 stones (68.8%) in 21 kidneys (75%), and 3 stones (25%) in 11 ureters (27.2%). Spiral CT is very effective in the diagnosis of pediatric urolithiasis. Spiral CT is more efficient than US in imaging pediatric patients with symptoms and signs of urolithiasis, when KUB is inconclusive.