Childhood urolithiasis in Iran with special reference to staghorn calculi.

Between 1972 and 1984 148 children with urolithiasis were studied and managed at the University Clinic Children's Hospital of Teheran. In 125 children the calculi were in the upper and in 23 children in the lower urinary tract. The maximum incidence was between the ages of 5-8 and 12 years. 25 children had malformations and 16 had metabolic disorders. Cystinuria was observed in 6 and xanthinuria in 3 cases. The main constituents of calculi analyses in the upper urinary tract were calcium oxalate followed by ammonium acid urate. In the lower urinary tract ammonium acid urate and oxalate were seen with equal frequency, followed by uric acid. 16 children had staghorn calculi with an age profile of 5-13 years. Predominant symptoms were flank pain and gross hematuria. In 4 cases the calculi were bilateral. The calculi were removed successfully by pyelotomy and extensive pyelolithotomy. In 2 cases with more branched-out staghorn calculi and separate fragments, a logitudinal extensive nephrotomy was performed. In the absence of recurrent stones, renal growth and function were satisfactory postoperatively. In the majority of the cases the analyses of the staghorn calculi revealed phosphate.