Clinical patterns of paediatric urolithiasis.

A series of 270 paediatric stone patients was studied retrospectively according to the clinical pattern of urolithiasis (age and sex, stone location, stone analysis, recurrence rate) and aetiology of stone disease (infection, anatomical, metabolic or idiopathic). Infection stones occurred earliest and more commonly in males and were usually upper tract struvite calculi related to Proteus infection. Anatomical stones were most commonly associated with pelviureteric junction (PUJ) obstruction and had a high recurrence rate, despite surgical correction of obstruction. Idiopathic stones most resembled those found in adult urolithiasis by virtue of occurring latest, being sited in the ureter more often and being more frequently composed of calcium oxalate. Metabolic stones were most frequently calcium phosphate or cystine and virtually all were renal. They comprised the smallest group but had the highest recurrence rate.