The aetiological and clinical pattern of childhood urolithiasis in Saudi Arabia.

The clinical and aetiological pattern in 85 stone-forming children presenting to an integrated nephrourological service in Riyadh is reviewed. All patients were below the age of 15 years, the male to female ratio being 2:1. Only 2 children presented with bladder calculi. The remaining all had upper tract stones and, in 12 cases, these were bilateral. Of 34 calculi recovered for analysis, one-third was predominantly calcium oxalate and a further third was composed of uric acid or urate. Four patients had cysteine stones and the remaining 7 presented mixed calcium stones, 6 (17.6%) being struvite and infection-related. Of the 85 patients 55 were treated successfully with extracorporeal shock wave lithotripsy, 16 underwent surgery and 7 had their stones removed by endourological procedures. In the remaining 7 children, stones dissolved or were passed spontaneously during medical therapy. Nine children (10.6%) showed a primary metabolic defect leading to their stone formation, 10 (11.8%) had a predisposing anatomical anomaly and 15 (17.6%) presented with urinary tract infection. Of the remaining 51 patients (60%) with idiopathic disease, 6 showed hypercalciuria on investigation and 2 children may have formed their stones due to prolonged recumbency.

Failure of clinical and laboratory characteristics to differentiate mesangial proliferative from minimal-change nephrotic syndrome.

Twelve clinical and laboratory characteristics of nephrotic syndrome were compared in 24 children with biopsy-proven mesangial proliferative glomerulonephritis (MesPGN) and 17 children with biopsy-proven minimal-change nephropathy (MCNS). The objective of the study was to determine if these characteristics alone, without renal biopsy, could be used to differentiate the two histopathologic entities. Sex, urinary protein level and IgM immunofluorescence were found to be significantly different in the two groups. Discriminant analysis produced two formulae which gave a discriminant rate of 79% for MesPGN and 76% for MCNS. We conclude that the clinical and laboratory characteristics studied could not differentiate MesPGN from MCNS.