Etiologic and Epidemiologic Pattern of Urolithiasis in North Iran;Review of 10-Year Findings

Objective: To determine epidemiologic and metabolic characteristics of renal stone in the northern Iran. Methods: We prospectively analyzed demographic, clinical and metabolic findings in children less than 16 years old with renal stone revealed by ultrasonography from September 2003 to May 2012. Evaluations included serum and urine measurement of main elements predisposing patients to stone formation. Findings : 271 children (160 males) aged 2 months to 16-years (mean 30 months) were evaluated. 91 (33.6%) had a positive family history, abdominal discomfort (18.8%), UTI (11.8%) and hematuria (11.4%) were main presenting features. 45 children were diagnosed accidentally without any specific compliant. Nearly all (99%) stones lay in kidney., 35.1% had metabolic, 10% infective and 4.1% obstructive trends, 110 children had no definable etiology. Hypercalciuria (25.5%) hyperoxaluria (18.4%) and hypocitraturia (18.1%) were more frequent than uricosuria (8.5%) and cystinuria (3.1%) Conclusion: Metabolic derangement plays significant role in stone formation in our area. Patients should be carefully evaluated considering this point of view.Key Words: Nephrolithiasis, Kidney Stone, Hypercalciuria, Hyperoxaluria, Cystinuria, Hypocitraturia