Comparison of the Lithogenic Risk Factors for First Time and Recurrent Stone-formers

Purpose: The lithogenic risk factors were compared between the first time stone patients and recurrent stone patients according to age and gender. Materials and Methods: We performed stone metabolic studies on first time stone formers (67 men and 42 women) and the recurrent stone for-mers (40 men and 20 women). We analyzed the groups ' excretion differ-ences for the lithogenic and inhibitory constituents such as calcium, uric acid, oxalate, sodium and citrate; we measured volume from the 24-hour urine samples and calcium, uric acid, sodium, potassium, chloride and phosphate from the serum samples. Hypercalciuria, hyperoxaluria, hypo-citraturia and a low 24-hour urine volume (＜1,500ml) were compared between the two groups according to age and gender. Results: Hypocitraturia was the most common metabolic abnormality in all the groups. The incidence of hypocitraturia was higher in the recurrent stone formers (50.0%) than in the first time stone formers (48.6%), but this was not statistically significant. A low urine volume was shown to have