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

Abstract

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 formers (40 men and 20 women). We analyzed the groups' excretion differences 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, hypocitraturia 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 more significant association (p<0.05) for recurrent stone formers (33.3%) compared to the first time stone formers (18.3%). Conclusions: Hypocitraturia was the most common lithogenic risk factor for stone patients. In the recurrent stone formers, a low urine volume is the risk factor that differentiates them from the first time stone formers. (Korean J Urol 2006;47:1093-1098) ꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏ