Causes and prevention of calcium-containing renal calculi.

Kidney stones are common, and recurrences are the rule. At least 90% of patients with kidney stones probably have some identifiable metabolic risk factor. Effective prophylaxis is often available, but with the relatively low rate of recurrence, compliance with the treatment may be a problem. Studies are required to determine the cost-effectiveness of metabolic investigation and prophylactic therapy versus the possible need for repeated treatment by means of extracorporeal lithotripsy, especially in patients having a first calcium oxalate stone.