The natural history of calcium urolithiasis

The course of untreated calcium renal stones, derived from the retrospective study of 300 patients with defined metabolic disorders and from the analysis of two prospective, published studies, is complex and heterogeneous. Generally, stones provoke considerable morbidity; hyperuricosuria is associated with an unusually severe stone disease. Stone recurrence rates usually remain stable, or rise with successive stones; in a minority of patients, the reverse is true. A single stone is likely to be followed by a recurrence. The mean time to recurrence averages 6.78 years, with peaks at 1.56 and eight years. Because the disease is likely to be morbid and chronic and does not wane with age, diagnostic evaluation and treatment should be strongly considered for any patient with recurrent stones, and for those in whom recurrence is likely to pose more than the usual risk. (JAMA238:1519-1523, 1977)