The metabolic evaluation of patients with recurrent nephrolithiasis: a review of comprehensive and simplified approaches.

The advent of percutaneous nephrostolithotomy and extracorporeal shock wave lithotripsy has definitely altered the way in which symptomatic renal calculi are approached. However, these new techniques should not affect the need for appropriate diagnostic evaluation and institution of medical treatment for the prevention of recurrent nephrolithiasis. A diagnostic evaluation should identify underlying physiological and environmental defects responsible for stone formation, as well as identify specific medical disorders that cause recurrent stone formation. With this information one then can construct an appropriate treatment program that will prevent the occurrence of additional calculi. Comprehensive metabolic protocols have evolved from tedious inpatient procedures to more convenient outpatient tests that can be performed in approximately 2 weeks. In addition, the advent of automated urinalysis packages has allowed many physicians access to reliable, sophisticated technology. Further dissemination of these simplified metabolic protocols will enable more accurate diagnosis of recurrent stone disease and, hopefully, permit the institution of appropriate medical therapy by a wider group of treating physicians.