The effect of parathyroidectomy on the recurrence of nephrolithiasis

Little information is available on the long-term influence of parathyroidectomy on the rate of renal stone formation in patients with primary hyperparathyroidism (pHPT) and nephrolithiasis. The reported occurrence of renal stone disease in untreated patients with pHPT is 15% to 30%. A registry of 258 pHPT patients who underwent parathyroidectomies at the Milwaukee Regional Medical Center has allowed continued follow-up of the 71 (28%) pHPT patients with associated renal stone disease. Patients have been followed up for an average of 5 years (range, 1 to 15 years) since surgery. The rate of renal stone formation before and after parathyroidectomy was compared. Identification of a "new" renal stone was defined as passage and collection, extraction, or radiographic visualization of stones. All 71 pHPT patients with stone disease had hypercalcemia and inappropriately elevated parathyroid hormone concentrations, and after parathyroidectomy these values returned to normal in 69 of 71 patients. Since undergoing parathyroidectomy, only 4 patients have passed renal stones. The rate of stone formation per patient per year was 0.36 before and 0.02 after surgery (p less than 0.001). Surgical correction of pHPT significantly reduced the rate of stone formation.