Primary hyperparathyroidism: is there an increased prevalence of renal stone disease?

OBJECTIVE: Parathyroid adenomas cause hypercalcemia and are culprits in the development of renal stone disease. With serum assays available, early detection of parathyroid tumors is possible. We performed this retrospective review to determine whether the prevalence of nephrocalcinosis and nephrolithiasis is still increased in patients with primary hyperparathyroidism compared with those not affected by the disorder in view of the early detection of parathyroid adenomas.
MATERIALS AND METHODS: We retrospectively reviewed the renal sonograms of 271 patients with surgically proven primary hyperparathyroidism. All patients had undergone renal imaging within 6 months before parathyroid surgery. Our control group consisted of 500 age-matched subjects who had right upper quadrant sonograms obtained for various reasons.
RESULTS: Nineteen (7.0%) of the 271 patients with primary hyperparathyroidism had renal stones, and eight (1.6%) of the 500 subjects in the control group had stones. Pearson's chi-square analysis showed that this difference in prevalence is significant (p < 0.0001).
CONCLUSION: Our results showed a fourfold increased prevalence of asymptomatic renal stone disease in patients with surgically proven primary hyperparathyroidism compared with subjects not affected by the disorder. The National Institutes of Health consensus conference on asymptomatic primary hyperparathyroidism recommended that patients with renal stone disease undergo parathyroid surgery. These patients should undergo surgery even if they have minimal or no elevation of the total serum calcium value and no other metabolic manifestations of hyperparathyroidism. The finding of nephrocalcinosis or nephrolithiasis is, therefore, a significant finding in evaluating patients for parathyroid surgery. Routine imaging of the kidneys is necessary when primary hyperparathyroidism is documented.