Hyperparathyroid crisis reviewed: a role for parenteral cimetidine?

Hyperparathyroid crisis secondary to primary hyperparathyroidism has variously been described as hypercalcemic crisis, parathyroid storm, and parathyroid intoxication as well as other equally descriptive terms. Whatever the nomenclature, all emphasize the seriousness and urgency of the condition. Although fewer than 200 cases have been described since the first report by Hanes in 1939, it is generally agreed that hyperparathyroid crisis is more prevalent than commonly appreciated. The signs and symptoms of the syndrome are believed due not only to the presence of hypercalcemia, but to the toxic effects of parathormone as well. Its wide, but nonspecific clinical spectrum makes it easily confused with other causes of rapidly fatal cardiovascular or renal disease. The mortality in untreated cases is essentially 100 per cent. With combined medical-surgical treatment, it is still reported as high as 60 per cent. Three patients with severe hyperparathyroid syndrome are reported. Effective control of both hypercalcemia and the toxic effects of acute hyperparathyroid crisis was achieved with the use of parenteral cimetidine. Definitive surgical removal of a solitary parathyroid adenoma was performed in all three patients. The intimate relationship of the bioavailability of cimetidine and its effect in primary hyperparathyroidism is clearly demonstrated. An analogy to the use of cimetidine in Zollinger-Ellison syndrome is made. Both are endocrinopathies that require doses of cimetidine in excess of that normally considered therapeutic for peptic ulcer disease. The signs and symptoms of hyperparathyroid crisis as well as current modalities of treatment are reviewed. It is concluded that parenteral cimetidine is an important aid in the management of acute hyperparathyroid syndromes secondary to primary hyperparathyroidism.

The preoperative use of cimetidine as a means of preventing symptomatic hypocalcemia following a parathyroid operation.

Cimetidine has been shown to lower circulating PTH levels effectively by causing an intraglandular rearrangement of PTH peptides in human parathyroid tissue in instances of primary hyperparathyroidism. A state of "euparathyroidism" is established. It has been statistically found at a 98.7 per cent confidence level that preoperative treatment with cimetidine effectively prevents symptomatic hypocalcemia postoperatively after parathyroid operations. It is anticipated that cimetidine has provided a tool for the in depth exploration of parathyroid disease.