Hyperparathyroidism in thyrotoxicosis.

The frequency of hypercalcemia in 295 patients treated for thyrotoxicosis was 2 per cent. The combination of thyrotoxicosis and hyperparathyroidism is rare and only twenty-seven well documented cases could be found in the literature. Among ninety-two patients operated on for hyperparathyroidism, ten of them had thyrotoxicosis. In the present study, data on thirty-seven patients are reported. Hypercalcemia was found in all the patients and four of them had acute hyperparathyroidism. Hypophosphatemia was recorded in 60 per cent and hypercalcuria in 75 per cent of the patients. In ten patients there were renal concretions. Skeletal roentgenograms showed abnormalities in 65 per cent of the patients. In no instance had hyperparathyroidism commenced before thyrotoxicosis. Other recent reports on the etiology of hyperparathyroidism are discussed and it is concluded that hyperparathyroidism in thyrotoxicosis is a secondary disease. If a thyrotoxic patient with hypercalcemia still has elevated calcium values when becoming euthyroid after thyrostatic treatment, an operation should be performed. Because of a high recurrence rate in such patients with adequate follow-up, "near total parathyroidectomy" is recommended.