Concomitant Graves' disease and primary hyperparathyroidism: the first case report in mainland of China and literature review.

Concurrent Graves' disease and primary hyperparathyroidism in the same patient is rare, probably accounts for hypercalcemia in no more than 1 percent of thyrotoxic patients. Hypercalcemia may be noted during the course of hyperthyroidism in as many as 22 percent of cases. The cause of hypercalcemia in a thyrotoxic patient might be due to the activation of osteoclastic bone resorption by the excess thyroid hormone, as the severity of hyperthyroidism correlates positively with osteoclastic activity in trabecular and cortical bone. In 1936, Noble JF et al reported the first case in the world. To our knowledge, only 49 such cases have been described in the literature until the year of 1989. No case has been reported again afterward. The occurrence of hypercalcemia in a patient with hyperthyroidism may present a challenging diagnostic problem. In this communication, we described the first case in mainland of China with hypercalcemia caused by concurrent hyperthyroidism and primary hyperparathyroidism, and the clinical and laboratory characteristics were studied before and after therapy with anti-thyroid medication.