Hypercalcemia due to Graves' disease in a patient with thyroid hemiagenesis.

Thyroid hemiagenesis is a rare anomaly due to failure of development of one thyroid lobe during embryological life. A lot of thyroid disorders may accompany thyroid hemiagenesis. In this report, we present a case of thyroid hemiagenesis, who had moderate hypercalcemia due to Graves' disease. A 43-year-old woman presented with weight loss of more than 5 kg within one month, heat intolerance, and increased sweating. For the past month, she had been troubled by intermittent symptoms of vomiting, thirst, and constipation. On examination, she had tachycardia with no signs of dehydration. Pulse rate was 110 per minute. She had fine tremor, proximal muscle weakness, and asymmetric smooth goiter and hyperplasia in the right thyroid gland. Thyroid function tests confirmed the diagnosis of hyperthyroidism. Although hypercalcemia may be detected in patients with thyrotoxicosis, to the best of our knowledge, this is the first case report of thyroid hemiagenesis accompanying hypercalcemia due to thyrotoxicosis.