Primary hyperparathyroidism is known to coexist with thyroid cancer and breast cancer. However, primary hyperparathyroidism coexisting with Graves disease is extremely rare. The aim was to describe the case of a patient with Graves disease causing severe hyperthyroidism who in the course of the disease developed vitamin D deficiency and primary hyperparathyroidism. A patient, female, aged 49 years, presented with severe hyperthyroidism causing tachycardia, palpitations and weight loss. TSH receptor antibodies were positive in the context of Graves disease. She was treated with methimazole and propranolol and the disease went into remission. A year later treatment with methimazole was discontinued and 4 months later the patient had a relapse of hyperthyroidism. Laboratory tests revealed hyperthyroidism along with vitamin D deficiency and elevated PTH levels. Vitamin D was administered along with methimazole and propranolol. During follow up, despite normal vitamin D levels, PTH levels remained extremely elevated and blood calcium levels in the upper normal range. Ultrasound of the thyroid and parathyroid glands revealed a parathyroid adenoma adjacent to the left thyroid lobe. The adenoma was visible in a scan with 99mTc-sestamibi. The patient is being followed up and prepared for surgical treatment of both hyperthyroidism and primary hyperparathyroidism. The extremely rare case of a patient with concurrent Graves disease causing severe hyperthyroidism and primary hyperparathyroidism along with vitamin D deficiency is presented. This case further illustrates that primary hyperparathyroidism may be diagnosed in the context of severe vitamin D deficiency, being aggravated by vitamin D administration and that primary hyperparathyroidism may coexist with thyroid disorders.
20 - 23 May 2017
European Society of Endocrinology