AB087. Hashimoto’s thyroiditis: a cause for hypercalcaemia?

Background: Hypercalcaemia can be caused by many disorders. Primary hyperparathyroidism is the leading cause with parathyroidectomy being the definitive management. Familial hypocalciuric hypercalacaemia is a rarer cause in which resection of the parathyroid tissue does not result in normalised serum calcium.

Methods: We report the unusual case of a 53-year-old lady who presented with hypercalcaemia and primary hyperparathyroidism and was found to have concurrent familial hypocalciuric hypercalcaemia.

Results: The cause of this woman’s hypercalcaemia is unknown. Serum calcium completely resolved on surgical resection of the thyroid and parathyroid tissue, however histopathology revealed normal parathyroid glands and florid Hashimoto’s thyroiditis, raising the possibility of a link between the two.

Conclusions: Our case demonstrates the diagnostic dilemma in hypercalcaemia that may lead a patient to undergo unnecessary invasive procedures. This case raises the interesting possibility of a link between Hashimoto’s thyroiditis and parathyroid disease. Further studies in this area are required to ascertain the link between these two conditions.

Keywords: Familial hypocalciuric hypercalcaemia; Hashimoto’s thyroiditis; hypercalcaemia; hyperparahythroidism