Subacute thyroiditis presenting as Cushing's syndrome. Case report.

Subacute thyroiditis is a benign, self-limited disorder characterized by hyperthyroidism that resolves spontaneously. Although cortisol metabolism is accelerated in hyperthyroidism, cortisol levels are usually normal. We describe a child with subacute thyroiditis whose presenting complaints and preliminary evaluation suggested a diagnosis of Cushing's syndrome. There was spontaneous improvement in the signs and symptoms with concomitant normalization of laboratory values. We conclude that hypercortisolism may be a manifestation of hyperthyroidism, and the evaluation of Cushing's syndrome should include thyroid function tests.