Primary Granulomatous Hypophysitis Presenting with Secondary Hypothyroidism

ABSTRACT Objective We present a case of a 45-year-old woman with history of Graves disease treated with thyroidectomy who developed panhypopituitarism due to granulomatous hypophysitis. Methods The details of the case presentation, evaluation, diagnosis, and treatment are reviewed. On routine follow-up visits for thyroid condition, the patient complained of symptoms of hyperthyroidism, despite being on a previously adequate dose of levothyroxine. Work-up led to the diagnosis of hypophysitis. Results The patient responded to corticosteroid therapy, but 5 months later, magnetic resonance imaging of the brain showed recurrence of the disease. Eventually, the patient underwent partial transsphenoidal hypophysectomy, later developed recurrence of disease, and had total hypophysectomy. The postoperative pathology report was consistent of granulomatous hypophysitis. Conclusion Granulomatous hypophysitis is an uncommon inflammatory disease affecting the pituitary. It is commonly misdiagnosed as a macroadenoma because of its clinical presentation.