Necrotizing Granulomatous Hypophysitis Presenting as a Sellar Mass

Abstract

We report the case of a 45-year-old Colombian female with a 3-month history of headache, anorexia, fatigue, and diplopia in addition to left facial nerve palsy 2weeks prior to presentation. On examination, visual fields and fundi were normal, but left abducens and facial nerve palsies were noted. An MRI scan disclosed a sellar mass with suprasellar but neither parasellar nor retrosellar extension. The mass was interpreted as a pituitary tumor and resected via the transsphenoidal approach. Histologic examination revealed necrotizing granulomas in a background of normal pituitary gland tissue. The differential diagnosis includes tuberculosis, sarcoidosis, fungal infection, syphilis, granulomatous autoimmune hypophysitis, Langerhans cell histiocytosis, and Erdheim-Chester disease. Staining for tubercle bacilli (acid fast and fite) as well as for fungi (GMS) was negative and PCR for mycobacteria showed the same result. Postoperative empiric treatment with antituberculous medication resulted in resolution of the cranial nerve palsies within a 1month. The diagnosis of inflammatory/infectious granulomatous hypophysitis can be difficult to diagnose preoperatively and occasionally even postoperatively. A high index of suspicion should be maintained especially in those patients with a history of a systemic granulomatous disease or in regions endemic in granulomatous infectious diseases.