Xanthomatous hypophysitis: A rare case report with review of literature.

Hypophysitis is classified into primary and secondary. Xanthomatous hypophysitis is one of the rare types of primary hypophysitis. A 55-year-old female presented with headache, vomiting, and blurring of vision. She also had endocrine dysfunction in the form of low serum T3, T4, and low cortisol levels. MRI scan showed a sellar expansile lesion suggestive of pituitary macroadenoma. Microscopy showed pituitary tissue replaced by inflammatory infiltrate made up of foamy histiocytes arranged in sheets along with lymphoplasmacytic infiltrate. Interspersed areas of fibrosis, hyalinization, few congested and sclerosed blood vessels were seen. Compressed residual pituitary tissue was identified at the periphery. Xanthomatous hypophysitis is a rare entity which can mimic as pituitary adenoma both clinically and radiologically. Accurate diagnosis at an early stage with postsurgical steroid therapy may help to prevent permanent pituitary damage.