Lymphocytic hypophysitis mimicking pituitary macroadenoma

Lymphocytic hypophysitis is an uncommon disease with a variable presentation and unclear pathophysiology. We present the case of a 30 year old woman who presented with features typical of a pituitary macroadenoma. She underwent a transphenoidal resection of the mass and histopathological examination revealed lymphocytic hypophysitis. This case illustrates the difficulty in differentiating pituitary macroadenoma and lymphocytic hypophysitis and the variable presentations of lymphocytic hypophysitis.