005 A case of xanthomatous hypophysitis presenting as recurrent pituitary adenoma

Xanthomatous hypophysitis is a rare inflammatory disorder of the pituitary gland which can present as a recurrent pituitary adenoma. We present a case of 58 year old lady initially presented over two decades ago with symptoms of pan- hypopituitarism with extreme lethargy. She has a background history of bacterial meningitis aged 30. MRI brain for the hypopituitarism showed a pituitary adenoma. As she had deterioration in the visual acuity a resection surgery of the presumed pituitary adenoma was done which improved her vision. Histopathology, however did not show features of adenoma but showed cellular infiltrates representing macrophages, admixed with small amount of plasma cells and foamy histocytes, a few B-cells and small number of IgG4 cells. The IgG4-cells were insufficient to make a diagnosis of IgG4 disease. Over the next year, her vision deteriorated requiring a re-do pituitary debridement again showing foamy macrophages and necrosis with a positive CD68 immunohistochemistry this raised a possibility of xan- thomatous hypophysitis or necrotising hypophysitis. She had further visual deterioration over the next 6 months for which she was given a course of IVMP which improved her vision significantly without a need for surgery. A follow up MRI with contrast showed reduction in the size of the lesion with no relapse.