[Lymphocytic hypophysitis: a report of 3 cases].

OBJECTIVE: Lymphocytic hypophysitis is a rare inflammatory lesion of pituitary gland. To enhance the knowledge of lymphocytic hypophysitis, herein we reported 3 cases of lymphocytic hypophysitis and reviewed the literature. METHODS: The clinical data of 3 patients diagnosed as having lymphocytic hypophysitis were analysed. RESULTS: All the three patients were young females, one of them (case 1) was affected in the postpartum period, however, the others were neither pregnant nor in postpartum period. Clinically, the most frequently seen symptoms and signs were attributable to pituitary hypofunction, headache and diabetes insipidus. Pituitary MRI revealed enhanced mass with pituitary stalk enlargement expanding the pituitary fossa, extending into suprasellar area and compressing optic chiasm. Typically the lesion appeared hypointense or isointense on T1-weighted imaging, but hyperintense on T2-weighted imaging. Histopathological examination showed extensive destruction of anterior acini of the pituitary with a dense infiltration of lymphocytes, plasma cells, histocytes and other inflammatory cells. Two patients (case 2 and 3) were successfully treated for mass reduction of pituitary gland and restoration of pituitary function with high dose methylprednisolone pulse therapy (HDMPT). CONCLUSIONS: Lymphocytic hypophysitis is a rare autoimmune endocrinopathy which can affect young woman in the postpartum period, or in the peripartum period, characterized by focal or extensive lymphocytic infiltration of anterior pituitary acini. It may cause pituitary expansion and a varying degree of hypopituitarism mimicking the features observed in pituitary adenoma. HDMPT was proved to be effective for mass reduction of pituitary gland and restoration of pituitary function.