Lymphocytic Infundibuloneurohypophysitisの4例の報告

Report of Four Cases of Lymphocytic Infundibuloneurohypophysitis

I．はじめに

　下垂体部の慢性炎症性病変には，妊娠に関連して発症することが多く，下垂体前葉に限局した病変であるlymphocytic adenohypophysitisがある^3,4,6）．一方，尿崩症を主症状とし，下垂体茎から下垂体後葉を主座とする下垂体部の慢性炎症性病変が報告されており，これをlymphocytic in-fundibuloneurohypophysitisとしてKojimaらが最初に報告し^10），その後Imuraらが特発性尿崩症とされた症例の中に同様の病態を示す9例を認め，lymphocytic adenohypophysitisと区別すべく，一つの疾患群としてlymphocytic infundi-buloneurohypophysitisとすることを提唱した^9）．われわれも，MRIにて下垂体部から下垂体茎に及ぶ病変を認め，慢性の炎症性の病変により尿崩症を来たしたと思われた4症例を経験し，Imuraらが提唱したlymphocytic infundibuloneurohypo-physitisと同様の病態と思われ，この疾患の特徴などについて検討した．

We reported 4 cases of lymphocytic infundibuloneurohypophysitis. All four patients had diabetes insipi-dus as initial symptoms without anterior pituitary dysfunction. All patients showed pituitary stalk swellingand two patients showed enlargement of the pituitary gland. No patients were operated on for a histologic-al diagnosis. No patients received corticosteroid treatment for this pathology. The mean follow-up periodwas 36 months. The diabetes insipidus continued in all cases, but radiological findings showed improve-ment in all cases. In one case, adrenal insufficiency occurred after 10 months, but had disappeared 6months later.

We think lymphocytic infundibuloneurohypophysitis can be diagnosed without histological examinationsand can be treated conservatively without corticosteroid treatment. It seems to be a self-limiting disease.This disease can be distinguished from lymphocytic adenohypophysitis, but in some cases, both the ante-rior and posterior pituitary glands are invaded, and in this situation lymphocytic hypophysitis may be anappropriate name. Even if the initial symptom is diabetes insipidus, careful follow-up is needed for theduration of the disease.