低ナトリウム血症で発症したRathke's cleft cystの1例

Symptomatic Rathke's Cleft Cyst Presenting with Hyponatremia:a case report

I．はじめに

　近年，symptomatic Rathke's cleft cystの症例が多く報告されている．その症状のほとんどは下垂体機能低下に伴う症状，視野障害，頭痛である^8,12,13）．今回われわれは，低ナトリウム血症が中心となって発症した1例を経験したので報告する．

A case of symptomatic Rathke's cleft cyst, showing symptoms due to hyponatremia, is reported. The pa-tient was a 68-year-old woman with complaints of vomiting, diarrhea and somnolence. She had severe hyponatremia (109mEq/l). Magnetic resonance image showed a cystic mass in the intra- and suprasellar re-gion. A right fronto-temporal craniotomy was per-formed and the cyst was partially resected through the pterional approach. The cyst compressed the chiasma and anterior hypothalamus upward. In the cyst, there was xanthomatous fluid and hematoma. On histopatho-logical examination, the cyst epithelium was diagnosed as Rathke's cleft cyst with craniopharyngioma compo-nent. These findings suggested that rapid compression to the anterior hypothalamus by intracystic hemorrhage caused hyponatremia.