頭蓋底の巨細胞腫様病変の1例

HISTOPATHOLOGICAL FINDINGS OF A GIANT CELL TUMOR THAT INVADED THE SKULL BASE CAUSED BY PROLONGED HEMODIALYSIS

　I．はじめに

　腎臓の疾患と聴器とは，まつたく解剖学的にはかけはなれた器官であり，関係がないように思われる。しかし機能的に考えると内耳とくに内リンパ液の高カリウム，低ナトリウムの液を産生する機構が，腎における糸球体，尿細管の機能と非常に似ている。また，著者ら^1）もすでに腎と中耳の奇形を伴つた症例を報告した。これは中耳は第1，第2鰓弓より分化し，腎，生殖器は，前腎，中腎，後腎より分化するといつた発生学的にも似た点がある。またAlport^2）症候群のごとく，腎疾患と聴覚障害は遺伝性の疾患ばかりでなく，アミノ配糖体系の腎，聴器に対する毒性をふくめて，いくつかの類似性も強調できる。また頭蓋における巨細胞腫は少なく，とくに側頭骨には著者ら^3）の報告を含めて非常に稀である。今回著者らは，人工透析治療中に内耳にははつきりした障害はおこさなかつたが，側頭骨，鼻・副鼻腔の骨に異常をきたし，また全身のカルシウム代謝に異常をおこして死亡し，その側頭骨，前頭蓋に巨細胞腫のごとぎ像をしめした一症例を剖検できたので，その結果を報告し，あわせて考按をくわえたので諸家のご批判を仰ぎたい。

　A woman, aged 31, died from the attack of hyperpotascaemia after a prolonged period of hemodialysis. The patient suffered from osteofibrosis generalis renalis caused by secondary hyperparathyroidism which was present during the final 2 year.

　Decalcification of all bones was the most remarkable findings of this patient with formation of osteoclasts in all bones including the bones of the skullbase ; it resembled a giant cell tumor.

　The nasal septum showed hypertrophic swelling with decalcification and osteoclast formation. These structures were replaced by fibrous tissue with findings of giant cell even in submucouslayers. In the temporal bones, the most of the mastoid cells were replaced by fibrous tissue. But, in the perichondral and enchondral layers of the otic capsule very few of these changes were found.

　There were no remarkable pathological findings in the stria vascularis, hair cells, tectoral membrane nor the spiral ganglion cells.

　The audiogram taken a year before the patient's death showed a slight conductive hearing impairement which was remarkable in concordance with the histopathological findings of the temporal bones.