脳肺吸虫症新鮮例のCT所見

CT Findings in “Fresh” Cerebral Paragonimiasis

I．はじめに

　食生活の変化と衛生状態の改善により，日本における脳肺吸虫症（Cerebral paragonimiasis）の発生はまれとなり，過去の疾患として忘れ去られつつある^3,9,14,23）．しかし国際交流が盛んになるにつれ，風土病あるいは地域特有の疾病が非汚染地域でも発生する可能性があり，また感染後20-30年経過した患者を診療することもあり，本疾患を鑑別診断の一つに入れておく必要がある^14）．

　中華人民共和国・東北地方においても，脳肺吸虫症は激減してきたが，われわれは1984年6月から1986年5月までの2年間に，脳肺吸虫症の新鮮例4例をCTスキャンで検索する機会を得，うち3例に対して手術を行った．

　新鮮例脳肺吸虫症のCT所見の報告は少ない^9）．われわれは宇高^23），木下^13）らが報告した陳旧性脳肺吸虫症のCT所見とわれわれが経験した新鮮例のそれとを比較し，その特徴につき検討した．

　また，脳肺吸虫症の臨床分類—病理所見—CT所見の関係，他の脳寄生虫症のCT所見と比較検討したので報告する．

There are few reports on cr findings in “fresh” cere-bral paragonimiasis. We have experienced four cases of “fresh” cerebral paragonimiasis examined by C'I“ scan. Three patients were children aged 7, 9, and 14 years, and one was an adult aged 25 years. Three patients were examined by CT scan 2 to 6 months after the onset of high grade fever, convulsion and focal deficit signs, and a patient was examined one month after his progressive visual disturbance.

The unique CT findings are multilocular cystic le-sions in temporo-occipital or in temporo-parietal lobes with extensive brain edema. Two cases were also associated with ”soap-bubble" calcifications. The cysts were more dense than CSF and enhanced by contrast media. The histopathological specimen showed that the eggs of paragonimus were in the abscess cavity, of which the wall was composed with highly vasculargliomesenchymal capsule and numerous cell infiltration. Three patients underwent craniotomy for removal of abscess and decompression. Bitionol were administered and all patients recovered well. We also discussed the differential diagnosis of cerebral parasitic granulomas.