中枢神経系histoplasmomaの1剖検例

An Autopsy Case with Cerebral Histoplasmoma：Case Report

　要旨　中枢神経系ヒストプラズマ症は，日常診療において遭遇する機会の少ない稀な疾患である。播種型ヒストプラズマ症の10～50％に存在し，適切な診断により治療が可能な疾患であるが，しばしば致命的となり剖検で診断される場合もある。この度われわれは遺伝子解析にて確定診断に至った，中枢神経系histoplasmomaの剖検例を経験した。患者は土木関係企業に勤務し，アフリカ・中米を中心に渡航歴のある44歳の男性。後頭部痛にて発症し，頭蓋内に多発性の結節性病変を認めた。悪性リンパ腫を念頭に生検術を行ったが，診断に至らず不幸な転機をたどった。本症の診断には，その疫学的特徴より出生地，職歴，旅行歴および既往歴の聴取と，病理医との密接な情報交換が重要となる。本例の問題点および本疾患の疫学的・臨床的・病理学的特徴を，過去の報告と併せて検討する。

　Histoplasma capsulatum infection is, for the most part, asymptomatic or of little clinical consequence. Disseminated infection due to H. capsulatum is rather uncommon. Clinically apparent infection of central nervous system（CNS）is rare, and involves in 10 to 50% of patients with disseminated histoplasmosis. Although CNS histoplasmosis is frequently fetal or only discovered as an autopsy, some patients can be effectively treated with anti-fungal agents. We describe a 44-year-old civil man who is engineering contractor with headache without evidence of systemic infection. Magnetic resonance imaging showed enhancing masses in the third and forth ventricles, right interpeduncular cistern, and right cerebello-pontine angle. After biopsy of what was presumed to be a malignant lymphoma, the patient died of rapidly progressive multiple cerebral infarctions. The autopsy revealed the CNS histoplasmoma disseminating systemically. And we finally diagnosed him as histoplasmoma by gene analysis. It was extremely difficult to make a diagnosis based on his physical and radiological findings because it should be included in the differential diagnosis of a well or ring enhanced lesion. It is very important to ask patients about their birthplace, past illness, occupation, and where they had traveled. In the present case, the patient working for the construction has visited many countries including the African Continent and Central America. Clinicians should maintain a high index of suspicion in patients who are from any area endemic for histoplasmosis. The clinical, radiological and pathological features of this infection were reviewed in this report.

（Received : June 3, 2004）