ヘルペス脳炎の再発と遷延

Recurrence and protraction of herpes simplex encephalitis

　単純ヘルペス脳炎（herpes simplex encephalitis：HSE）は非流行性脳炎の中では頻度が高く，急性ないし亜急性の発症で側頭葉を中心にした病変を認め，意識障害と神経局在徴候を呈する。通常は単相性の経過をとるが，時に再発例や慢性例が報告されている。ここではHSEの非典型例の臨床的特徴を明らかにするため，HSEと診断された27人の連続症例の臨床症状，髄液を含む検査所見，臨床経過，治療や予後などについて検討した。その結果，再発のエピソードを有する6例と慢性経過を示す3例が認められた。病型や症状は様々で，PCRによる髄液中のウイルスDNA検索は診断に有用であった。また，再発例や慢性経過例に対する抗ウイルス薬の反応は良好であった。

　Herpes simplex encephalitis（HSE）frequent in non-epidemic encephalitis cause acute or subacute disorders of the central nervous system（CNS）with consciousness disturbance and focal neurological deficit dominantly in limbic system and temporal lobe. Its clinical course is typically monophasic but recurrent or chronic cases are sometimes reported. To clarify clinical features of atypical form of HSE, 27 consecutive patients with HSE were retrospectively analysed with respect to clinical symptom, laboratory findings including cerebrospinal fluid（CSF）, clinical course, treatment and prognosis. As a result, 6 patients with HSE having a recurrent episode and 3 patients with chronic or prolonged course of HSE were observed. The disease form and the symptoms of these patients were various. Detection of viral DNA in CSF by polymerase chain reaction was useful in a diagnosis of atypical form of HSE. In addition, the response of antiviral agent for recurrent and chronic cases was satisfactory.