尿閉をきたしたウイルス性髄膜脳炎の幼児例

Acute Urinary Retention Secondary to Aseptic Meningoencephalitis in an Infant : Case Report

はじめに

　Elsberg症候群は，成人領域では単純ヘルペス2型感染に併発する仙髄神経根炎による尿閉を呈する無菌性髄膜炎と定義されている。性器ヘルペスに罹患する患者の増加とともに症例数が増え注目され^1），非ヘルペス性の無菌性髄膜炎で尿閉を来す症例（広義）も報告されている。Elsberg症候群の中核症状は，無菌性髄膜炎に伴う急性の脊髄神経根障害とそれに随伴した一過性の括約筋障害で，感染が髄膜にとどまらず脳・脊髄実質に及んだことによる症状は，周辺症状と捉えられている^2）。小児の報告は少なく，小児科領域ではあまり知られていない。今回，何らかのウイルス感染による発熱の後，いったん解熱したころから，膀胱直腸障害，下肢筋力低下を呈した症例を経験したので若干の考察を加え報告する。

Abstract

　We report the case of a 21-month-old boy with urinary retention secondary to aseptic meningitis.　After high fever for 10 days, appetite loss, somnolence, acute transient urinary retention, constipation and mild dysesthesia in bilateral lower limbs developed.　Brisk reflexes were present in the lower extremities along with a positive Babinski reflex.　Cerebrospinal fluid (CSF) examination revealed mild mononuclear cell-dominant pleocytosis.　Human herpes virus (HHV)-6 was not detected in the CSF by polymerase chain reaction (PCR) analysis; however, it was detected in the throat, plasma, and mononuclear cells of the peripheral blood.　Virus-specific immunoglobulin M antibodies against HHV-6 were not detected by enzyme immunoassay.　Brain magnetic resonance imaging (MRI) yielded normal results; however, T1-weighted MRI of the conus terminalis with contrast enhancement showed region of high intensity from the lower thoracic to lumbar meninges.　In T2-weighted imaging, slight hyperintensity was observed in the lumbar spinal cord without enhancement effect.　The catheter was removed 1 week after high-dose intravenous methyl-prednisolone treatment and the patient was able to walk 3 weeks later without any sequelae.　Vesicorectal disturbance and the neurological symptoms observed in aseptic meningitis were similar to those of HSV type 2-induced lumbosacral meningo-radiculitis, designated as Elsberg syndrome or meningitis-retention syndrome in adults.　The recurrence of HHV-6 might be immunologically related to this meningitis-retention syndrome based on the results of PCR analysis and enzyme immunoassay for virus-specific antibodies.　Several reports have described lumbosacral meningo-radiculitis in adults and older children, but this appears to be particularly rare in infants.