著明な情動不穏を認めたMarchiafava Bignami病の1例

A Case of Marchiafava Bignami Disease Presenting with Severe Dysphoria

【抄録】　Marchiafava Bignami病（MBD）の1例を報告する。本例では明らかな脳梁離断徴候を認めず，不機嫌・抑うつなどの精神症状を呈した。精神症状は発症後4か月から9か月まで持続し消退したが，症状が顕在化していた間，脳波の徐波化などが認められ，通過症候群に基づく症状と考えられた。本例の特徴は，経過が詳細に追跡できたことのほか，SPECTにおいて前頭・側頭部の血流低下を認め，精神症状の改善とともに正常化したことである。このことから，同部位の機能障害が本例の精神症状形成に関与している可能性が高いと思われた。また本例のMBD発症機転としては，重症アルコール性肝障害による代謝性の要因が関与している可能性があると考えられた。

　We report a patient of chronic alcoholism who presented with Marchiafava Bignami disease (MBD) after prolonged drinking.

　The patient showed no evidence of callosal disconnection symptoms. Instead, he showed psychiatric symptoms including severe dysphoria, irritability, agitation and depressive mood in the course of his recovery from an initial state of mild confusion.

　These psychiatric symptoms lasted for about six months, then gradually disappeared. While the psychiatric symptoms were obvious, transient slowness of background activities of the electroencephalogram and decrease in MMSE scores were noted, which suggested nonspecific “Durchgangssyndrom”. Interestingly, SPECT demonstrated transient hypoperfusion in the fronto-temporal areas, which normalized when psychiatric symptoms disappeared. We speculate that this transient fronto-temporal dysfunction may have contributed to the psychiatric symptoms.

　It is uncertain why this patient suffered from MBD, but lack of metabolic compensation for liver failure may have been crucial in causing MBD in this particular patient.