慢性B型肝炎の経過中血管炎と血中免疫複合体が高値を呈した慢性多発神経炎の1例

A CASE OF CHRONIC POLYNEUROPATHY ASSO CIATED WITH CHRONIC TYPE B HEPATITIS

　抄録　胃切除術後に輸血後B型肝炎を併発し，慢性肝炎の経過中10年後に多発神経炎をきたした31歳，男子例を報告した。肝生検で慢性肝炎の像を認め，皮膚・筋・神経生検で血管炎の像を認めた。腓腹神経有髄線維密度ヒストグラムでは大径線維が著明に脱落しており血管炎によるvasculomyelinopathyと考えられた。本例は血中免疫複合体が高値であり，従来より指摘されているHBs抗原からなる免疫複合体による肝外症状と同様，本例の多発神経炎は免疫複合体による血管炎が原因である可能性が考えられた。

A case of chronic polyneuropathy associated with chronic type B hepatitis was described.

A 31 year-old male was admitted to our hospital with a 2-year history of progressive weakness and sensory disturbances of all limbs. There was past history of acute type B post-transfusion hepatitis after subtotal gastrectomy. On examination there was generalized muscle weakness, particularly in movements of the hands and feet with areflexia. He had a steppage gait. Sensory examination revealed moderately decreased pinprick, light touch, vibration and position sense in the distal portion of all extremities. On admission, hepatitis associated antigen and antibody were negative and positive, respectively. The level of circulating immune complexes was high with the titer of 6. 6 fig/m/ by Clq assay and 16x by Raji cell assay. Liver biopsy revealed fibrosis and periportal in-flammatory infiltrate compatible with the diagnosis of chronic viral hepatitis. Sural nerve biopsy showed marked loss of large myelinated fibers and epineural vasculitis with the thickened blood vessel wall and mononuclear cell infiltrates. There have been increasing evidences that extrahepatic manifestations are caused by vasculitis due to HBs antigen-antibody immune complex deposits. On the basis of findings in the literature it seems possible that chronic polyneuropathy may be related to the vasculitis due to HBs antigen-anti-body complex deposits after hepatitis B virus infection.