Disseminated vasculomyelinopathy: an immune complex disease.

The numerous nervous system abnormalities which follow antecedent infections and immunization appear to share a common pathogenesis involving the immune system. Pathologically, a small vessel vasculopathy involving arterioles and capillaries as well as venules in both gray and white matter is the earliest and most consistent change. Perivascular demyelination appears to develop subsequently. Delayed hypersensitivity to myelin basic protein may not adequately account for these changes. Humoral immunity may be involved instead. I postulate that antigen-antibody complexes, formed following the introduction of foreign antigen by infection or inoculation, cause vascular injury with secondary damage to myelin. There is considerable evidence that circulating immune complexes are present in some postinfectious nervous system disorders, as are associated systemic features which suggest immune complex disease. Similar clinical and pathological nervous system changes occur in a variety of disorders in which circulating immune complexes are thought to cause vascular injury.