Antineuronal antibodies in acute cerebellar ataxia following Epstein-Barr virus infection

A 29-year-old man developed acute cerebellar ataxia following Epstein-Barr virus infection. Serum IgG and IgM antibodies reacted with both nuclear and cytoplasmic elements of neurons. Western blot revealed IgG binding to the 34- and 29-kd bands and IgM binding to the 44-, 37-, and 29-kd bands. The IgM reactivity gradually reduced. There was no identifiable neoplasm and the ataxia gradually improved. These findings suggest a role for autoimmune mechanisms in the pathogenesis of acute cerebellar ataxia.