Recurrent transverse myelitis, myasthenia gravis, and autoantibodies.

A 45-year-old man with a longstanding diagnosis of myasthenia gravis presented with four episodes of transverse myelitis in 5 years. Each episode improved after treatment with steroids. Laboratory studies revealed no evidence of multiple sclerosis or a structural spinal lesion. He had antinuclear and anti-DNA antibodies and the HLA-A1, B8, DR3 haplotype known to be associated with certain autoimmune diseases. We propose an autoimmune cause for the recurrent episodes of myelitis.