Myasthenia gravis, acute transverse myelitis, and HTLV-I.

We present the unusual case of a 49-year-old female carrier of HTLV-I with myasthenia gravis who presented with acute transverse myelitis. Laboratory data suggested a recent infection with varicella zoster virus and demyelination by an autoimmune process in the central nervous system. Adult T-cell leukemia-like cells were observed in the cerebrospinal fluid. T-cell-mediated immune responses modulated by HTLV-I infection may be involved in the pathogenesis of myasthenia gravis and acute transverse myelitis in this case.