[A case of acute type adult T cell leukemia and human T-lymphotropic virus type I associated myelopathy who presented meningitis and polyradiculoneuropathy and improved with steroid treatment].

We reported a 35-year-old male patient with acute type adult T cell leukemia(ATL) and human T-lymphotropic virus type I associated myelopathy. He presented meningitis and polyradiculoneuropathy and improved with steroid treatment. He presented headache and sensory ataxia and these symptoms responded to steroid treatment. The usual clinical features of ATL were absent at onset. There existed ATL-like cells in the cerebrospinal fluid and HTLV-I proviral DNA in the blood. Therefore, we surmised that there was monoclonal hyperplasia of the infected cells. He presented ATL after 2 years remission. We pointed out that there was acute type of ATL in patients with meningitis and polyradiculoneuropathy, for which steroid treatment could be effective.