[A case of HTLV-I associated myelopathy presenting with cerebellar signs as initial and principal manifestations]

We reported a 75-year-old woman with HTLV-I associated myelopathy (HAM) presenting with cerebellar signs. She was admitted to our hospital because of walking unsteadiness, which initially appeared 3 years previously with gradual worsening. Neurological examination revealed limb and truncal ataxia, cerebellar type dysfunction of eye movement, pyramidal sign, diminished vibration sense and neurogenic bladder. Anti HTLV-I antibody titers in serum and CSF were markedly elevated. MRI revealed abnormal signals in cerebral white matter, mild cerebellar atrophy and thoracic cord atrophy. Cerebellar signs and symptoms were initial and main neurological manifestations in this patient, which were improved by steroid therapy. We considered this case was unique among HAM, because cerebellum was considered her main lesions.