[Rapid progressive HTLV-1-associated myelopathy with bronchoalveolar lesions and a long spinal cord lesion extending to almost the entire spinal cord].

We report the case of a 73-year-old woman with progressive gait disturbance for several months and an impaired standing ability. Her symptoms were lower-limb-dominant spastic tetraplegia with normal muscle tonus, hyperreflexia with positive Babinski sign, hypothermesthesia and hypalgesia in bilateral lower limbs, and dysesthesia in the fingers of both hands. Magnetic resonance (MR) images revealed a long lesion extending to nearly the entire spinal cord, and chest computed tomography (CT) revealed diffuse multiple small nodular lesions in the lower parts of the right and left lungs. High titers of human T-cell lymphotropic virus (HTLV)-1 antibodies in the serum and CSF, large amount of HTLV-1 provirus and neopterin in the CSF, and lymphocytic infiltration around bronchioles in pulmonary biopsy specimens indicated the presence of HTLV-1-associated myelopathy (HAM) with HTLV-1-associated bronchiolo-alveolar disorder (HABA). Her neurologic symptoms and the lesions in the spinal cord and lungs rapidly improved after corticosteroid pulse therapy. Rapid progressive HAM should be considered as a differential diagnosis of subacute spastic paraparesis with long spinal cord lesions. Further, careful investigation to detect pulmonary lesions, which are reported to be asymptomatic in most cases, is useful to confirm a diagnosis of HAM.