[HTLV-I associated myelopathy with bilateral abductor vocal cord paralysis--case report]

We have reported a 50-year-old woman with HTLV-I associated myelopathy (HAM) who had bilateral abductor vocal cord paralysis. The symptoms and signs were slowly progressive spastic paraplegia, dysuria, inspiratory stridor, and snoring during sleep. She had no hoarseness. Titers of anti-HTLV-I antibody were elevated in both the serum and cerebrospinal fluid. FEV1.0% on the spirogram was reduced to 66%. The fiberscopic examination demonstrated the abductor limitation of the vocal cords during the inspiratory phase. During induced sleep after the intravenous administration of thiopental sodium, this abductor paralysis was worsened, producing a high pitched inspiratory stridor. The adduction was not disturbed at all. Needle electromyogram of the posterior crico-arytenoid muscle which is a sole abductor muscle revealed the high amplitude up to approximately 1.0 mV (normal less than 0.8 mV) with poor interference pattern, indicating neurogenic changes. After 2 months course of prednisolone (60 mg/alternative day), FEV1.0% was recovered to be 92% with the improvement of the gait disturbance, which suggests the abductor vocal cord paralysis is related to HAM. The abductor vocal cord paralysis in HAM would require a careful follow-up observation to protect the respiratory failure in the advanced stage.