Herpes zoster motor neuropathy in a patient with previous motor paresis secondary to Vogt-Koyanagi-Harada disease.

Motor involvement in herpes zoster is very infrequent, occurring in 3%-5% of cases, and it is caused by extension of the inflammatory process to the anterior horn motor neurons, with the subsequent development of segmental motor paralysis. The authors report a 37-yr-old woman with history of paresis in both lower limbs secondary to spinal cord atrophy associated with Vogt-Koyanagi-Harada disease and immunosuppression caused by chronic corticosteroid and azathioprine treatment of ulcerative colitis, who developed worsening of her baseline residual muscle strength in the right lower limb shortly after herpes zoster eruption. Electromyography revealed acute denervation in territories corresponding to L3-L4 and moderate widespread axonal polyneuropathy affecting both lower limbs. The patient recovered her baseline muscle strength after this event. To the best of the authors' knowledge, this is the first reported case of herpes zoster motor neuropathy in a patient with a previous motor sequel.