Human T-cell Lymphotropic Virus Type I Associated with Amyotrophic Lateral Sclerosis Syndrome: Immunopathological Aspects and Treatment Options

Human T-cell lymphotropic virus type I (HTLV-I) is a retrovirus related to infectious myelopathies, neoplasms, lymphomas, leukemias, and amyotrophic lateral sclerosis (ALS). It is acquired through sexual transmission, transfusion of blood products, and breastfeeding. The increased expression of human endogenous retrovirus K (HERV-K) in the brain tissue of patients with ALS has been demonstrated, a finding that supports the relationship between the virus and this disease. Therapeutic options include supportive measures and symptomatic treatment with anti-inflammatory medications including steroids, cyclosporines, pentoxifylline, danazol, interferons, and vitamin C. New management proposals are being implemented with valproic acid that acts to facilitate the recognition of the virus by the immune system and with zidovudine antivirals focused on reducing viral load. The purpose of this paper is to describe a clinical case that exhibits clinical signs and evidence of motor neuron compromise as described in electrophysiology studies along with positive laboratory tests for the HTLV-I virus.