Tropical spastic paraparesis and cerebelar atrophy

Abstract

Background: Lymphotropic Virus Type I (HTLV-I) causes Tropical Spastic Paraparesis (PET) in 3% of infected patients; in whom have been described exceptionally associated a central vestibular syndrome and cerebellar atrophy. Those alterations of CNS are predominating in women. Purpose: To present a new case of the exceptional form of spastic paraparesis and cerebellar atrophy. To suggest a pathogenic interpretation of female predominance in this pathology Patient: A 20-year-old woman of small size, infected with HTLV-I during lactation. Approximately at 15 years of age he started a progressive ataxo-spastic syndrome, later cognitive damage and cerebellar atrophy were added. Upon admission, high viral load and high levels of Tax protein, leukemoid lymphocytes and Sicca syndrome were observed. Conclusion: PET is an axonopathy of the central motor pathway, originated by a chronic disturbance of axoplasmic transport, attributable to the action of elevated levels of Tax protein in the CNS. In addition axons of the oval center (cognitive impairment) or the cerebellar vermis (central vestibular syndrome) are occasionally damaged. Although PET mainly affects 3: 1 women, this prevalence increases in accordance with the increase of neurological damage. The apparent greater vulnerability of the CNS in women would be due to the higher concentration of Tax in the CNS of them, originated in the adverse relationship between body weight and absolute amount of Tax, which was evident in our patient, who gave the key to this hypothesis.