[Tropical spastic paraparesis due to HTLV-I. 4 case reports and literature review]

We describe the clinical, radiological, neurophysiological and biological characteristics of 4 patients suffering from tropical spastic paraparesis due to a HTLV-I infection. Patient 1 immigrated in Europe at the age of 16 from Caribbean islands. Patient 2 was a White male Caucasian who lived during several years with a prostitute also native of Caribbean islands. Patient 3 was a Black male Zaïrian and Patient 4 was a female of mixed race who lived many years in Zaäire and in Senegal. All the 4 patients presented with walking difficulties, a spastic paraparesis, urinary disturbances and often, severe constipation. The diagnosis was based on a positive ELISA test for HTLV-I antibodies, confirmed in 2 cases each by Western blots and detection of the viral genome by the Polymerase Chain Reaction. In all cases, CSF pleocytosis and CSF-restricted oligoclonal IgG bands were observed. MRI of the spinal cord showed a global atrophy in 3 cases. Cerebral MRI revealed unusual extensive, progressive and symmetric lesions of the white matter in Patient 1, and some patchy periventricular lesions in Patient 4; this examination was normal in the two other cases. Sensory evoked potentials indicated abnormalities of central conduction velocities at the level of the posterior columns. The pathogenesis of tropical spastic paraparesis is briefly discussed.