TROPICAL SPASTIC PARAPARESIS AND HUMAN T CELL LYMPHOTROPIC VIRUS TYPE 1 IN THE UNITED KINGDOM

Twenty-one patients with tropical spastic paraparesis (TSP), all of whom were born in the Caribbean and who had migrated to the United Kingdom, are described. All had a progressive spastic paraparesis developing many years after immigration and all 19 tested had antibodies to the human T cell lymphotropic retrovirus type 1 (HTLV1). The clinical and laboratory features and visual, auditory and somatosensory evoked potentials are described Details of magnetic resonance scanning of the brain and, in a few cases, the spinal cord are compared with those found in multiple sclerosis. The antibody titres to HTLVI assessed by particle agglutination, Western blot, antibody-directed cell mediated cytotoxicity and pseudotype neutralization were higher than in asymptomatic infected relatives and in patients with adult T cell leukaemia. Some, but not all, of the IgG oligoclonal bands in the CSF were directed against HTLVI IgM oligoclonal bands directed against HTLVI were found in 2 patients Sixty of the 64 first degree relatives of 11 Jamaican patients with TSP were traced in the UK and the Caribbean; 20–30% of those born in the Caribbean had antibodies to HTLVI, irrespective of their present place of residence, whilst none of those born in the UK, who were the children of the patients, had antibodies The original pathological material obtained from the Caribbean by Montgomery et al. (1964) is reviewed These results are discussed in relation to animal retroviral neurological diseases, particularly visna in sheep which has clinical and pathological features closely similar to TSP. It is proposed that TSP is due to a HTLVI infected lymphocyte/macrophage immune-mediated inflammatory response in the spinal cord.