The correspondents comment on the reports of Gessain et al. (above). They also report 6 patients (4 women, 2 men) aged 25-58 years, with slowly progressive spastic paraparesis. These cases were seen in the Kagoshima prefecture of Japan, where the prevalence of anti-HTLV-I is about 16%. The 6 had very high anti-HTLV-I titres by latex agglutination in serum (512-8192) and in CSF (64-512). Out of 78 neurological control patients 12 were seropositive (serum titre 16-2048). Only one control had anti-HTLV-I in CSF. In the paraparetic patients Western blot of CSF showed 2 clear bands (p24 and p32). Their white blood cell counts were normal though ATLL-associated lymphocyte appearances were seen in some. Four of 6 were treated with prednisolone in a tapering dose with improvement in gait, sensation and sphincter control. Subsequently Western blot anti-HTLV-I testing of the CSF of previously undiagnosed patients has revealed 7 more cases. The authors suggest that this spastic paraparesis be called HTLV-I-associated myelopathy (HAM).

In a subsequent letter (ibid., ii, 104-105) they report a further 17 cases, who also lived in Kagoshima prefecture. Nine (39%) of the 23 cases had had a blood transfusion before onset of symptoms, a much higher frequency than in 3 control groups; patients with adult T-cell leukaemia/lymphoma, internal medicine inpatients, and hospital staff.newline˜P. Mortimer