Leucodystrophy of late onset in two members of a family

We report 2 cases of demyelinating disease of unusually late onset in a mother and her son. The late onset of symptoms, at the age of 63 years in the mother's case, is rare. The onset in the son was at the age of 35 years. The relatively few adult cases previously reported range in age from 25 to 65 years, but only 2 cases in persons over the age of 60 could be found in the literature. The clinical and neuropathological findings are described.