An EEG study of Wilson's disease. Findings in patients and heterozygous relatives

The correlation of clinical and EEG findings was studied in 40 patients with Wilson's disease and their 57 heterozygous relations (25 children, 30 parents and 2 siblings). EEG changes in Wilson's disease were found in 84% (50% mild, 34% moderate) with but a slight predominance in patients with neurological involvement. The relatively high rate of pathological EEG findings in the hepatic or asymptomatic forms suggested the presence of subclinical CNS damage even in these cases. Diffuse episodic abnormalities were a dominant feature in all the groups under observation. As for the heterozygous relatives, a significant increase in pathological EEG findings (80-28% mild, 52% moderate to severe) was found in the heterozygous children. The changes often correlated with the clinical detection of minimal brain damage. The grossest EEG changes were seen in the youngest age group (under 10 years of age) with a subsequent tendency to abatement. In 2 cases there was an extinction of specific epileptic graphoelements which may have been the result of long-term penicillamine administration. In the adult heterozygous population (parents and siblings) there was no significant increase in the rate of pathological EEG findings compared with our control group. The authors discuss the problem of control mechanisms which have a role to play in the normalization of biochemical and probably also clinical and EEG findings in the heterozygotes.