Spectrum of epilepsy in Wilson's disease with electroencephalographic, MR imaging and pathological correlates.

BACKGROUND: Seizures are uncommon in Wilson's disease.

OBJECTIVE: To analyze profile of seizures in WD and to correlate with EEG and MR imaging observations.

SUBJECTS AND METHODS: 41/490 patients (8.3%) of WD were documented to have seizures. Autopsy observations were available in 3 cases.

RESULTS: The age at onset of seizures was 12.8+/-5.7years. Seizure - preceded the onset of characteristic features of WD (19.5%); occurred concurrently (46.3%); or, followed de-coppering therapy (29.2%) and occurred as terminal event (4.8%). The types of seizures were: generalized tonic-clonic - 29, simple partial - 8, complex partial - 6, partial seizures with secondary generalization - 2 and periodic myoclonus - 1. Six patients had multiple seizure types and 4 had status epilepticus. EEG abnormalities were frequent (19/24) consisting of background slowing and epileptiform discharges. MRI (n=20) revealed varying degree of atrophy and signal changes involving basal ganglia, brainstem and white matter. The duration of follow-up was 8.1+/-9.2years. The outcome of seizure was: no recurrence - 68.3%, breakthrough seizures - 17.1%, poor control - 9.7% and no follow-up - 4.9%. Two of them succumbed following cluster attacks. Autopsy revealed cavitatory lesions in white matter in frontal, temporal and parietal areas with varying involvement of cortical ribbon. Patients with seizures had more often white matter changes than those without. It was also noted that patients whose seizures were not controlled had MRI suggestive of cavitation of white matter, though the reverse was not true.

CONCLUSIONS: This is the largest series regarding epilepsy in WD. Seizures are not uncommon and could occur at any stage. Deafferentation of white matter tracts from cortex may contribute for seizure in WD.