Long-term evolution of EEG in Unverricht-Lundborg disease

Abstract

To describe the EEG characteristics of patients with Unverricht-Lundborg disease (ULD) and their changes during the long-term evolution of the disease. A retrospective study including all patients with ULD confirmed by molecular biology and more than 15years' duration of disease progression at the time of inclusion. EEGs were recorded at inclusion, 2years and 5years of follow-up. Patients who discontinued treatment during follow-up had an EEG monitoring 1year after reintroduction of therapy. Forty-seven EEGs were performed in 17patients. The mean age at onset was 12.0±5.5years. The mean duration of follow-up was 26.5±6.9years. The average background rhythm was 8.2 c/s, and was normal in 30EEGs (64%), slow in 17 (36%) and disorganized in 11 (23%). Epileptic abnormalities were found in 22EEGs (47%). Myoclonic jerks were found in 13EEGs (28%). After re-adaptation of antiepileptic medication in patients who had previously stopped treatment, control EEG showed a normal background rhythm with no epileptic abnormalities throughout the monitoring period. This study shows that the progressive disappearance of EEG abnormalities is rather due to antiepileptic treatment than a gradual spontaneous tendency to decrease over time.