P40-T EEG characteristics in Polish patients with Unverricht-Lundborg disease

Abstract

Background Unverricht-Lundborg disease (ULD) is an autosomal recessive form of progressive myoclonus epilepsy with a wide range of neurologic and psychiatric symptoms including tonic-clonic seizures, myoclonus, ataxia, tremor, dysarthria, depression, and mild intellectual decline. The aim of the study was to describe the EEG features of patients with ULD and their changes during the long-term follow-up. Material and methods We retrospectively evaluated the EEG features of 11 patients with genetically confirmed ULD. Results We included 4 females and 7 males with the mean age 38.3 ± 7.6 years and the mean age at onset 9.4 years. The average background rhythm was 8.4 Hz and was normal in 2 patients and slightly slowed in 9. Spike and wave discharges (SWD) were found in 9 patients and photosensitivity in 2 patients. In all patients myoclonic jerks were recorded in videoEEG, most of the myoclonic movements were not time-locked to epileptiform discharges. In 3 patients SWD and myoclonic jerks were aggravated by ill -advised antiepileptic drugs (phenytoin and carbamazepine) and their frequency diminished after treatment change. Despite the increased frequency and severity of myoclonic jerks the frequency of SWD decreased gradually with time. Conclusion The most common EEG abnormalities in patients with ULD include background slowing and spike and wave discharges; epileptiform discharges can be aggravated by ill-advised antiepileptic drugs.