First Molecular Diagnosis of a Patient with Unverricht-Lundborg Disease in Korea

Unverricht-Lundborg disease (ULD) is a form of progressive myoclonus epilepsy characterized by stimulation-induced myoclonus and seizures. This disease is an autosomal recessive disorder, and the gene CSTB, which encodes cystatin B, a cysteine protease inhibitor, is the only gene known to be associated with ULD. Although the prevalence of ULD is higher in the Baltic region of Europe and the Mediterranean, sporadic cases have occasionally been diagnosed worldwide. The patient described in the current report showed only abnormally enlarged restriction fragments of 62 dodecamer repeats, confirming ULD, that were transmitted from both her father and mother who carried the abnormally enlarged restriction fragment as heterozygotes with normal-sized fragments. We report the first case of a genetically confirmed patient with ULD in Korea.

Two Cases of Unverricht-Lundborg Disease

Unverricht-Lundborg disease(Baltic myoclonus) is one of the major causes of progressive myoclonus epilepsy. It is characterized by stimulus sensitive myoclonic seizure, generaized tonic-clonic seizure, generally synchronous polyspike and wave discharges on EEG and absence of severe or early dementia. It has usually been described in the countries around the Baltic area. But recently, it is regarded as the most common form of progressive myoclonus epilepsy in the other countries as well. We report, with the review of the literature, two patients who showed the typical features of this disorder.