Abstract
Unverricht-Lundborg disease (ULD), a type of progressive myoclonus epilepsy, is an autosomal recessive disorder with point mutation in gene encoding Cystatine B. It is well known that ULD is so similar to focal epilepsy or other epilepsy syndromes because of its slow progression that it leads to a misdiagnosis, and also known that ULD is worsened by phenytoin (PHT) treatment. The gene encoding Cystatine B is the only gene known to be associated with ULD.
We found a patient who had characteristic symptoms as high amplitude evoked potentials, hyper photosensitivity and frequent myoclonus at morning. We diagnosed her as ULD by clinical features, although she didn't have genetic abnormality, like an expansion of a 12-nucleotide repeats often expressed in ULD patients. She had been misdiagnosed as focal epilepsy and received PHT treatment for more than 10 years until we diagnosed her as ULD. Changing PHT to clonazepam and piracetam, betterment of her living conditions was observed. It is suggested that we should be careful in ULD diagnosis as well as initial choice of anti epileptic drug. And we should know the features of ULD enough.
