A Familial Case of Myoclonus-Dystonia

ABSTRACT

BACKGROUND: Myoclonus-dystonia is a rare familial disease characterized by autosomal dominant inheritance, nonor slowly progressive axial myoclonus combined with dystonic posture, normal electroencephalography (EEG) finding, and dramatic response to alcohol intake. METHODS: Clinical manifestations were studied in a family with myoclonus-dystonia. Response to alcohol intake was investigated in affected adult patients. Brain magnetic resonance imaging (MRI) and other laboratory examination were performed in 3 patients. RESULTS: Eight (male 5, female 3) of the 14 biological family members through 4 generations were found to be affected by myoclonus-dystonia on neurological examinations. Another 5 members (male 3, female 2) were suspected to be affected in family history. All eight affected members showed axial myoclonus affecting the neck, trunk, and proximal muscles of the limbs. Six of them also had dystonia affecting the neck or the distal part of the arm. Myoclonus and dystonia were ameliorated dramatically after small dose of alcohol intake. Brain MRI, EEG study, and ophthalmologic examination showed no abnormalities. CONCLUSIONS: Our patients showed clinical features compatible with myoclonus-dystonia. This is the first Korean family with myoclonus-dystonia.