Electrophysiological studies of myoclonus in sialidosis type 2.
Electrophysiological investigation was performed in 3 patients with beta-galactosidase and sialidase deficiencies (sialidosis type 2) in order to elucidate the underlying mechanism of intention myoclonus. It is a rare neuronal storage disease that begins in childhood with mental retardation, skeletal abnormalities, progressive myoclonus and cherry-red spots in the macula. Electrophysiological studies showed paroxysmal activities in the EEG, consistent temporal relationship between the EEG spikes and myoclonic jerks demonstrated by jerk-locked averaging, high amplitude somatosensory evoked potentials with altered wave form, and enhanced long-loop reflexes. These results suggest that there is a hyperexcitability of the cerebral cortex, which results in induction of intention myoclonus. The intention myoclonus in sialidosis type 2 is consistent with 'cortical reflex' myoclonus described in progressive myoclonic epilepsy due to various etiologies.
Tobimatsu
S
S
Fukui
R
R
Shibasaki
H
H
Kato
M
M
Kuroiwa
Y
Y
D000328:Adult; D002540:Cerebral Cortex / Q000503:physiopathology; D003677:Deficiency Diseases / Q000150:complications / Q000503:physiopathology*; D004569:Electroencephalography; D004576:Electromyography; D004594:Electrophysiology; D005073:Evoked Potentials, Somatosensory; D005260:Female; D006801:Humans; D008297:Male; D009207:Myoclonus / Q000209:etiology / Q000503:physiopathology*; D009439:Neuraminidase / Q000172:deficiency*; D001616:beta-Galactosidase / Q000172:deficiency
D009439:Neuraminidase; D001616:beta-Galactosidase