Late-onset myoclonic epilepsy in Down's syndrome (LOMEDS).
The aim of this paper is to report a patient with late-onset myoclonic epilepsy in Down's syndrome (LOMEDS) as a differential diagnosis of adult-onset progressive myoclonic epilepsies. A 55-year-old male with Down's syndrome (DS) is described who developed progressively frequent myoclonus and generalized myoclonic-tonic seizures (GMTSs) at the age of 52. EEG recordings demonstrated background slowing and generalized polyspike-wave discharges occasionally associated with myoclonic jerks, leading to the classification of the primary generalized epileptic myoclonus. Descriptions of late-onset epilepsy in DS patients are rare. However, a review of the pertinent literature revealed at least two other cases of elderly DS patients developing progressive myoclonic epilepsy after the onset of dementia. We suggest that late-onset myoclonic epilepsy in Down's syndrome as characterized here should be considered in the differential diagnosis of adult-onset myoclonic epilepsies. LOMEDS apparently shares features with myoclonic epilepsy in Alzheimer's disease (AD) and Unverricht-Lundborg disease (ULD) caused by a mutation on chromosome 21. Since life expectation of DS patients has markedly increased, LOMEDS may be more frequent than currently acknowledged.
Klinik für Neurologie, Philipps-University Marburg, Germany.
J C
JC
Möller
H M
HM
Hamer
W H
WH
Oertel
F
F
Rosenow
D000544:Alzheimer Disease / Q000150:complications / Q000175:diagnosis; D001921:Brain / Q000503:physiopathology; D003937:Diagnosis, Differential; D004314:Down Syndrome / Q000150:complications*; D004569:Electroencephalography; D004831:Epilepsies, Myoclonic / Q000150:complications* / Q000503:physiopathology; D006801:Humans; D008875:Middle Aged; D020194:Unverricht-Lundborg Syndrome / Q000175:diagnosis