Amelioration of disabling myoclonus in a case of DRPLA by levetiracetam.

We report on an 18-year-old male patient with dentatorubral-pallidoluysian atrophy (DRPLA) (number of CAG repeats: 68) with progressive myoclonus epilepsy (PME), who showed a dramatic response to levetiracetam in terms of the intensity of myoclonus. He began to have convulsive seizures and myoclonus at 7 and 10 years of age, respectively, and his intelligence deteriorated from 12 years of age. EEG showed multifocal and diffuse spike-and-wave complexes. His convulsive seizures were suppressed from 13 years of age. At 17 years of age, the patient showed gradual intensification of erratic segmental positive myoclonus as well as frequent atonic falls that were probably attributable to negative myoclonus. Back averaging of EEG data revealed cortical discharges associated with positive myoclonus. Photosensitive myoclonic seizures were also observed. The administration of levetiracetam alleviated positive myoclonus and suppressed atonic falls, resulting in a remarkable improvement in the patient's quality of daily life. Reports on the efficacy of levetiracetam for myoclonus in DRPLA are still rare, though its effect on PME is known in the context of other neurological disorders. Thus levetiracetam should be subjected to clinical trials as a means of disabling myoclonus in DRPLA.