COMMENT Myoclonus and its relation to monoamine, GABA and other receptors is reviewed from the Departments of Neurology and Pediatrics, University of Southern California School of Medicine, Los Angeles, CA [2]. The term myoclonus was first used in 1881 by Freidreich with reference to a progressive movement disorder of a gradual onset in a middle-aged man. By 1891 Unverricht had written a book on myoclonus, describing a family with myoclonus and progressive deterioration. Snodgrass, in the present article, classifies myoclonus in four categories: a) stimulus-sensitive myoclonus, b) stimulus-insensitive myoclonus, c) sleep myoclonus, and d) asterexis and negative myoclonus. Distinction between epileptic and nonepileptic myoclonus is often difficult. Posthypoxic action myoclonus (Lance-Adams syndrome) is associated with reduced CSF levels of 5-HIAA, the serotonin metabolite, and 50% respond to treatment with 5-HTP. Benzodiazepines and valproic acid are the most useful drugs for patients unresponsive to HIP. Various animal models of myoclonus are described. [3]

“Severe myoclonic epilepsy of infancy” is discussed by Hurst DL [4] from the Department of Medical and Surgical Neurology, Texas Tech University, Lubbock, Texas. The central features of this syndrome include: 1) normal development before the onset of seizure activity, 2) repeated prolonged febrile seizures, 3) later onset of mixed/myoclonus epilepsy, 4) developmental slowing with onset of seizure activity, and 5) evolving EEG abnormalities. The incidence of the syndrome is estimated at one in 40,000 children. Dravet, who first described the syndrome in 1978, found a 30% prevalence in a group of 142 children with myoclonic epilepsy. A more vigorous, rather than conservative, approach to the management of complex febrile seizures might be suggested by this report.