Myoclonus epilepsy

HSF heat shock factor protein MERRF myoclonus epilepsy with ragged red fibers... 

A neonatal form of hepatic failure has a rapidly fatal course and frequently includes severe hypotonia, myoclonus epilepsy, and psychomotor retardation [39]. Another type (found in children aged 2-18 months) has a milder clinical course with infrequent fatal outcome [11]. Abnormal histology (steatosis, micro and macro-nodular cirrhosis) and elevated plasma or cerebrospinal fluid (CSF) lactate are consistent features of the disease, regardless of the clinical subtype. The brain is often involved in these presentations, but other organs could also be involved. Dwarfism... 

Progressive myoclonus epilepsy (G + C)-rich oligonucleotide repeat Cystatin B... 

M8. Masucci, J. P., Davidson, M., Koga, Y., Schon, E. A., and King, M. P., In vitro analysis of mutants causing myoclonus epilepsy with ragged-red fibers in the mitochondrial tRNALys gene Two genotypes produce similar phenotypes. Mol. Cell. Biol. 15, 2872-2881 (1995). 

B12. Bespalova, I. N., Adkins, S., Pranzatelli, M., and Burmeister, M., Novel cystatin B mutation and diagnostic PCR assay in an Unverricht-Lundborg progressive myoclonus epilepsy patient. Am. 

LI. Lafreniere, R. G., Rochefort, D. L., Chretien, N., Rommens, J. M., Cochins, J. I., etal., Unstable insertion in the 5 flanking region of the cystatin B gene is the most common mutation in progressive myoclonus epilepsy type 1, EPM1. Nat. Genet. 15(3), 298—302 (1997). 

T. Saha and K. Usdin, Tetraplex formation by the progressive myoclonus epilepsy type-1 repeat implications of instability in the repeat expansion diseases, FEES Lett., 2001, 491, 184-187. 

Watson, S. W., and D. Denny-Brown Myoclonus epilepsy as a symptom of diffuse neuronal disease. Arch. Neurol. Psychiat. (Chic.) 70, 151 (1953). 

C.D, Hall, F.R, Stowe, and G.K. Summer, Familial cerebellar dyssynergia and myoclonus epilepsy associated with defect of amino acid metabolism. Neurology 2 - ... 

Minassian, BA lanzano, L Meloche, M Andermann, E Rouleau, GA Delgado-Escueta, AV et al. Mutation spectrum and predicted function of laforin in Lafora s progressive myoclonus epilepsy. Neurology, 2000, 55, 341-6. 

Myoclonic epilepsy with ragged-red fibers (MERPF) is a rare syndrome which shows clear maternal inheritance and a variable clinical pattern including progressive myoclonus, cerebellar ataxia, dementia, and muscle weakness. It is associated with an A-to-G transition at position 8344 of the tRNA Lys gene in the mtDNA. The mutation is heteroplasmic and produces similar multicomplex deficiencies as are seen in KSS. 

Lafora s disease manifest an accumulation of polyglucosan, in the CNS and PNS as well as in other tissues [1]. Lafora s disease is transmitted as an autosomal recessive trait and is characterized by epilepsy, myoclonus and dementia. Other neurological manifestations include ataxia, dysarthria, spasticity and rigidity. Onset is in adolescence, and death occurs in most patients before 25 years of age. 

Valproate is now the most commonly used antiepileptic drug worldwide. It is the drug of choice in primary generalized epilepsy, particularly in the treatment of generalized absence, myoclonus and tonic-clonic seizures. Valproate is the drug of first choice in atypical absence and atonic seizures, for Lennox-Gastaut syndrome and myoclonic epilepsy. 

It is well established that mitochondrial function defects are not severe until the proportion of mutant mtDNA reaches a high level, which forms the basis of the concept of the threshold effect. In skeletal muscle, the level of the A3243G mutation is related to the severity of strokelike episodes, epilepsy, and dementia in patients with MELAS syndrome (C6, H14, PI). Similarly, the level of the A8344G mutation is correlated with the degree of cerebellar ataxia and myoclonus in patients with MERRF syndrome (C6). Thus, molecular genetic analysis of mtDNA mutations in muscle biopsies usually provides more definitive diagnosis of... 

Therapeutic indication Epilepsy (partial possibly generalized and myoclonus) Age-related cognitive disturbances poststroke aphasia... 

Epilepsy, myoclonus, alcohol withdrawal Muscle spasticity, akathisia Premedication... 

Nervons system Two patients, one with cr)rp-togenic focal epilepsy and the other with Dra-vet sjmdrome, had negative myoclonus and increased seizure frequency associated with continuous spike waves during slow sleep associated with levetiracetam in both cases drug withdrawal led to improvement [208 ]. 

In a retrospective study in 162 patients with epilepsy taking gabapentin, pre-existing myoclonus was worsened in two cases within 2 weeks of starting gabapentin in another case it occurred de novo [116. Withdrawal of gabapentin or clonazepam add-on treatment resulted in resolution of myoclonus with no serious sequelae in aU three cases. 

It has been hypothesized that the mechanisms whereby mefloquine increases the risk of seizures in patients with a history of seizures, which may be via altered neuronal calcium homeostasis, altered gap-junction functioning, and neuronal cell death, are particularly associated with a mutation in EPMl, a gene that is associated with progressive myoclonic epilepsy type 1, and hence altered GABA activity [10 ]. The author proposed that mefloquine should be contraindicated in people with the EPMl mutation and in those with a history of myoclonus or ataxia, or a family history of degenerative neurological disorders that are consistent with the presence of the EPMl mutation. 

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