title: Late-onset Leigh syndrome with myoclonic epilepsy with ragged-red fibers.
abstract: We report the case of a boy with myoclonic epilepsy with ragged-red fibers (MERRF) who had astatic seizures since 2 years of age and later developed ataxia, absence seizures, and myoclonus. Almost homoplasmic A8344G mutation of mitochondrial DNA (m.8344A>G mutation) was detected in lymphocytes. He developed late-onset Leigh syndrome (LS) when he contracted pneumonia at 6 years. He developed bulbar palsy and deep coma. MRI demonstrated lesions in the brainstem, basal ganglia, and cerebral cortex. Three similar cases have been reported; two carried the almost-homoplasmic m.8344A>G mutation in muscle tissue. These suggested that almost homoplastic m.8344A>G mutation developed clinical phenotype of MERRF in the early stage and late-onset Leigh syndrome in the late course of the disease.
authors.affiliation: Department of Pediatrics, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke, Tochigi, Japan.
authors.forename: Yukifumi
authors.initials: Y
authors.lastname: Monden
authors.forename: Masato
authors.initials: M
authors.lastname: Mori
authors.forename: Mari
authors.initials: M
authors.lastname: Kuwajima
authors.forename: Tamako
authors.initials: T
authors.lastname: Goto
authors.forename: Takanori
authors.initials: T
authors.lastname: Yamagata
authors.forename: Mariko Y
authors.initials: MY
authors.lastname: Momoi
mesh_terms: D001921:Brain / Q000473:pathology; D002648:Child; D004272:DNA, Mitochondrial / Q000235:genetics; D004569:Electroencephalography; D006801:Humans; D007888:Leigh Disease / Q000150:complications* / Q000235:genetics / Q000473:pathology; D017243:MERRF Syndrome / Q000150:complications* / Q000235:genetics / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D009154:Mutation / Q000235:genetics; D012150:Polymorphism, Restriction Fragment Length
chemical_list: D004272:DNA, Mitochondrial