title: Overlapping syndrome of MERRF and MELAS: molecular and neuroradiological studies.
abstract: We describe a 42-year-old woman with overlapping syndrome of MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes) and MERRF (myoclonus epilepsy and ragged-red fibers). Clinically, she had episodic headache, stroke-like episode with left hemiparesis and lactic acidosis commonly found in MELAS syndrome. However, myoclonus seizure, and ataxia with dyssynergic gait characteristic of MERRF were also noted. Computed tomographic scans showed a right temporo-parietal hypodense lesion. The lesion disappeared 20 months later, even magnetic resonance images also failed to reveal this abnormality. A molecular analysis of mitochondrial DNA was conducted by using restriction endonucleases ApaI and NaeI. A transition from A to G was found at the nucleotide position 3243, but not found at the 8344th nucleotide pair. In this report, we document the fluctuating CT changes and emphasize the importance of molecular analysis in patients with overlapping syndrome of mitochondrial encephalomyopathies.
authors.affiliation: Department of Neurology, Chang Gung Memorial Hospital, Taipei, Taiwan, R.O.C.
authors.forename: R S
authors.initials: RS
authors.lastname: Chen
authors.forename: C C
authors.initials: CC
authors.lastname: Huang
authors.forename: C C
authors.initials: CC
authors.lastname: Lee
authors.forename: Y Y
authors.initials: YY
authors.lastname: Wai
authors.forename: M S
authors.initials: MS
authors.lastname: Hsi
authors.forename: C Y
authors.initials: CY
authors.lastname: Pang
authors.forename: Y H
authors.initials: YH
authors.lastname: Wei
mesh_terms: D000328:Adult; D001482:Base Composition / Q000235:genetics; D001706:Biopsy; D001921:Brain / Q000473:pathology; D004272:DNA, Mitochondrial / Q000235:genetics*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D017243:MERRF Syndrome / Q000175:diagnosis / Q000235:genetics* / Q000473:pathology; D008279:Magnetic Resonance Imaging; D009132:Muscles / Q000473:pathology; D009460:Neurologic Examination; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D014057:Tomography, X-Ray Computed
chemical_list: D004272:DNA, Mitochondrial