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Case Reports
. 2017 Sep 29:8:520.
doi: 10.3389/fneur.2017.00520. eCollection 2017.

Molecular Diagnosis of Myoclonus Epilepsy Associated with Ragged-Red Fibers Syndrome in the Absence of Ragged Red Fibers

Sun Yeong Park  1 , Se Hoon Kim  2 , Young-Mock Lee  1
Affiliations
Case Reports

Molecular Diagnosis of Myoclonus Epilepsy Associated with Ragged-Red Fibers Syndrome in the Absence of Ragged Red Fibers

Sun Yeong Park et al. Front Neurol. .

Abstract

Myoclonus epilepsy with ragged-red fibers (MERRFs), an inherited mitochondrial disorder, has characteristic morphological changes of ragged-red fibers (RRFs) in muscle biopsy, in the absence of which mitochondrial etiology is usually not considered in patients with phenotypes suggestive of MERRF. In these circumstances, MERRF can only be diagnosed using genetic analyses. The symptoms, pathological findings, and imaging results being age dependent, we can construct a protocol based on these characteristics to understand the disease's natural course and to manage patients more effectively. The absence of RRFs should not preclude a MERRF diagnosis.

Keywords: mitochondria; molecular diagnosis; muscle; myoclonus epilepsy with ragged-red fibers; pathology; ragged-red fibers.

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Figures

Figure 1
Figure 1
(A,B) Axial and coronal FLAIR MRI at 4 years of age showed normal findings. (C,D) Axial T2-weighted MRI and coronal FLAIR MRI at 6 years of age showed no significant interval change. FLAIR, fluid attenuated inversion recovery; MRI, magnetic resonance imaging.
Figure 2
Figure 2
H&E (A) and Gomori-modified TRC (B) showed no ragged-red fiber (RRF). Ultrastructural study showed increased large mitochondria (megaconia) in the intermyofibrillar and subsarcolemmal area [(C) 10,000× and (D) 15,000×].
See this image and copyright information in PMC

References

    1. Chou SJ, Tseng WL, Chen CT, Lai YF, Chien CS, Chang YL, et al. Impaired ROS scavenging system in human induced pluripotent stem cells generated from patients with MERRF syndrome. Sci Rep (2016) 6:23661.10.1038/srep23661 - DOI - PMC - PubMed
    1. DiMauro S, Hirano M. MERRF. In: Pagon RA, Adam MP, Ardinger HH, Wallace SE, Amemiya A, Bean LJH, et al., editors. GeneReviews(R). Seattle, WA: University of Washington; (1993).
    1. Wiedemann FR, Bartels C, Kirches E, Mawrin C, Wallesch CW. Unusual presentations of patients with the mitochondrial MERRF mutation A8344G. Clin Neurol Neurosurg (2008) 110:859–63.10.1016/j.clineuro.2008.06.010 - DOI - PubMed
    1. DiMauro S, Hirano M, Kaufmann P, Tanji K, Sano M, Shungu DC, et al. Clinical features and genetics of myoclonic epilepsy with ragged red fibers. Adv Neurol (2002) 89:217–29. - PubMed
    1. Mancuso M, Petrozzi L, Filosto M, Nesti C, Rocchi A, Choub A, et al. MERRF syndrome without ragged-red fibers: the need for molecular diagnosis. Biochem Biophys Res Commun (2007) 354:1058–60.10.1016/j.bbrc.2007.01.099 - DOI - PubMed

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