OBJECTIVES: To define the neuromuscular involvement in 'mitochondrial' patients with clinical evidence of a neuromuscular disorder, and to evaluate if the proposed electrophysiological protocol was suitable to reveal a subclinical neuropathy or myopathy in 'mitochondrial' patients with no clinical sign of a neuromuscular disturbance. METHODS: Quantitative concentric needle electromyography (CNEMG), single fiber electromyography (SFEMG) and nerve conduction studies (NCS) were performed in 33 patients with mitochondrial cytopathies. Lastly, we studied 9 clinically unaffected relatives. RESULTS: NCS were abnormal in 18% of patients, with CNEMG and SFEMG in 58% of cases, but there was not a complete overlapping of the positivity of the different techniques. No asymptomatic relatives showed abnormalities of the electrophysiological studies. CONCLUSIONS: Electrophysiological findings did not correlate with any specific biochemical or genetic defect, but were consistent with clinical diagnosis in almost all of the patients with clinical signs of myopathy and/or neuropathy. Increase of both SFEMG jitter and fiber density was significantly tied to a neuropathic process. CNEMG and SFEMG were altered in about 30% of subjects without clinical signs of myopathy or neuropathy and were therefore able to reveal a subclinical involvement of neuromuscular system in some patients who had external ophthalmoplegia or retinitis only.
OBJECTIVES: To define the neuromuscular involvement in 'mitochondrial' patients with clinical evidence of a neuromuscular disorder, and to evaluate if the proposed electrophysiological protocol was suitable to reveal a subclinical neuropathy or myopathy in 'mitochondrial' patients with no clinical sign of a neuromuscular disturbance. METHODS: Quantitative concentric needle electromyography (CNEMG), single fiber electromyography (SFEMG) and nerve conduction studies (NCS) were performed in 33 patients with mitochondrial cytopathies. Lastly, we studied 9 clinically unaffected relatives. RESULTS: NCS were abnormal in 18% of patients, with CNEMG and SFEMG in 58% of cases, but there was not a complete overlapping of the positivity of the different techniques. No asymptomatic relatives showed abnormalities of the electrophysiological studies. CONCLUSIONS: Electrophysiological findings did not correlate with any specific biochemical or genetic defect, but were consistent with clinical diagnosis in almost all of the patients with clinical signs of myopathy and/or neuropathy. Increase of both SFEMG jitter and fiber density was significantly tied to a neuropathic process. CNEMG and SFEMG were altered in about 30% of subjects without clinical signs of myopathy or neuropathy and were therefore able to reveal a subclinical involvement of neuromuscular system in some patients who had external ophthalmoplegia or retinitis only.
Authors: Vasilios C Constantinides; Maria Martha Papahatzaki; Georgios K Papadimas; Nikos Karandreas; Thomas Zambelis; Panagiotis Kokotis; Panagiota Manda Journal: In Vivo Date: 2018 Nov-Dec Impact factor: 2.155
Authors: Sumit Parikh; Amy Goldstein; Amel Karaa; Mary Kay Koenig; Irina Anselm; Catherine Brunel-Guitton; John Christodoulou; Bruce H Cohen; David Dimmock; Gregory M Enns; Marni J Falk; Annette Feigenbaum; Richard E Frye; Jaya Ganesh; David Griesemer; Richard Haas; Rita Horvath; Mark Korson; Michael C Kruer; Michelangelo Mancuso; Shana McCormack; Marie Josee Raboisson; Tyler Reimschisel; Ramona Salvarinova; Russell P Saneto; Fernando Scaglia; John Shoffner; Peter W Stacpoole; Carolyn M Sue; Mark Tarnopolsky; Clara Van Karnebeek; Lynne A Wolfe; Zarazuela Zolkipli Cunningham; Shamima Rahman; Patrick F Chinnery Journal: Genet Med Date: 2017-07-27 Impact factor: 8.822
Authors: Luis P Braz; Yi Shiau Ng; Gráinne S Gorman; Andrew M Schaefer; Robert McFarland; Robert W Taylor; Doug M Turnbull; Roger G Whittaker Journal: Neurol Clin Pract Date: 2021-04
Authors: Diana Lehmann; Malte E Kornhuber; Carolina Clajus; Charlotte L Alston; Andreas Wienke; Marcus Deschauer; Robert W Taylor; Stephan Zierz Journal: Neurol Genet Date: 2016-10-19