Ephedrine therapy in eight patients with congenital myasthenic syndrome due to DOK7 mutations

Dept. of Pediatric Neurology, University of Essen, Germany.
Neuromuscular Disorders (Impact Factor: 2.64). 10/2009; 19(12):828-32. DOI: 10.1016/j.nmd.2009.09.008
Source: PubMed


In congenital myasthenic syndrome with DOK7 mutations ephedrine was reported to be beneficial in single patients. We carried out a small, open and prospective cohort study in eight European patients manifesting from birth to 12 years. Five patients showed limb-girdle and facial weakness, three a floppy infant syndrome with bulbar symptoms and/or respiratory distress. Ephedrine was started with 25 mg/day and slowly increased to 75-100 mg/day. Within weeks after starting therapy an improvement was observed in all patients and clinical follow-up disclosed positive effects more pronounced on proximal muscle weakness and strength using MRC scale. Effects on facial weakness were less pronounced. Vital capacity measurements and repetitive stimulation tests did not improve in the same way as clinical symptoms did. These investigations are appropriate to confirm the diagnosis in case of pathological results, but they might not be appropriate means to monitor patients under ephedrine therapy.

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Available from: Hanns Lochmuller, Jan 22, 2016
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    • "Many forms of CMS also present low levels of AChR at the NMJ. Although the underlying mechanisms for that might differ between distinct mutations, the finding that sympathomimetic substances, such as ephedrine and salbutamol, can significantly improve these patients' symptoms (Edgeworth, 1930; Schara et al., 2009; Lashley et al., 2010; Liewluck et al., 2011; Finlayson et al., 2013), suggests an involvement of catecholamines in AChR turnover. Since ephedrine and salbutamol both can activate β2-ARs and thus affect cAMP production, this could point to a possible role of cAMP in stabilizing AChR and/or leading to higher AChR expression. "
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    • "Ephedrine has been shown to be helpful, with patients reporting an improvement over a 1–24 month period [5] [6]. However, ephedrine has both a and b-adrenergic effects and concern remains regarding central and cardiac adverse effects, particularly with long term use in children. "
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