Pharmacological Strategy for Congenital Myasthenic Syndrome with CHRNE Mutations: A Meta-Analysis of Case Reports

Background: Congenital myasthenic syndromes (CMSs) are a heterogeneous group of neuromuscular disorders. Mutations of the nicotinic acetylcholine receptor epsilon subunit gene (CHRNE) are the most common causes of these disorders. CMSs are gaining increasing recognition by clinicians. However, pharmacological treatment of CMS with CHRNE mutations has only been discussed in a small number of case reports. Objective: This study aims to determine how to choose an appropriate pharmacological strategy for CMS with CHRNE mutations. Methods: A meta-analysis was performed. PubMed, MEDLINE, Web of Science, and Cochrane Library databases were searched for studies published in English prior to June 1, 2020. The extracted data included clinical information, gene mutations, pharmacological treatment, and treatment effects. Results: A total of 48 studies and 208 CMS patients with CHRNE mutations were included in our meta-analysis. Ten different pharmacological strategies were used in these patients. Our research found that β2-adrenergic receptor agonists had the best treatment effect for CMS patients with CHRNE mutations, especially in patients with primary AChR deficiency. In addition, our analysis found no evidence that age at disease onset influences the treatment results. Conclusion: This meta-analysis provides evidence that (1) β2-adrenergic receptor agonist therapy could be the first choice of pharmacological strategy for treating CMS with CHRNE mutations; (2) a single-drug-regime, rather than a combination therapy, should be the first choice of treatment; and (3) it is never too late to initiate pharmacological treatment.