Clinical and Genetic Features of Congenital Myasthenic Syndromes due to CHAT Mutations: Case Report and Literature Review

Abstract

Congenital myasthenic syndromes (CMS) are neuromuscular transmission disorders caused by mutations in genes encoding neuromuscular junction proteins. CMS due to choline acetyltransferase (CHAT) gene is characterized by episodic apnea. We report a case of a 12-month-old female patient presented with recurrent episodic apnea carrying a mutation in CHAT gene, p.I336T. Furthermore, we describe the genetic and clinical findings in 44 CMS patients due to CHAT mutations in the literature up to date. Episodes of apnea and respiratory insufficiency are the hallmarks of CHAT mutations. Clinical manifestations usually provoked by infections and fever. CMS due to CHAT mutations are rare, but it is important to diagnosis. Early diagnosis and appropriate treatment can improve morbidity and mortality.

Keywords

congenital myasthenic syndrome - choline acetyltransferase - episodic apnea

Author Contributions

PA prepared the original manuscript. NOD and PG contributed to the revision of the final manuscript. DC assisted in the preparation of the manuscript.

Declaration of Conflicting Interest

The authors declare no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

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