Utility of Rapid Exome Sequencing in the Diagnosis of a Rare Congenital Myasthenic Syndromes in a Preterm Infant

Abstract

Congenital myasthenic syndromes (CMS) are rare and challenging diagnoses in preterm neonates. We presented in this case report a preterm infant with recurrent extubation failures. An exhaustive workup to rule out common etiologies of chronic ventilator dependence was negative including a neostigmine trial, acetylcholine receptor antibodies, and chromosomal microarray. Electromyography (EMG) showed features of a neuromuscular junction defect. After ruling out metabolic, inflammatory, and immune mediated causes, a rapid exome sequencing demonstrated CHRNB1 gene mutation diagnostic of autosomal dominant slow channel CMS. The patient was started on fluoxetine and nebulized salbutamol with a gradual improvement in her respiratory function over time with minimal ventilator support.

Keywords

slow-channel congenital myasthenic syndromes - preterm - extubation

Authors' Contributions

I.B. drafted the initial manuscript and reviewed and revised the manuscript. N.F. critically reviewed and revised the manuscript for important intellectual content. R.J.R. critically reviewed the manuscript for important intellectual content.

Note

All authors approved the final manuscript as submitted and agree to be accountable for all aspects of this work.

Publication History

Received: 24 February 2020

Accepted: 19 April 2020

Article published online:
26 May 2020

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