Utility of Rapid Exome Sequencing in the Diagnosis of a Rare Congenital Myasthenic Syndromes in a Preterm InfantFunding None.
24 February 2020
19 April 2020
26 May 2020 (online)
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.
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.
All authors approved the final manuscript as submitted and agree to be accountable for all aspects of this work.
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