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

Indrani Bhattacharjee; Neil Friedman; Ricardio J. Rodriguez

doi:10.1055/s-0040-1712177

Journal of Pediatric Neurology, Table of Contents

Journal of Pediatric Neurology 2021; 19(01): 059-061
DOI: 10.1055/s-0040-1712177

Case Report

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

Indrani Bhattacharjee

¹Department of Neonatology, Cleveland Clinic Children's Hospital, Cleveland, Ohio, United States

,

Neil Friedman

²Department of Neurology, Phoenix Children's Hospital, Phoenix, Arizona, United States

,

Ricardio J. Rodriguez

¹Department of Neonatology, Cleveland Clinic Children's Hospital, Cleveland, Ohio, United States

› Author Affiliations

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

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References

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