Fluctuating Weakness in an 18-Month-Boy: Congenital MyastheniaFunding None.
We report a case of an 18-month-old child who presented with motor predominant delay in attaining developmental milestones and early onset fatiguable weakness with ptosis and ophthalmoparesis. This ptosis and ophthalmoparesis typically worsened with progression of the day. Examination showed proximal weakness with preserved muscle stretch reflexes. Electrophysiology showed characteristic decrement on repetitive nerve stimulation test that localized to disorders of the neuromuscular junction. Next-generation sequencing showed a pathogenic variant of CHRNE that was responsible for congenital myasthenic syndrome. Such variants show increased improvement with salbutamol in addition to anticholinesterase inhibitors. Hence, the child was started on pyridostigmine, and the plan was to add on salbutamol on follow-up if optimal improvement does not occur.
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Received: 27 June 2020
Accepted: 22 September 2020
03 November 2020 (online)
© 2020. Thieme. All rights reserved.
Georg Thieme Verlag KG
Stuttgart · New York
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