Myotonic dystrophy: a cause of acute breathlessness not to be missed

Pract Neurol. 2020 Sep 24:practneurol-2020-002573. doi: 10.1136/practneurol-2020-002573. Online ahead of print.

Abstract

Myotonic dystrophy type 1 (DM1), the most common muscular dystrophy in adults, is an autosomal dominant disorder with a wide phenotypic spectrum ranging from oligosymptomatic forms to a life-threatening, multisystem disease. People with DM1 overall have a reduced life expectancy, mainly due to respiratory or cardiac causes. There is no cure but prompt, appropriate symptom management is essential to limit disease-related complications. We present a case of DM1, unrecognised when the patient presented with recurrent type 2 respiratory failure, and initially misdiagnosed as Guillain-Barré syndrome. This misdiagnosis subsequently led to unnecessary investigation and treatment before further detailed neurological examination and collateral family history gave the diagnosis. This case highlights the importance of considering a chronic neuromuscular disorder in patients presenting with acute respiratory failure and an unusual pattern of weakness.

Keywords: Myotonic dystrophy.