COVID-19 in Patients with Myasthenia Gravis: Mechanisms of Respiratory Failure

This report describes a patient with thymomatous myasthenia gravis (MG) with aplastic anemia in pharmacological remission and COVID-19 who developed respiratory failure in the course of the disease and reviews the published literature on this topic. Analysis of the clinical characteristics of the eight patients with MG including our patient suggests two possible mechanisms for respiratory failure: myasthenic crisis (MC) or pulmonary complications of COVID-19. Patients with MC were young women in high-grade MGFA Class whereas patients with respiratory failure due to pulmonary complications of COVID-19 were elderly men in pharmacological remission or MGFA Class I. These observations suggest that COVID-19, like other infections, may precipitate MC in patients with severe grade MG before COVID-19. The only differentiating feature between the two types of failure was severity myasthenic weakness. This clinical distinction has management implications. These observations need to be validated in a larger sample.