| Case series/case reports  

Predictive factors for a severe course of COVID-19 infection in myasthenia gravis patients with an overall impact on myasthenic outcome status and survival

Myasthenia gravis (MG) patients could be a vulnerable group in the pandemic era of Coronavirus 2019 (COVID-19) mainly due to respiratory muscle weakness, older age, and long-term immunosuppressive treatment.

In this article the authors aimed to define factors predicting the severity of COVID-19 in MG patients and risk of MG exacerbation during COVID-19. They evaluated clinical features and outcomes after COVID-19 in 93 MG patients. Thirty-five patients (38%) had severe pneumonia and we recorded 10 deaths (11%) due to COVID-19. Higher forced vital capacity (FVC) values tested before COVID-19 were shown as protective against severe infection CI95% (0.934- 0.98) as well as good control of MG measured by quantified myasthenia gravis score CI95% (1.047 – 1.232). Long term chronic corticosteroid treatment worsened the course of COVID-19 in MG patients CI95% (1.784-111.43) and this impact was positively associated with dosage (p-value 0.005). Treatment using azathioprine CI95% (0.448 – 2.935), mycophenolate mofetil CI95% (0.91 – 12.515) and ciclosporin CI95% (0.029 – 2.212) did not influence the course of COVID-19. MG patients treated by rituximab had a high risk of death caused by COVID-19 CI95% (3.216 – 383.971). Exacerbation of MG during infection was relatively rare (15%) and was not caused by remdesivir, convalescent plasma or favipiravir CI95% (0.885 – 10.87). As the most important predictors of severe COVID-19 in MG patients the authors identified unsatisfied condition of MG with lower FVC, previous long-term corticosteroid treatment especially in higher doses, older age, the presence of cancer, and recent rituximab treatment.

Michala J, Michaela T, Adam T, Magda H, Daniela V, Irena R, Iveta N, Kristyna D, Pavel D, Jiri P, Stanislav V, Josef B. Predictive factors for a severe course of COVID-19 infection in myasthenia gravis patients with an overall impact on myasthenic outcome status and survival. Eur J Neurol. 2021 Jun 3. doi: 10.1111/ene.14951