Clinical Outcomes in COVID-19 patients with pre-existing myasthenia gravis:

INTRODUCTION: Myasthenia gravis (MG) presents an additional challenge in managing COVID-19 as outcomes potentially depend on prior disease control and treatment. Yet the role of pre-existing MG in COVID-19 outcomes has not been established. METHODS: We searched PubMed, Scopus, and Web of Science databases for reports of MG patients with confirmed COVID-19 until March 2022. We analyzed data on patient demographics, chronicity, and MG control at baseline pre-COVID, treatment history and outcome following COVID infection. RESULTS: Twenty-nine publications with 119 patients (females n=75, age range 20-93 years, AChR Ab positive n= 65, MuSK Ab positive n= 5, seronegative n=14, unknown n=35) were included. Eighty-three (70%) were hospitalized, more than half with MG exacerbation. There was no significant difference in disease duration or control of MG symptoms at baseline between hospitalized and non-hospitalized. Hospitalization was associated with higher dose of daily prednisone but a comparable proportion of patients were on steroid-sparing agents. Among hospitalized patients, 40% were intubated uncorrelated with MG baseline control. Unfavorable outcome was not always associated with MG exacerbation. Amongst those discharged,75% received intravenous immunoglobulin (IVIG) or Plasmapheresis (PLEX) for MG exacerbation as compared to 67% with a fatal outcome didn’t receive either. CONCLUSION: Preexisting MG does not appear to be associated with severe COVID-19 outcomes. Higher dose of prednisone prior to COVID-19 infection is associated with increased risk of hospitalization but MG control at baseline did not determine worse outcome. IVIG/PLEX appears safe and potentially can reduce fatality in patients with COVID-19 experiencing MG exacerbation.