Vaccines and myasthenia gravis: a comprehensive review and retrospective study of SARS-CoV-2 vaccination in a large cohort of myasthenic patients

Abstract

Introduction Myasthenia gravis (MG) is an autoimmune disease, for which the risk of exacerbation after vaccines is debated. The aim of this study is to review the available literature concerning safety and efficacy of vaccines in MG. In addition, we also conducted a retrospective research of MG exacerbations and new onset MG after anti-SARS-CoV-2 vaccination in a large cohort of patients. Methods A study of the available literature regarding vaccines and MG was carried out through research in the online database “Pubmed”. We also retrospectively collected data from 80 MG patients, who were followed at the Treviso Hospital and completed an anti-SARS-CoV-2 vaccination cycle. For each patient, we recorded MG exacerbations between first and second doses and within a window period of 1 day – 6 weeks after the second dose. Results We found 26 relevant articles about influenza, SARS-CoV-2 and other vaccines. No clear associations between most vaccines and MG exacerbations were found. Moreover, cases of new onset post-vaccine MG are mostly anecdotal, except for Japanese encephalitis virus vaccine. Concerning our cohort, 4/80 (5%) MG patients experienced an exacerbation within the post-vaccine window period. In addition, we report a case of new onset post-vaccine MG. Discussion Inactivated and subunit vaccines are safe and effective in MG. Although some of them, such as anti-SARS-CoV-2 vaccine, might uncommonly cause MG exacerbations, data from our review suggest that benefits still outweigh by far the potential risks, thus they should be recommended to these patients. Nevertheless, large prospective studies are needed for further investigations.

New-Onset Ocular Myasthenia Gravis After Booster Dose of COVID-19 Vaccine

“…Studies of SARS-CoV-2 vaccination in patients with established diagnosis of MG suggest that it might rarely lead to disease worsening [11,12]. In a retrospective study on an Italian cohort of 80 patients, transient worsening after vaccination was noted in 5% of patients [11]. In a prospective study following 343 Japanese patients, transient worsening was observed in 1% of patients and the response to treatment was favourable [12].…”

“…Studies of SARS-CoV-2 vaccination in patients with established diagnosis of MG suggest that it might rarely lead to disease worsening [11,12]. In a retrospective study on an Italian cohort of 80 patients, transient worsening after vaccination was noted in 5% of patients [11].…”

SARS-CoV-2 vaccination and new-onset myasthenia gravis: A report of 7 cases and review of the literature

“…The literature so far suggests there may be a 1-15% risk of exacerbation of pre-existing MG following SARS-CoV-2 vaccination, mostly mild and responding well to standard treatment, with the exception of one published case of a patient who suffered a myasthenic crisis one week after the second dose of the Moderna vaccine [ 18 , [39] , [40] , [41] , [42] ].…”

“…Several vaccines including influenza, hepatitis B, human papilloma virus (HPV), and Bacillus Calamette-Geurin have been implicated in new onset MG or exacerbation of already established MG [5] , [6] , [7] , [8] , [9] , [10] , [11] , [12] , [13] . Molecular mimicry has been postulated as a possible mechanism with HPV L1 but this does not necessarily explain the mechanisms associated with other vaccination-induced cases [13] .…”

Clinical and Molecular Characterization of a Rare Case of BNT162b2 mRNA COVID-19 Vaccine-Associated Myositis

“…Furthermore, a recent case study reported that the BNT162b2 vaccine induced the development of acute transverse myelitis followed by fatal neurological complications [ 18 ]. A few cases have been reported for BNT162b2 vaccine-induced myasthenia gravis (MG) development, a chronic autoimmune condition affecting the neuromuscular junction [ 19 , 20 , 21 ]. However, some studies demonstrated that BNT162b2 vaccination showed overall good short-term safety in MG patients [ 22 , 23 ].…”