New-Onset Myasthenia Gravis Confirmed by Electrodiagnostic Studies After a Third Dose of SARS-CoV-2 mRNA-1273 Vaccine

Neuromuscular diseases associated with COVID-19 vaccines: a systematic review and pooled analysis of 258 patients

BACKGROUND

Neuromuscular diseases (NMD) emerged as one of the main side effects of the COVID-19 vaccination. We pooled and summarized the evidence on the clinical features and outcomes of NMD associated with COVID-19 vaccination.

METHODS

We comprehensively searched three databases, Medline, Embase, and Scopus, using the key terms covering "Neuromuscular disease" AND "COVID-19 vaccine", and pooled the individual patient data extracted from the included studies.

RESULTS

A total of 258 NMD cases following COVID-19 have been reported globally, of which 171 cases were Guillain-Barré syndrome (GBS), 40 Parsonage-Turner syndrome (PTS), 22 Myasthenia Gravis (MG), 19 facial nerve palsy (FNP), 5 single fiber neuropathy, and 1 Tolosa-Hunt syndrome. All (100%) SFN patients and 58% of FNP patients were female; in the remaining NMDs, patients were predominantly male, including MG (82%), GBS (63%), and PTS (62.5%). The median time from vaccine to symptom was less than 2 weeks in all groups. Symptoms mainly appeared following the first dose of vector vaccine, but there was no specific pattern for mRNA-based.

CONCLUSION

COVID-19 vaccines might induce some NMDs, mainly in adults. The age distribution and gender characteristics of affected patients may differ based on the NMD type. About two-thirds of the cases probably occur less than 2 weeks after vaccination.

Clinical features and outcomes of Myasthenia Gravis associated with COVID-19 vaccines: A systematic review and pooled analysis

BACKGROUNDS

Myasthenia Gravis (MG), a chronic neuromuscular junction disorder, emerged as one of the serious side effects of the Coronavirus Disease 2019 (COVID-19) vaccination. We aimed to summarize the findings of studies on the clinical features and outcomes of COVID-19 vaccination-associated MG.

METHODS

We performed a systematic search on 3 databases, Medline, Embase, and Scopus, using the query "COVID-19 vaccine" and "Myasthenia Gravis." Patients' data, including clinical data, MG subtype, vaccine type, and vaccine dose number, were extracted from the eligible studies.

RESULTS

A total of 20 COVID-19 vaccination-related MGs have been reported worldwide. The median (interquartile range) age was 64 (51, 75) years; 85% (17/20) of them were male, and 70% (14/20) of patients had received messenger RNA-based vaccines. The most common symptoms, in order of frequency, were binocular diplopia (8/11) and ptosis (4/11); the median (interquartile range) time from vaccine to MG symptoms was 6 (2, 7.5) days. Repetitive nerve stimulation showed abnormal decrement in 85% (11/13) of patients, and all 4 patients getting single-fiber electromyography showed an abnormal finding. Nine out of twelve patients with data on clinical outcomes experienced partial/complete improvement of symptoms within 1 month.

CONCLUSION

MG cases after the COVID-19 vaccine are more likely to occur among males and adults older than 50 years. Our pooled cohort data suggest MG symptoms appear within 2 weeks after receiving the vaccine. The presenting symptoms in MG cases associated with COVID-19 vaccine are possibly similar to non-vaccination related MGs. Most patients are expected to experience partial/complete improvement within 1 month.

COVID-19 Vaccination and Late-Onset Myasthenia Gravis: A New Case Report and Review of the Literature

Myasthenia gravis (MG) is a rare autoimmune disease that is potentially threatening for patient life. Auto-antibodies targeting structures of the neuromuscular junction, particularly the acetylcholine receptor (AchR), are often found in the serum of MG patients. New-onset MG after SARS-CoV-2 vaccination has rarely been reported since the introduction of vaccination. Infections and COVID-19 infection have also been reported as possible triggers for a myasthenic crisis. We report a case of new-onset MG after receiving the mRNA COVID-19 vaccination. The patient was a 73-year-old male initially presenting with ocular symptoms and a rapid generalization. We also performed a literature revision of 26 described cases of MG after SARS-CoV-2 immunization. The patients were a majority of males with generalized late-onset MG occurring after the first dose of vaccine, similar to our patient. Only our patient showed a thymoma. Thymic mass and the positivity of AchR antibodies suggest that vaccination might have triggered a subclinical pre-existing MG with symptoms flaring. Clinicians should be aware of possible new-onset MG after COVID-19 vaccination, particularly in at-risk patients. Even though COVID-19 vaccination should be recommended in MG patients, particularly in well-compensated patients. However, more studies need to be performed in the future.

The safety of COVID-19 vaccines in patients with myasthenia gravis: A scoping review

Background

COVID-19 vaccines are required for individuals with myasthenia gravis (MG), as these patients are more likely to experience severe pneumonia, myasthenia crises, and higher mortality rate. However, direct data on the safety of COVID-19 vaccines in patients with MG are lacking, which results in hesitation in vaccination. This scoping was conducted to collect and summarize the existing evidence on this issue.

Methods

PubMed, Cochrane Library, and Web of Science were searched for studies using inclusion and exclusion criteria. Article titles, authors, study designs, demographics of patients, vaccination information, adverse events (AEs), significant findings, and conclusions of included studies were recorded and summarized.

Results

Twenty-nine studies conducted in 16 different countries in 2021 and 2022 were included. Study designs included case report, case series, cohort study, cross-sectional study, survey-based study, chart review, and systemic review. A total of 1347 patients were included. The vaccines used included BNT162b2, mRNA-1273, ChAdOx1 nCoV-19, inactivated vaccines, and recombinant subunit vaccines. Fifteen case studies included 48 patients reported that 23 experienced new-onset, and five patients experienced flare of symptoms. Eleven other types of studies included 1299 patients reported that nine patients experienced new-onset, and 60 participants experienced flare of symptoms. Common AEs included local pain, fatigue, asthenia, cephalalgia, fever, and myalgia. Most patients responded well to treatment without severe sequelae. Evidence gaps include limited strength of study designs, type and dose of vaccines varied, inconsistent window of risk and exacerbation criteria, limited number of participants, and lack of efficacy evaluation.

Conclusion

COVID-19 vaccines may cause new-onset or worsening of MG in a small proportion of population. Large-scale, multicenter, prospective, and rigorous studies are required to verify their safety.