New-Onset Myasthenia Gravis Associated with SARS-CoV-2 Infection: A Systematic Review

Area of Science:

• Neurology
• Infectious Diseases
• Immunology

Background:

• Myasthenia gravis (MG) is a rare autoimmune disorder affecting neuromuscular junctions.
• The emergence of de novo autoimmune conditions following viral infections is a growing area of research.
• SARS-CoV-2 infection has been anecdotally linked to new-onset neurological disorders.

Purpose of the Study:

• To systematically review and synthesize data on de novo myasthenia gravis (MG) following SARS-CoV-2 infection.
• To characterize the clinical presentation, immunological features, temporal aspects, management, and outcomes of MG post-COVID-19.
• To address the research question regarding the specific characteristics of de novo MG in the context of SARS-CoV-2.

Main Methods:

• Systematic literature review adhering to PRISMA 2020 guidelines.
• Inclusion of published case reports and case studies detailing de novo MG after confirmed SARS-CoV-2 infection.
• Analysis of 44 studies encompassing 48 patient cases.

Main Results:

• De novo MG associated with COVID-19 typically manifested with a short median latency of 21 days post-infection.
• The majority of patients exhibited generalized onset and tested positive for acetylcholine receptor antibodies (AChR-Abs).
• Myasthenic crisis, ICU admission, and respiratory failure were common, yet most patients responded favorably to conventional MG therapies.

Conclusions:

• De novo myasthenia gravis following SARS-CoV-2 infection shares clinical and immunological similarities with classical MG, particularly AChR-Abs positivity.
• While severe manifestations like myasthenic crisis can occur, prompt treatment with standard therapies appears effective.
• Further research is warranted to elucidate the precise pathophysiological mechanisms linking SARS-CoV-2 to MG development.