A panel of international myasthenia gravis (MG) experts issued new evidence-based recommendations for the management of MG, including updated guidelines for thymectomy and medical management. The international consensus was published in Neurology.
A task force appointed by the Myasthenia Gravis Foundation of America included an international panel of MG experts that reviewed the 2016 consensus-based guidelines for managing MG. They then developed new and updated recommendations based on the latest findings in the literature.
The consensus guidelines provide a list of drugs that should be avoided or used with caution in patients with MG due to possible worsening of MG. That list included aminoglycoside, fluoroquinolone and macrolide antibiotics, beta blockers, botulinum toxin, chloroquine and hydroxychloroquine, deferoxamine and procainamide.
Thymectomy early in the disease should be considered in patients with generalized MG who are between 18 and 50 years old and have antibodies to acetylcholine receptors (AChR) to improve clinical outcome and reduce the need for immunotherapy and hospitalization for exacerbations to reduce. Surgical intervention should be considered if immunotherapy is ineffective or unbearable. The operation should be performed when the patient is stable.
Immunosuppressants are the recommended treatment for eye MG in patients with ophthalmoparesis or ptosis and functionally limiting or disruptive symptoms. Low-dose corticosteroids can be effective, but steroid-sparing immunosuppressants may be required if corticosteroids alone are ineffective, contraindicated, or not tolerated.
Similar to the 2016 consensus guideline, rituximab should be considered early in patients with MG and muscle-specific kinase antibodies with an unsatisfactory response to initial immunotherapy and may be considered when other immunosuppressants are ineffective or intolerable.
In patients with generalized MG, oral methotrexate can be used when other steroid-sparing agents, better supported by randomized controlled trial data, are ineffective or intolerable.
Eculizumab should be considered in patients with severe, refractory, generalized MG with antibodies against AChR.
While a diagnosis of MG is not an absolute contraindication to the use of immune checkpoint inhibitors, the risk of MG and other immune-mediated neurological complications should be discussed when this treatment is considered and close monitoring is required. Early aggressive treatment with high-dose steroids in combination with plasma exchange or intravenous immunoglobulin may be required in patients who develop overt MG on immune checkpoint inhibitors.
The experts concluded that this consensus “continues to be a living document that needs to be regularly reviewed and updated to reflect new information relevant to MG management.”
Narayanaswami P., Sanders DB, Wolfe G. et al. International Consensus Guidelines for the Management of Myasthenia Gravis: 2020 update. Neurology. 2021; 96 (3): 114-100. 122. doi: 10.1212 / WNL.0000000000011124