COVID-19 infection has been shown to increase the risk of new-onset myasthenia gravis (MG), myasthenic crisis, respiratory failure, and mortality rates, all due to the presence of a cytokine storm in these individuals, according to a new study published in the Egyptian Journal of Neurology. Some experimental treatments used in patients with MG can worsen symptoms of the disease as well.

A systematic review on the subject was conducted and the study inclusion criteria for this review were full-text manuscripts that reported on the relationship between COVID-19 and MG, as well as primary studies of every design. All of the articles selected had been published in English between January 2000 and October 2021. All studies that were chosen also needed to use humans as the subject.

Recognizing that viral infections can exacerbate and/or worsen neurologic disorders caused by autoimmune etiology, the researchers sought to evaluate the association between MG and COVID-19. They applied a systematic literature finding in 15 electronic scientific resources and assessed the study quality and risk for bias of each of the articles retrieved.

Read more about MG epidemiology

MG is a neurologic autoimmune disorder caused by autoantibodies that form against the nicotinic acetylcholine receptor (nAChR). Blockade and downregulation of nAChR decrease nerve impulses that can generate muscle action potentials.

Individuals with MG who contract COVID-19 are at an increased risk for a poor outcome because of their immunocompromised status from the use of immunosuppressant therapy, dysregulation of their immune system, respiratory muscle weakness, and respiratory failure due to pneumonia or pulmonary thromboembolism.

A total of 352 peer-reviewed studies were identified from electronic records and an additional 10 studies were found through other search engines. Following the removal of duplicates, 200 studies were screened for eligibility, with 22 ultimately included in the current review.

“The management of COVID-19 patients with MG is tailored to each person and based on national guidelines and local expert recommendations,” the researchers said. They concluded that additional research is warranted with a “larger sample size with diverse demographic variances and longer follow-up time.”

Reference

Tugasworo D, Kurnianto A, Retnaningsih, Andhitara Y, Ardhini R, Budiman J. The relationship between myasthenia gravis and COVID-19: a systematic review. Egypt J Neurol Psychiatr Neurosurg. 2022;58(1):83. doi:10.1186/s41983-022-00516-3