New Onset Generalized Myasthenia Gravis Evolving Following SARS-CoV-2 Infection

Abstract

During the SARS-CoV-2 (COVID-19) pandemic, the immunogenicity of the virus for various autoimmune complications has been observed. To date, a few reports have been published that raise the possibility of new onset myasthenia gravis (MG) associated with COVID-19 infection. We report a case of a 65-year-old male who developed his initial myasthenic presentation with mild dysarthria 14 days after COVID-19 infection symptomatic onset. His bulbar symptoms, diplopia, and ptosis progressed considerably over the next 1.5 months before he was diagnosed with non-thymomatous MG. Serological tests showed a high concentration of anti-acetylcholine receptor and anti-titin antibodies. He responded well to treatment with pyridostigmine and intravenous immunoglobulin. Reasonable latency from COVID-19 infection and gradual evolvement of myasthenic symptoms makes the causative association probable in this case. To our knowledge, this is the first report of anti-titin antibodies in new-onset MG associated with COVID-19 infection. In the article, we analyze the previously reported cases and summarize the information published to date. We discuss the possible immunological mechanisms behind new onset autoimmune disease following a viral infection and the associated features that raise the suspicion for such a possibility. We also hint at structural homologies between SARS-CoV-2 spike glycoprotein and titin epitopes.