COVID-19 Vaccine-Induced Autoimmune Hyperthyroidism of Graves' disease

Avaniyapuram Kannan Murugan, M.Phil., Ph.D.^*Ali S Alzahrani

• King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia

Graves' disease (GD) is an autoimmune condition that results in hyperthyroidism, in which the immune system wrongly targets the thyroid gland, causing it to produce an abnormally high amount of thyroid hormones. Genetic predisposition, environmental factors, such as infections, stress, disruptions in the gut microbiome, excessive iodine intake, and epigenetic changes, have all been implicated in the development of GD. The recent pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was a severe global crisis. The emergence of COVID-19 vaccines has been pivotal in combating the viral infection and its spread. However, reports of rare adverse events, including the development of autoimmune disorders such as GD following vaccination, have raised concerns. Autoimmune factors play a critical role in the pathogenesis of GD, including the production of autoantibodies targeting the thyroid gland. In this review, the reported cases were critically analyzed to elucidate commonalities and potential triggers for developing this autoimmune disorder. We explore the vital role of autoimmune factors in inducing GD. We also discuss the molecular mechanisms underlying vaccine-induced autoimmunity, particularly the antigen presentation, bystander activation, molecular mimicry, and induction of inflammatory factors following vaccination. Understanding the mechanisms underlying COVID-19 vaccine-induced GD may significantly improve patient management and guide vaccination strategies.