SUBACUTE THYROIDITIS FOLLOWING SARS-COV-2 VACCINATION: AN AUTOIMMUNE/INFLAMMATORY SYNDROME INDUCED BY ADJUVANTS (ASIA SYNDROME).

Context: Subacute thyroiditis, a manifestation of Autoimmune/inflammatory syndrome induced by adjuvants that may develop after vaccination.

Objective: The aim of this study is to determine the importance of vaccination against COVID-19 in the etiology of subacute thyroiditis.

Design: This case reports/series is an observational, descriptive research design.

Subjects and methods: Five of the thirty patients who applied to our clinic with subacute thyroiditis in the last 6 months had a history of inactivated and mRNA vaccines in the last four weeks, after exclusion of infection and comorbidities. We present three cases of mRNA-based vaccination and two cases of inactive SARS-CoV-2 vaccination that met ASIA criteria.

Results: Our findings suggest that subacute thyroiditis may be a complication of vaccination against COVID-19.

Conclusion: Vaccine administration may led to autoimmune manifestation induction as well as autoantibody production. Adjuvant-induced autoimmune/inflammatory syndrome, an abnormal autoimmune response as a result of exposure to an adjuvant such as vaccine, appears likely in our cases.