Autoimmune phenomena following SARS-CoV-2 vaccination.

• Israel undertook large scale COVID-19 vaccination with the BNT162b2 mRNA vaccine. • We describe several cases of autoimmune phenomena among the recently vaccinated. • Patients with autoimmune diseases may experience flares post-vaccination. • Most patients experience only mild, self-limiting autoimmune events. • Progression to frank, chronic autoimmunity appears to be a rare occurrence. Vaccines represent an attractive possible solution to the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) pandemic. Widespread vaccine distribution has yet to occur in most countries, partially due to public concerns regarding possible side effects. While studies indicate the vaccine is exceptionally safe, rare systemic side effects remain possible. In Israel, where a large percentage of the population has been rapidly vaccinated, such adverse events may be more apparent. We report a series of patients presenting with de-novo or flares of existing autoimmune conditions associated with the Pfizer BNT162b2 mRNA SARS-CoV-2 vaccine. All patients were assessed in our tertiary care center in Israel and had no history of previous SARS-COV-2 infection. We observed that while immune phenomena may occur following vaccination, they usually follow a mild course and require modest therapy. We briefly expound on the theoretical background of vaccine related autoimmunity and explore future research prospects. [ABSTRACT FROM AUTHOR]