Effects of anti-SARS-CoV-2 vaccination on safety and disease exacerbation in patients with Behcet syndrome in a monocentric cohort

Aim Vaccination represents a cornerstone in mastering the coronavirus disease 2019 (COVID-19) pandemic. There is a paucity of data regarding the safety of COVID-19 vaccines in patients with rheumatic diseases such as Behcet syndrome (BS). The present study aimed to investigate the side-effects and post-vaccine disease exacerbation rates of COVID-19 vaccines in a BS cohort. Methods We retrospectively evaluated 450 BS patients followed in our clinic who met the criteria of the International Study Group. COVID-19 vaccination status, type of vaccine received (Pfizer-BioNTech vs CoronaVac), post-vaccine side-effects and exacerbations were evaluated by interviewing patients over the phone or face to face. Behcet's Disease Current Activity Form (BDCAF) scores were calculated for BS symptoms before and after vaccination. Results In all, 287 patients received at least one dose of the COVID-19 vaccine. Of the total number of COVID-19 vaccines (n = 639), 379 (59%) were Pfizer-BioNTech vaccines and 257 (41%) were CoronaVac vaccines. The number of side-effects after first, second, third and fourth vaccine doses were 151 (52.6%), 135 (49.4%), 29 (42.6%), and 3 (30%), respectively. BS exacerbation after first, second, third, and fourth vaccine doses were 151 (52.6%), 135 (49.4%), 16 (23.5%), and 3 (30%), respectively. Injection site pain/swelling was the most common side-effect at all vaccine doses followed by fatigue and arthralgia. Conclusion COVID-19 vaccines are well tolerated in patients with BS, and more side-effects develop after mRNA vaccines. Regardless of the vaccine type, exacerbations after the COVID-19 vaccine are common, predominantly mucocutaneous and articular involvement, and exacerbations in the form of other organ involvement are rare.