20.500.12556/RUL-189877 Disease relapse rate in children with autoimmune rheumatic diseases after COVID-19 infection and vaccination Background Paediatric patients with autoimmune rheumatic diseases (pARD) are often immunocompromised because of the disease and/or the therapy they receive. At the beginning of COVID-19 pandemic there was a greatconcern about the possibility of severe SARS-CoV-2 infection in these patients. The best method of protection is vaccination, so as soon as vaccine was licenced, we aimed to vaccinate them. Data on disease relapse rate after COVID-19 infection and vaccination are scarce, but they play important role in everyday clinical decisions. Methods The aim of this study was to determine the relapse rate of autoimmune rheumatic disease (ARD) after COVID-19 infection and vaccination. Data on demographic, diagnosis, disease activity, therapy, clinical presentation of the infection and serology were collected from pARD who had COVID-19 and from pARD who were vaccinated against COVID-19, from March 2020 to April 2022. All vaccinated patients received two doses of the BNT162b2 BioNTech vaccine, on average, 3.7 (S.D.=1.4) weeks apart. Activity of the ARD was followed prospectively. Relapse was defined as a worsening of the ARD in a time frame of 8 weeks after infection or vaccination. For statistical analysis, Fisher’s exact test and Mann-Whitney U test were used. Results We collected data from 115 pARD, which we divided into two groups. We included 92 pARD after infection and 47 after vaccination, with 24 in both groups (they were infected before/after vaccination). In 92 pARD we registered 103 SARS-CoV-2 infections. Infection was asymptomatic in 14%, mild in 67% and moderate in 18%, 1% required hospitalization; 10% had a relapse of ARD after infection and 6% after vaccination. There was a trend towards higher disease relapse rate after infection compared to vaccination, but the difference was not statistically significant (p=0.76). No statistically significant difference was detected in the relapse rate depending on the clinical presentation of the infection (p=0.25) or the severity of the clinical presentation of COVID-19 between vaccinated and unvaccinated pARD (p=0.31). Conclusions There is a trend towards a higher relapse rate in pARD after infection compared to vaccination and connection between the severity of COVID-19 and vaccination status is plausible. Our results were, however, not statistically significant. inflammatory multisystem syndrome acute respiratory syndrome COVID-19 child true false true Angleški jezik Ni določen Članek v reviji 2026-10-17 09:55:48 2026-10-19 09:47:18 2026-10-23 09:27:50 0000-00-00 00:00:00 2023 0 0 8 str. no. 46 Vol. 21 2023 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 61 1546-0096 10.1186/s12969-023-00829-4 159185667 RAZ_Sinkovec_Savsek_Tjasa_2023.pdf RAZ_Sinkovec_Savsek_Tjasa_2023.pdf 1 154464FF1A655D19567440179131B8A4 d23c9c67364cc8c67f90d81138fcbdf3cc0375051f3f3d3d92902d55dda5420b 4f5150f6-cb91-11f1-8bc5-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=250874 https://link.springer.com/article/10.1186/s12969-023-00829-4 0 3708b313-cb91-11f1-8bc5-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=250873 Medicinska fakulteta 0 0 0