It was suggested that all SARS-CoV2 infections lead to development of specific IgG antibodies that remain detectable in time. Targeted Immune-Modulating Therapies (TIMT) for treatment of Immune Mediated Inflammatory diseases (IMID) could interfere with humoral immune response against COVID19. To investigate the seroprevalence of SARS-CoV2 IgG in relation to previous exposure to COVID19 and ongoing IMID treatment a cross-disciplinary, prospective observational cohort was set up at two Belgian university hospitals. Between 17/12/2020 and 28/02/2021, patients with IMIDs of the skin (psoriasis (PsO), hidradenitis suppurativa (HS), atopic dermatitis (AD)), gut or joints were asked to participate. Patients under conventional systemic treatment or TIMT were included. An electronic survey (REDCap®) and blood samples were obtained (SARS-CoV-2IgG Abbott–Architect kit®). Statistical analyses were performed with SPSS26. 2166 IMID patients consented to take part. 1913 completed the survey: 218 dermatology patients (77% PsO, 12% HS, 11% AD), 415 rheumatology and 1217 IBD patients. 372 patients (19.5%) reported having experienced symptoms suggestive of COVID19: fatigue (61.3%) and headache (48.1%) were most frequent. 96 patients (5.04%) had a positive SARS-CoV2 PCR test on nasal or throat swab: in 45.8% anti-SARS-CoV2 IgG seroconversion was confirmed. There was no significant difference in seroconversion rate between the 2 treatment groups (P=0.192). Of the seroconverted group, 75.0% were treated with TIMT. Prevalence of COVID19 symptoms and number of confirmed COVID19 cases remain low in this IMID cohort, regardless of treatment modality. There was no significant difference in SARS-CoV2 IgG seroconversion rate between TIMT and conventional systemic treatment in patients with positive PCR.

ESDR067 - BELCOMID: BELgian Cohort study of COVID-19 in Immune Mediated Inflammatory Diseases

50th Annual Meeting of the European Society for Dermatological Research. VIRTUAL MEETING