New onset and flare of rheumatic diseases following COVID-19 vaccination are mild and respond well to treatment: 9-month follow-up data from a single centre cohort.

OBJECTIVES: Anti-COVID-19 vaccines have proved to be effective and well tolerated. Great attention is now being paid to the characterisation of possible adverse events associated to their administration. We report a case series of suspected rheumatic diseases (RDs) following anti-COVID-19 vaccination. METHODS: We included patients evaluated at first-aid rheumatologic consultancy and at rheumatologic outpatient and inpatient clinic at Padova University Hospital between May and September 2021 presenting with a RD within 30 days after an anti-COVID-19 vaccine dose. Our selection was in accordance with the World Health Organisation guidelines for adverse event following immunisation (AEFI) surveillance. Patients were regularly re-evaluated by telemedicine or face-to-face visit. RESULTS: We identified 30 cases of RD following vaccination: 24 (80.0%) new onsets and 6 (20.0%) flares. Most of patients (76.6%) received the BNT162b2 vaccine. The mean time to RD onset/flare was 12±9 days. The most common manifestations were inflammatory arthritis (40.0%), rheumatic polymyalgia (33.3%) and adult-onset Still's disease (13.3%). At the last FU visit (9.6±2.2 months), 83.3% of patients showed complete response to first- or second-line therapy, 13.3% a partial response and one patient (3.3%) was still experiencing an active disease. CONCLUSIONS: Considering the amount of vaccine doses administered during the evaluation period we overall detected a limited number of cases. We noted a clear prevalence of autoinflammatory conditions and seronegative manifestations. The great majority of patients had mild features and showed a good response to therapy.

Frequency and clinical correlates of antiphospholipid antibodies arising in patients with SARS-CoV-2 infection: findings from a multicentre study on 122 cases

OBJECTIVES: COVID-19 features include disseminated intravascular coagulation and thrombotic microangiopathy indicating a hypercoagulable state. We aimed to investigate antiphospholipid antibodies (aPL) prevalence and clinical relationships in a large cohort of COVID-19 patients. METHODS: We analysed the prevalence and titres of serum aPL in 122 patients with COVID-19 and 157 with primary antiphospholipid syndrome (PAPS) and 91 with other autoimmune rheumatic diseases (oARD) for comparison. IgG/IgM anticardiolipin (aCL) and IgG/IgM anti-beta2glycoprotein I (β2GPI) were assayed using homemade ELISA, IgA aCL and anti-β2GPI by commercial ELISA kits and lupus anticoagulant (LAC) by multiple coagulation tests following updated international guidelines. RESULTS: Prevalence of IgG and IgM aCL and of IgG and IgM anti-β2GPI across COVID-19 patients were 13.4%, 2.7%, 6.3% and 7.1%, being significantly lower than in PAPS (p<0.0001 for all). Frequency of IgG aCL and IgM anti-β2GPI was comparable to oARD (13.4% vs. 13.2% and 7.1% vs. 11%, respectively), while IgG anti-β2GPI and IgM aCL were lower (p<0.01). IgA aCL and IgA anti-β2GPI were retrieved in 1.7% and 3.3% of COVID-19 patients, respectively. Positive LAC was observed in 22.2% COVID-19 vs. 54.1% of PAPS (p<0.0001) and 14.6% of oARD (p=0.21). Venous or arterial thromboses occurred in 18/46 (39.1%) COVID-19 patients and were not associated with positive aPL (p=0.09). CONCLUSIONS: Thrombosis is a frequent manifestation during COVID-19 infection. However, prevalence and titres of aPL antibodies or LAC were neither consistently increased nor associated with thrombosis when measured at a single timepoint, therefore not representing a suitable screening tool in the acute stage of disease.