A growing body of evidence indicates that patients with cardiovascular complications are at a higher risk for developing severe Coronavirus Disease 2019 (COVID‐19) (1). In addition, the high incidence of thromboembolic events suggests an important role of COVID‐19‐induced coagulopathy (2). Antiphospholipid autoantibodies (aPL), that are essential markers for antiphospholipid syndrome, are considered as a cardiovascular risk factor.

Persistence of various symptoms in patients who have recovered from coronavirus disease 2019 (COVID-19) was recently defined as ‘long COVID’ or ‘post-COVID syndrome’ (PCS). This article reports a case of a 58-year-old woman who, although recovering from COVID-19, had novel and persistent symptoms including neurological complications that could not be explained by any cause other than PCS. In addition to a low inflammatory response, persistence of immunoglobulin G anticardiolipin autoantibody positivity and eosinopenia were found 1 year after acute COVID-19 infection, both of which have been defined previously as independent factors associated with the severity of COVID-19. The pathophysiological mechanism of PCS is unknown, but the possibility of persistence of the virus, especially in the nervous system, could be suggested with a post-infectious inflammatory or autoimmune reaction.

The TWEAK/Fn 14 pathway is now well known for its involvement in the modulation of inflammation in various human autoimmune/chronic inflammatory diseases (AICID) including lupus, rheumatoid arthritis and multiple sclerosis. A panel of data is now available concerning TWEAK expression in tissues or biological fluids of patients suffering from AICID, suggesting that it could be a promising biological marker in these diseases. Evidences from several teams support the hypothesis that blocking TWEAK/fn14 pathway is an attractive new therapeutic lead in such diseases and clinical trials with anti-TWEAK blocking antibodies are in progress. In this mini-review we discuss the potential use of TWEAK quantification in AICD management in routine practice and highlight the challenge of standardizing data collection to better estimate the clinical utility of such a biological parameter.

Whereas the detection of antiphospholipid autoantibodies (aPL) in COVID-19 is of increasing interest, their role is still unclear. We analyzed a large aPL panel in 157 patients with COVID-19 according to the disease severity. We also investigated a potential association between aPL and extracellular DNA (exDNA, n = 85) or circulating markers of neutrophil extracellular traps (NET) such as citrullinated histones H3 (CitH3, n = 49). A total of 157 sera of patients infected by SARS-CoV-2 were collected. A large aPL panel including lupus anticoagulant, anti-cardiolipin and anti-beta-2 glycoprotein I (IgG, IgM and IgA), anti-phosphatidylethanolamine IgA, anti-prothrombin (IgG and IgM) was retrospectively analyzed according to the disease severity. We found a total aPL prevalence of 54.8% with almost half of the cases having aCL IgG. Within an extended panel of aPL, only aCL IgG were associated with COVID-19 severity. Additionally, severe patients displayed higher CitH3 levels than mild patients. Interestingly, we highlighted a significant association between the levels of aCL IgG and exDNA only in aCL positive patients with severe disease. In conclusion, we showed a significant link between aPL, namely aCL IgG, and circulating exDNA in patients with severe form of COVID-19, that could exacerbate the thrombo-inflammatory state related to disease severity.