SARS-CoV-2 infection in patients with systemic autoimmune diseases.

Systemic autoimmune diseases (SAD) are a heterogeneous group of diseases with a common aetiopathogenic basis affecting all ages characterised by a systemic phenotypic expression with a wide range of severity and outcomes that often require immunosuppressive therapies, leaving patients at high risk of infection. Knowledge of the impact of COVID-19 in patients with SAD is limited because most are included in studies carried out in patients with autoimmune and rheumatic diseases (mainly inflammatory arthritis). Most studies supported an increased risk of SARS-Cov-2 infection in patients with AD and SAD. Although case-control studies reported no significant differences in the rate of poor outcomes between patients with and without AD, large population-based studies analysing baseline risk factors reported a 2-3 times higher rate of poor outcomes in patients with AD, especially in those with SAD. Individual risk factors associated with poor outcomes included gender male, older age, and underlying comorbidities and therapies (glucocorticoids, sulfasalazine, immunosuppressants and rituximab). Patients with SAD had less favourable COVID-19 outcomes than those with inflammatory arthritis, possibly due to a differentiated underlying therapeutic approach (glucocorticoids, immunosuppressants and B-cell depleting agents for most SAD, anti-cytokine therapies and JAK inhibitors for inflammatory arthritis). Despite the limited evidence, most studies suggest that patients with SAD have an increased risk of a worse evolution of SARS-CoV-2 infection, including a greater risk of hospitalisation/ICU admission and worse survival rates and, therefore, should be considered a high-risk group for COVID-19.

Safety and efficacy of SARS-CoV-2 vaccination in 1237 patients with primary Sjögren syndrome.

OBJECTIVES: To investigate the safety and efficacy of SARS-Cov-2 vaccination in patients with primary Sjögren syndrome (pSS) due to scarcity of data in this population. METHODS: By the first week of May 2021, all Big Data SS Consortium centres patients who had received at least one dose of any SARS-CoV-2 vaccine were included in the study. The in-charge physician asked patients about local and systemic reactogenicity to collect SARS-CoV-2 vaccination data. RESULTS: The vaccination data of 1237 patients were received. A total of 835 patients (67%) reported any adverse events (AEs), including local (53%) and systemic (50%) AEs. Subjective symptoms (63%) were the most common local AEs, followed by objective signs at the injection site (16%), and general symptoms were the most commonly reported systemic AEs (46%), followed by musculoskeletal (25%), gastrointestinal (9%), cardiopulmonary (3%), and neurological (2%). In addition, 141 (11%) patients reported a significant worsening/exacerbation of their pre-vaccination sicca symptoms and fifteen (1.2%) patients reported active involvement in the glandular (n=7), articular (n=7), cutaneous (n=6), pulmonary (n=2), and peripheral nervous system (n=1) domains due to post-vaccination SS flares. In terms of vaccination efficacy, breakthrough SARS-CoV-2 infection was confirmed after vaccination in three (0.24 %) patients, and positive anti-SARS-Cov-2 antibodies were detected in approximately 95% of vaccinated SS patients, according to data available. CONCLUSIONS: Our data suggest that patients with pSS develop adequate humoral response and no severe AEs after SARS-CoV-2 vaccination and therefore raise no concerns about the vaccine's efficacy or safety profile in this population.

Post-COVID-19 syndrome in patients with primary Sjögren's syndrome after acute SARS-CoV-2 infection.

OBJECTIVES: To analyse the frequency and characteristics of post-COVID-19 syndrome in patients with primary Sjögren's syndrome (pSS) affected by acute SARS-CoV-2 infection. METHODS: By the first week of April 2021, all centres included in the Big Data Sjögren Consortium were contacted asking for patients included in the Registry diagnosed with SARSCoV-2 infection according to the ECDC guidelines. According to the NICE definitions, symptoms related to COVID-19 were classified as acute COVID-19 (signs and symptoms for up to 4 weeks), ongoing symptomatic COVID-19 (presence of signs and symptoms from 4 to 12 weeks) and post-COVID-19 syndrome (signs and symptoms that continue for > 12 weeks not explained by an alternative diagnosis after a protocolized study). RESULTS: We identified 132 patients who were followed a mean follow-up of 137.8 days (ranging from 5 days to 388 days) after being diagnosed with COVID-19. In the last visit, 75 (57%) patients remained symptomatic: 68 (52%) remained symptomatic for more than 4 weeks fulfilling the NICE definition for ongoing symptomatic post-COVID-19, and 38 (29%) remained symptomatic for more than 12 weeks fulfilling the definition of post-COVID-19 syndrome. More than 40% of pSS patients reported the persistence of four symptoms or more, including anxiety/depression (59%), arthralgias (56%), sleep disorder (44%), fatigue (40%), anosmia (34%) and myalgias (32%). Age-sex adjusted multivariate analysis identified raised LDH levels (OR 10.36), raised CRP levels (OR 7.33), use of hydroxychloroquine (OR 3.51) and antiviral agents (OR 3.38), hospital admission (OR 8.29), mean length of hospital admission (OR 1.1) and requirement of supplemental oxygen (OR 6.94) as factors associated with a higher risk of developing post-COVID-19 syndrome. A sensitivity analysis including hospital admission in the adjusted model confirmed raised CRP levels (OR 8.6, 95% CI 1.33-104.44) and use of hydroxychloroquine (OR 2.52, 95% CI 1.00-6.47) as the key independent factors associated with an enhanced risk of developing post-COVID-19 syndrome. CONCLUSIONS: This is the first study that analyses the frequency and characteristics of post-COVID-19 syndrome in patients affected by a systemic autoimmune disease. We found that 57% of patients with pSS affected by COVID-19 remain symptomatic after a mean follow-up of 5 months. The risk of developing post-COVID-19 syndrome in patients who required hospitalisation was 8-times higher than in non-hospitalised patients, with baseline raised CRP levels and the use of hydroxychloroquine being independent risk factors for post-COVID-19.

Haemophagocytic syndrome and COVID-19.

Primary and secondary haemophagocytic lymphohistiocytosis (HLH) are hyperferritinaemic hyperinflammatory syndromes with a common terminal pathway triggered by different etiopathogenetic factors. HLH is characterised by a decreased capacity of interferon gamma production with an activated NK phenotype profile similar to other hyperinflammatory syndromes. Viruses are closely linked to the development of HLH as infectious triggers, and the break of tolerance to self-antigens is considered a critical mechanism involved in the development of immune-mediated conditions triggered by viral infections. Emerging studies in patients with COVID-19 are suggesting a key role of monocytes/macrophages in the pathogenesis of this viral infection, and there is a significant overlap between several features reported in severe COVID-19 and the features included in the HLH-2004 diagnostic criteria. Therefore, SARS-Cov-2, as other respiratory viruses, may also be considered a potential etiological trigger of HLH. The frequency of HLH in adult patients with severe COVID-19 is lower than 5%, although this figure could be underestimated considering that most reported cases lacked information about some specific criteria (mainly the histopathological criteria and the measurement of NK cell function and sCD25 levels). Because HLH is a multi-organ syndrome, the diagnostic approach in a patient with severe COVID-19 in whom HLH is suspected must be carried out in a syndromic and holistic way, and not in the light of isolated clinical or laboratory features. In COVID-19 patients presenting with persistent high fever, progressive pancytopenia, and hepatosplenic involvement, together with the characteristic triad of laboratory abnormalities (hyperferritinaemia, hypertriglyceridaemia, and hypofibrinogenaemia), the suspicion of HLH is high, and the diagnostic workup must be completed with specific immunological and histopathological studies.