Comparative analysis of synovial inflammation after SARS-CoV-2 infection

Examination of SARS-CoV-2 RNA in joint synovial fluid of patients with COVID-19 and acute knee arthritis

BACKGROUND

It has not yet been fully established that there is coronavirus disease 2019 (COVID-19) involvement in the synovial fluid and it remains a topic of debate.

OBJECTIVE

The aim of this study was to evaluate the presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in knee joint synovial fluid of patients with COVID-19.

METHODS

This retrospective study was conducted with an initial screening of patients who were admitted to a tertiary pandemic hospital due to COVID-19 symptoms, and underwent treatment for COVID-19 between March and June 2020.

RESULTS

A total of 2476 patients were hospitalized or received treatment for a possible diagnosis of COVID-19. While the RT-PCR test was positive in 318 patients (12.8%), 2158 (87.2%) were computed tomography positive but reverse transcription-polymerase chain reaction (RT-PCR) negative. Twelve patients were consulted due to acute joint effusion. Of five patients with knee joint effusion and a positive RT-PCR test, the synovial tissue RT-PCR test was positive in only one patient.

CONCLUSION

This paper is the first to show the presence of SARS-CoV-2 in synovial fluid. This can be considered of importance for the determination and elimination of the route of transmission, thereby preventing further development and spread of the disease.

Covid-19-related right hip monoarthritis: A case report and literature review

This article presents the case of a young patient with severe acute left hip pain who tested positive for COVID-19. The diagnostic approach and management are presented, followed by a review of the literature. This 11-year-old student was admitted for acute left hip pain of abrupt onset, inflammatory, evolving for 24 h in a febrile context with no change in general condition. The initial workup revealed a hyperleukocytosis in the blood count, CRP 198.52 mg/L, and a 95 mm SV. The pelvic X-ray was unremarkable, and the hip ultrasound showed synovial hypertrophy, with no effusion on Doppler examination. The situation worsened 24 h later with the onset of acute respiratory distress syndrome. The chest X-ray showed bilateral alveolar interstitial lung disease, and the CT scan showed hyperdensity and crazy paving. The COVID-19 RDT test on a nasopharyngeal sample came back positive, as did the RT-PCR. Death occurred a few hours later in acute respiratory distress. Our case is consistent with what has been reported in the literature, but requires further study on an international scale to better define the phenotype of the disease.

COVID-19 illness: Different comorbidities may require different immunological therapeutic targets

BACKGROUND

The SARS-CoV-2 pandemic has led to more than 6,870.000 deaths worldwide. Despite recent therapeutic advances, deaths in Intensive Care Units still range between 34 and 72%, comprising substantial unmet need as we move to an endemic phase. The general agreement is that in the first few days of infection, antiviral drugs and neutralizing monoclonal antibodies should be adopted. When the patient is hospitalized and develops severe pneumonia, progressing to a systemic disease, immune modifying therapy with corticosteroids is indicated. Such interventions, however, are less effective in the context of comorbidities (e.g., diabetes, hypertension, heart failure, atrial fibrillation, obesity and central nervous system-CNS diseases) which are by themselves associated with poor outcomes. Such comorbidities comprise common and some distinct underlying inflammatory pathobiology regulated by differential cytokine taxonomy.

METHODS

Searching in the PubMed database, literature pertaining to the biology underlying the different comorbidities, and the data from the studies related to various immunological treatments for the Covid-19 disease were carefully analyzed.

RESULTS

Several experimental and clinical data have demonstrated that hypertension and atrial fibrillation present an IL-6 dependent signature, whereas diabetes, obesity, heart failure and CNS diseases may exhibit an IL-1a/b predominant signature. Distinct selective cytokine targeting may offer advantage in treating severe COVID-19 illness based on single or multiple associated comorbidities. When the patient does not immediately respond, a broader target range through JAKs pathway inhibitors may be indicated.

CONCLUSIONS

Herein, we discuss the biological background associated with distinct comorbidities which might impact the SARS-CoV-2 infection course and how these should to be addressed to improve the current therapeutic outcome.

COVID-associated arthritis after severe and non-severe COVID-19: A systematic review

AIM

Since the coronavirus outbreak became a global health emergency in 2020, various immune-based effects, such as inflammatory arthritis (IA), have been recorded. This study aimed to determine the role of COVID-19 severity on post-COVID arthritis.

METHODS

We systematically reviewed 95 patients who developed arthritis after severe and non-severe COVID-19 infection by searching the databases, including PubMed, SCOPUS, and EMBASE. We used the term "COVID-associated arthritis" because there was no definite diagnostic method for classifying arthritides after COVID-19 infection, and the diagnosed arthritis types were based on the authors' viewpoints.

RESULTS

After evaluating the data between the two severe and non-severe COVID-19-infected groups of patients, the results showed that the COVID-19 severity may affect the pattern of joint involvement in IA. In both groups, combination therapy, including oral nonsteroidal anti-inflammatory drugs with different types of corticosteroids, was the most common treatment. In addition, the mean age and comorbidities rate was higher in the severe COVID-19 group. Even though the patients in the severe COVID-19 group developed more serious COVID-19 symptoms, they experienced milder arthritis with better outcomes and more delayed onsets that required less aggressive therapy.

CONCLUSION

We conclude that there may be an inverse relationship between COVID-19 severity and arthritis severity, possibly due to weaker immunity conditions following immunosuppressant treatments in patients with severe COVID-19.

Acute arthritis following SARS-CoV-2 infection: About two cases

Joint involvement in COVID-19 may occur at different stages of the disease and maybe represented by non-specific arthralgia or by acute arthritis. We report two cases of COVID-19 infection that were complicated by postviral reactive arthritis. Case 1: A 47-year-old male was presented 20 days after a COVID-19 infection with acute right knee arthritis. On biologic data, erythrocyte sedimentation rate and C-reactive protein were normal, and immunologic data were negative. A joint puncture was performed showing a turbid fluid. Testing for microcrystals was negative, as well as the synovial fluid culture. An infectious investigation was conducted, which was negative. The patient's complaints improved significantly, with analgesics and non-steroidal anti-inflammatory drugs (NSAID). Case 2: A 33-year-old female presented with acute left knee arthritis evolving for 48 h, free of fever, after a COVID-19 infection treated 15 days ago. On examination, besides knee arthritis, the osteoarticular examination was normal. A biological inflammatory syndrome was noted in laboratory tests. A yellow fluid with multiple PNN was detected in the joint fluid aspiration, with a negative culture. The patient was treated by analgesics and NSAID. The follow-up was highlighted by the arthritis resolution. Conclusion: Both of our cases are consistent with what has already been reported in the literature confirming the development of PostCOVID arthritis and strengthen the impending necessity of wider studies to identify rheumatologic manifestations in the short- and long-terms after surviving COVID-19.

Reactive arthritis occurring after COVID-19 infection: a narrative review

PURPOSE

Reactive arthritis is acute aseptic arthritis occurring 1 to 4 weeks after a distant infection in a genetically predisposed individual. It may occur after COVID-19 infection. We summarize, in this article, the current findings of reactive arthritis following COVID-19 infection.

METHODS

A literature search has been performed from December 2019 to December 2021. We included case reports of reactive arthritis occurring after COVID-19 infection. We collected demographic, clinical, and paraclinical data.

RESULTS

A total of 22 articles were reviewed. There were 14 men and 11 women with a mean age of 44.96 + 17.47 years. Oligoarticular involvement of the lower limbs was the most frequent clinical presentation. The time between arthritis and COVID infection ranged from 6 to 48 days. The diagnosis was based on clinical and laboratory findings. The pharmacological management was based on non-steroidal anti-inflammatory drugs in 20 cases. Systemic or local steroid therapy was indicated in 13 patients. Sulfasalazine was indicated in two cases. Alleviation of symptoms and recovery were noted in 22 cases. The mean duration of the clinical resolution was 16 + 57 days.

CONCLUSION

The diagnosis of reactive arthritis should be considered in patients with a new onset of arthritis following COVID-19 infection. Its mechanism is still unclear.

A case of de novo seronegative inflammatory oligoarthritis associated with COVID-19 infection

Infection with SARS-CoV-2 (COVID-19) virus is characterized by an acute respiratory viral illness, often accompanied by extrapulmonary manifestations. Musculoskeletal symptoms such as myalgias and arthralgias are observed in 60 - 70% of cases. Inflammatory arthritis associated with SARS-CoV-2 infection has been reported in the literature, however, nearly all such cases describe a post-viral or reactive phenomenon occurring a few weeks following the infection. We report a unique case of de novo arthritis at the onset of a confirmed COVID-19 infection in a 55-year-old woman. Magnetic resonance imaging demonstrated synovial enhancement consistent with synovitis. Her disease was deemed refractory after failing several immunosuppressive agents. Lastly, we compare our patient's clinical presentation with two other similar cases to understand the natural history of this emerging syndrome.

COVID-19 and the antiphospholipid syndrome

Coronavirus disease 2019 (COVID-19) has resulted in a global pandemic. Most COVID-19 patients are asymptomatic or have flu-like symptoms. However, around 15% of the patients may have severe disease, including unilateral or bilateral pneumonia with acute respiratory distress syndrome and progressive hypoxemia that may require mechanical ventilation assistance. A systemic inflammatory response syndrome occurs in the most severe forms of COVID-19, with multiorgan involvement which can be life threatening caused by a cytokine storm. Although what best characterizes COVID-19 are the manifestations of the respiratory system, it has been shown that it also acts at the cardiovascular level, producing coagulation abnormalities, which causes thrombotic events mainly in the arteries/arterioles, microcirculation and venous system, and potentially increased mortality risk. This multiorgan vascular disease overlaps with other known microangiopathies, such as thrombotic microangiopathy or paroxysmal nocturnal hemoglobinuria, where complement overactivation plays an important role in the pathophysiology of thrombosis. Furthermore, coagulopathy secondary to COVID-19 occurs in the context of an uncontrolled inflammatory response, reminiscent of APS, especially in its catastrophic form. This review summarizes the current knowledge regarding the relationship between COVID-19 and the APS.

Complement Regulation in Immortalized Fibroblast-like Synoviocytes and Primary Human Endothelial Cells in Response to SARS-CoV-2 Nucleocapsid Protein and Pro-Inflammatory Cytokine TNFα

Background: Case reports are available showing that patients develop symptoms of acute arthritis during or after recovery from SARS-CoV-2 infection. Since the interrelation is still unknown, our aim was to study the impact of the SARS-CoV-2 nucleocapsid protein (NP) on human fibroblast-like synoviocytes and human endothelial cells (hEC) in terms of complement and cytokine regulation. Methods: Non-arthritic (K4IM) synoviocyte, arthritic (HSE) synoviocyte cell lines and primary hEC were stimulated with recombinant NP and/or TNFα. Analyses of cell viability, proliferation, gene and protein expression of cytokines and complement factors were performed. Results: NP suppressed significantly the vitality of hEC and proliferation of HSE. NP alone did not induce any significant changes in the examined gene expressions. However, NP combined with TNFα induced significantly higher TNFα in HSE and K4IM as well as higher IL-6 and CD55 gene expression in HSE and suppressed C3aR1 gene expression in hEC. HSE proliferated twice as fast as K4IM, but showed significantly lesser gene expressions of CD46, CD55, CD59 and TNFα with significantly higher IL-6 gene expression. CD35 gene expression was undetectable in K4IM, HSE and hEC. Conclusions: NP might contribute in combination with other inflammatory factors to complement regulation in arthritis.

IFI44 is an immune evasion biomarker for SARS-CoV-2 and Staphylococcus aureus infection in patients with RA

Background

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused a global pandemic of severe coronavirus disease 2019 (COVID-19). Staphylococcus aureus is one of the most common pathogenic bacteria in humans, rheumatoid arthritis (RA) is among the most prevalent autoimmune conditions. RA is a significant risk factor for SARS-CoV-2 and S. aureus infections, although the mechanism of RA and SARS-CoV-2 infection in conjunction with S. aureus infection has not been elucidated. The purpose of this study is to investigate the biomarkers and disease targets between RA and SARS-CoV-2 and S. aureus infections using bioinformatics analysis, to search for the molecular mechanisms of SARS-CoV-2 and S. aureus immune escape and potential drug targets in the RA population, and to provide new directions for further analysis and targeted development of clinical treatments.

Methods

The RA dataset (GSE93272) and the S. aureus bacteremia (SAB) dataset (GSE33341) were used to obtain differentially expressed gene sets, respectively, and the common differentially expressed genes (DEGs) were determined through the intersection. Functional enrichment analysis utilizing GO, KEGG, and ClueGO methods. The PPI network was created utilizing the STRING database, and the top 10 hub genes were identified and further examined for functional enrichment using Metascape and GeneMANIA. The top 10 hub genes were intersected with the SARS-CoV-2 gene pool to identify five hub genes shared by RA, COVID-19, and SAB, and functional enrichment analysis was conducted using Metascape and GeneMANIA. Using the NetworkAnalyst platform, TF-hub gene and miRNA-hub gene networks were built for these five hub genes. The hub gene was verified utilizing GSE17755, GSE55235, and GSE13670, and its effectiveness was assessed utilizing ROC curves. CIBERSORT was applied to examine immune cell infiltration and the link between the hub gene and immune cells.

Results

A total of 199 DEGs were extracted from the GSE93272 and GSE33341 datasets. KEGG analysis of enrichment pathways were NLR signaling pathway, cell membrane DNA sensing pathway, oxidative phosphorylation, and viral infection. Positive/negative regulation of the immune system, regulation of the interferon-I (IFN-I; IFN-α/β) pathway, and associated pathways of the immunological response to viruses were enriched in GO and ClueGO analyses. PPI network and Cytoscape platform identified the top 10 hub genes: RSAD2, IFIT3, GBP1, RTP4, IFI44, OAS1, IFI44L, ISG15, HERC5, and IFIT5. The pathways are mainly enriched in response to viral and bacterial infection, IFN signaling, and 1,25-dihydroxy vitamin D3. IFI44, OAS1, IFI44L, ISG15, and HERC5 are the five hub genes shared by RA, COVID-19, and SAB. The pathways are primarily enriched for response to viral and bacterial infections. The TF-hub gene network and miRNA-hub gene network identified YY1 as a key TF and hsa-mir-1-3p and hsa-mir-146a-5p as two important miRNAs related to IFI44. IFI44 was identified as a hub gene by validating GSE17755, GSE55235, and GSE13670. Immune cell infiltration analysis showed a strong positive correlation between activated dendritic cells and IFI44 expression.

Conclusions

IFI144 was discovered as a shared biomarker and disease target for RA, COVID-19, and SAB by this study. IFI44 negatively regulates the IFN signaling pathway to promote viral replication and bacterial proliferation and is an important molecular target for SARS-CoV-2 and S. aureus immune escape in RA. Dendritic cells play an important role in this process. 1,25-Dihydroxy vitamin D3 may be an important therapeutic agent in treating RA with SARS-CoV-2 and S. aureus infections.

Reactive arthritis after SARS-CoV-2 infection

SARS-CoV-2 has been recognised as a potential trigger of inflammatory arthritis in individuals with inflammatory rheumatic diseases as well as in previously unaffected individuals. However, new-onset arthritis after COVID-19 is a heterogeneous phenomenon that complicates differential diagnosis. For example, acute arthritis with features of viral arthritis has been reported after COVID-19, as has crystal-induced arthritis. Arthritides mimicking reactive arthritis (ReA) have also been described, but these patients often do not fulfil the typical features of ReA: several reports describe cases of patients older than 45 years at the onset of arthritis, and the characteristic genetic feature of ReA, HLA-B27, is rarely found. Because viral infections are much less likely to cause ReA than bacterial infections, and respiratory infections are rarely the cause of ReA, it is currently unknown whether SARS-CoV-2 can cause true ReA. Here, we report the case of a 30-year-old patient who presented with acute pain, swelling and redness in the left metatarsophalangeal (MTP) joint and ankle 7 days after resolution of a SARS-CoV-2 infection. Diagnostics revealed arthritis of the MTP2, synovitis of the upper ankle with significant joint effusion and peritendinitis of the flexor tendons. Based on the clinical manifestations and diagnostic test results, ReA appeared to be the most likely cause. A screening for typical ReA-associated infections was negative. The patient was treated with NSAIDs and intra-articular and systemic glucocorticoids. At a follow-up visit after discontinuation of glucocorticoids, the patient was symptom-free. Overall, we observed a ReA with typical clinical, genetic and patient characteristics after SARS-CoV-2 infection, and we conclude that a direct association with COVID-19 is highly plausible.

COVID-19-associated arthritis: an emerging new entity?

The current COVID-19 pandemic raises several clinical challenges. Cases of COVID-19-associated arthritis have been reported, and inconsistently described as either COVID-19 viral arthritis or COVID-19 reactive arthritis. We aimed to review all the reported cases of 'COVID-19-associated arthritis', which we propose, is a better term to define the entire spectrum of new-onset arthritis believed to be associated with SARS-CoV-2 infection. We performed a systematic literature review using MEDLINE, EMBASE and the Cochrane Database of Systematic Reviews to search for articles published up to 13 December 2021. We included cohort studies, case series and case reports describing patients diagnosed with COVID-19 reactive or viral arthritis by a physician, irrespective of fulfilment of classification criteria. To identify relevant studies, medical subject headings and keywords related to 'COVID-19/SARS-CoV-2 infection' and 'reactive arthritis' were used. Our search retrieved 419 articles, of which 31 were included in the review. A total of 33 cases were reported in these 31 articles, the majority being adults (28/33=85%) with peripheral joint involvement (26/33=79%). Most of the patients responded well to treatment and the disease was self-limiting. These 33 case reports describe a possible causal relationship between exposure to SARS-CoV-2 and the onset of arthritis. However, since these cases were reported during a pandemic, other aetiologies cannot be fully excluded. The exact mechanism through which SARS-CoV-2 might trigger arthritis is not fully understood and robust epidemiological data to support a causal relationship are still lacking.

Successful Use of Certolizumab Pegol for Refractory Psoriatic Arthritis Triggered by COVID-19 Infection

Recently, the coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2, has spread worldwide. Although nearly all patients incur mild-to-moderate disease from this viral infection, some develop severe manifestations with a poor prognosis. COVID-19 can also induce autoimmune disease; several cases of arthritis following COVID-19 have been documented in the literature, such as reactive arthritis and chronic arthritis. We herein report a case of psoriatic arthritis triggered by COVID-19. Although the arthritis had been refractory to glucocorticoids and methotrexate, certolizumab pegol subsequently led to remission.

MultiInflammatory Syndrome in Children: A View into Immune Pathogenesis from a Laboratory Perspective

BACKGROUND

Multiinflammatory syndrome in children (MIS-C) is a novel and rare inflammatory disorder associated with severe acute respiratory syndrome coronavirus 2 infection in school-age children. Reports in the past year have suggested a multisystem pathophysiology characterized by hyperinflammation, gastrointestinal distress, and cardiovascular complications. Clinical laboratory investigations, including routine blood testing for inflammatory (e.g., C-reactive protein, ferritin) and cardiac (e.g., troponin, brain natriuretic peptides) markers have provided insight into potential drivers of disease pathogenesis, highlighting the role of the laboratory in the differential diagnosis of patients presenting with similar conditions (e.g., Kawasaki disease, macrophage activating syndrome).

CONTENT

While few studies have applied high-dimensional immune profiling to further characterize underlying MIS-C pathophysiology, much remains unknown regarding predisposing risk factors, etiology, and long-term impact of disease onset. The extent of autoimmune involvement is also unclear. In the current review, we summarize and critically evaluate available literature on potential pathogenic mechanisms underlying MIS-C onset and discuss the current and anticipated value of various laboratory testing paradigms in MIS-C diagnosis and monitoring.

SUMMARY

From initial reports, it is clear that MIS-C has unique inflammatory signatures involving both adaptive and innate systems. Certain cytokines, inflammatory markers, and cardiac markers assist in the differentiation of MIS-C from other hyperinflammatory conditions. However, there are still major gaps in our understanding of MIS-C pathogenesis, including T cell, B cell, and innate response. It is essential that researchers not only continue to decipher initial pathogenesis but also monitor long-term health outcomes, particularly given observed presence of circulating autoantibodies with unknown impact.

SARS-Cov2 acute and post-active infection in the context of autoimmune and chronic inflammatory diseases

The clinical and immunological spectrum of acute and post-active COVID-19 syndrome overlaps with criteria used to characterize autoimmune diseases such as rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). Indeed, following SARS-Cov2 infection, the innate immune response is altered with an initial delayed production of interferon type I (IFN-I), while the NF-kappa B and inflammasome pathways are activated. In lung and digestive tissues, an alternative and extrafollicular immune response against SARS-Cov2 takes place with, consequently, an altered humoral and memory T cell response leading to breakdown of tolerance with the emergence of autoantibodies. However, the risk of developing severe COVID-19 among SLE and RA patients did not exceed the general population except in those having pre-existing neutralizing autoantibodies against IFN-I. Treatment discontinuation rather than COVID-19 infection or vaccination increases the risk of developing flares. Last but not least, a limited number of case reports of individuals having developed SLE or RA following COVID-19 infection/vaccination have been reported. Altogether, the SARS-Cov2 pandemic represents an unique opportunity to investigate the dangerous interplay between the immune response against infectious agents and autoimmunity, and to better understand the triggering role of infection as a risk factor in autoimmune and chronic inflammatory disease development.

New Onset of Autoimmune Diseases Following COVID-19 Diagnosis

There is growing evidence that coronavirus disease 2019 (COVID-19) can lead to a dysregulation of the immune system with the development of autoimmune phenomena. The consequence of this immune dysregulation ranges from the production of autoantibodies to the onset of rheumatic autoimmune disease. In this context, we conducted a systematic review to analyze the current data regarding the new-onset systemic and rheumatic autoimmune diseases in COVID-19 patients. A literature search in PubMed and Scopus databases from December 2019 to September 2021 identified 99 patients that fulfilled the specific diagnostic/classification criteria and/or nomenclature for each rheumatic autoimmune disease. The main diseases reported were vasculitis and arthritis. Idiopathic inflammatory myopathies, systemic lupus erythematosus, and sarcoidosis were also reported in a limited number of patients, as well as isolated cases of systemic sclerosis and adult-onset Still's disease. These findings highlight the potential spectrum of systemic and rheumatic autoimmune diseases that could be precipitated by SARS-CoV-2 infection. Complementary studies are needed to discern the link between the SARS-CoV-2 and new onset-rheumatic diseases so that this knowledge can be used in early diagnosis and the most suitable management.

The intersection of COVID-19 and autoimmunity

Acute COVID-19, caused by SARS-CoV-2, is characterized by diverse clinical presentations, ranging from asymptomatic infection to fatal respiratory failure, and often associated with varied longer-term sequelae. Over the past 18 months, it has become apparent that inappropriate immune responses contribute to the pathogenesis of severe COVID-19. Researchers working at the intersection of COVID-19 and autoimmunity recently gathered at an American Autoimmune Related Diseases Association Noel R. Rose Colloquium to address the current state of knowledge regarding two important questions: Does established autoimmunity predispose to severe COVID-19? And, at the same time, can SARS-CoV-2 infection trigger de novo autoimmunity? Indeed, work to date has demonstrated that 10% to 15% of patients with critical COVID-19 pneumonia exhibit autoantibodies against type I interferons, suggesting that preexisting autoimmunity underlies severe disease in some patients. Other studies have identified functional autoantibodies following infection with SARS-CoV-2, such as those that promote thrombosis or antagonize cytokine signaling. These autoantibodies may arise from a predominantly extrafollicular B cell response that is more prone to generating autoantibody-secreting B cells. This Review highlights the current understanding, evolving concepts, and unanswered questions provided by this unique opportunity to determine mechanisms by which a viral infection can be exacerbated by, and even trigger, autoimmunity. The potential role of autoimmunity in post-acute sequelae of COVID-19 is also discussed.

Bilateral shoulder arthritis in COVID-19 patient after prolonged mechanical ventilation assist: a case report

Prolonged immobilization and, in particular, mechanical ventilation, have been linked to muscle atrophy. Anecdotal reports in the literature describe rhabdomyolysis as a potential late complication of COVID-19 infection which, in severe cases, may coexist with fluid collections. We report a case of a 28-year-old patient that had been recently hospitalized with SARS-CoV-2 pneumonia, with need for invasive ventilation support. Days after being discharged, the patient presents with retrosternal thoracalgia irradiating to the left upper limb. On physical examination, abduction and external rotation were limited due to pain complaints and there was soft tissue swelling of the corresponding shoulder and arm. Imaging evaluation was essential to establish the underlying condition, revealing bilateral arthritis communicating with large rotator cuff collections, which was considered of septic nature.

Post-COVID-19 Arthritis and Sacroiliitis: Natural History with Longitudinal Magnetic Resonance Imaging Study in Two Cases and Review of the Literature

Severe acute respiratory coronavirus-2 syndrome (SARS-CoV-2) is a well-known pandemic infectious disease caused by an RNA virus belonging to the coronaviridae family. The most important involvement during the acute phase of infection concerns the respiratory tract and may be fatal. However, COVID-19 may become a systemic disease with a wide spectrum of manifestations. Herein, we report the natural history of sacroiliac inflammatory involvement in two females who developed COVID-19 infection with mild flu-like symptoms. After the infection they reported inflammatory back pain, with magnetic resonance imaging (MRI) studies showing typical aspects of sacroiliitis. Symptoms improved with NSAIDs therapy over the following months while MRI remained positive. A literature review was performed on this emerging topic. To our knowledge, this is the first MRI longitudinal study of post-COVID-19 sacroiliitis with almost one year of follow-up. Predisposing factors for the development of articular involvement are unclear but a long-lasting persistence of the virus, demonstrated by nasopharyngeal swab, may enhance the probability of altering the immune system in a favourable background.

A case of SARS-CoV-2-associated arthritis with detection of viral RNA in synovial fluid

Severe acute respiratory distress syndrome-coronavirus-2 (SARS-CoV-2) provokes symptoms ranging from mild viral illness to a systemic inflammatory syndrome with multi-organ failure and has been associated with cases of arthritis. We report a clinical case of SARS-CoV-2 associated arthritis in which analysis of synovial fluid detected SARS-CoV-2 ribonucleic acid.

[Post-Corona-Virus-Disease‑19 arthritis. Manifestation under the clinical picture of a reactive arthritis]

A total of 13 case reports of reactive arthritis reported in the literature in connection with coronavirus disease 2019 (COVID‑19) are reviewed. Men were affected more frequently than women. The arthritis was manifested 4-44 days after the infection or the occurrence of the COVID‑19 symptoms. Acute arthritis was monoarticular or oligoarticular. Only 1 out of 7 patients examined was human-leucocyte-antigen(HLA)-B27 positive. A direct viral infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) could not be detected in the synovial fluid and was not investigated in the synovial membrane. The arthritis was successfully treated with nonsteroidal anti-inflammatory drugs and/or intra-articular or systemic corticosteroids. The pathogenesis of post-COVID‑19 reactive arthritis is unknown.

COVID-19 and RA share an SPP1 myeloid pathway that drives PD-L1+ neutrophils and CD14+ monocytes

We explored the potential link between chronic inflammatory arthritis and COVID-19 pathogenic and resolving macrophage pathways and their role in COVID-19 pathogenesis. We found that bronchoalveolar lavage fluid (BALF) macrophage clusters FCN1+ and FCN1+SPP1+ predominant in severe COVID-19 were transcriptionally related to synovial tissue macrophage (STM) clusters CD48hiS100A12+ and CD48+SPP1+ that drive rheumatoid arthritis (RA) synovitis. BALF macrophage cluster FABP4+ predominant in healthy lung was transcriptionally related to STM cluster TREM2+ that governs resolution of synovitis in RA remission. Plasma concentrations of SPP1 and S100A12 (key products of macrophage clusters shared with active RA) were high in severe COVID-19 and predicted the need for Intensive Care Unit transfer, and they remained high in the post-COVID-19 stage. High plasma levels of SPP1 were unique to severe COVID-19 when compared with other causes of severe pneumonia, and IHC localized SPP1+ macrophages in the alveoli of COVID-19 lung. Investigation into SPP1 mechanisms of action revealed that it drives proinflammatory activation of CD14+ monocytes and development of PD-L1+ neutrophils, both hallmarks of severe COVID-19. In summary, COVID-19 pneumonitis appears driven by similar pathogenic myeloid cell pathways as those in RA, and their mediators such as SPP1 might be an upstream activator of the aberrant innate response in severe COVID-19 and predictive of disease trajectory including post-COVID-19 pathology.

Axial and peripheral spondyloarthritis triggered by sars-cov-2 infection: a report of two cases

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can show musculoskeletal symptoms such as peripheral arthritis. In rare cases, peripheral arthritis can develop after the resolution of SARS-CoV-2. We present two cases of spondyloarthritis induced by SARS-CoV-2; one case with axial and peripheral spondyloarthritis and the other with peripheral spondyloarthritis. Both cases refer to Lebanese patients who were HLA-B27 positive. These two cases highlight the possible predisposition of HLA-B27 positive patients to the development of spondyloarthritis symptoms triggered by SARS-CoV-2.

Autoimmune and Rheumatic Manifestations Associated With COVID-19 in Adults: An Updated Systematic Review

Background: Numerous cases of the coronavirus disease 2019 (COVID-19) with autoimmune and rheumatic manifestations have been reported. Despite the available reviews that summarized its autoimmune/rheumatic manifestations, a systematic approach is still lacking. Therefore, we conducted a comprehensive systematic review in order to give an overview upon these rare but clinically significant manifestations.

Methods: We performed a literature search of PubMed and EMBASE as of October 9, 2020. All articles relevant to either systemic or organ-specific autoimmune and rheumatic manifestations potentially associated with COVID-19 were collected. The reviewed literature were limited to adults ≥18 years.

Results: Although most of the existing evidence was based on case reports or case series without a long-term follow-up, a variety of autoimmune/rheumatic manifestations were associated with COVID-19. The manifestations that have a consistent association with COVID-19 include autoimmune cytopenia, cutaneous vasculitis, encephalitis, and Guillain-Barre syndrome. Such association is conflicting as regards to antiphospholipid syndrome, hemophagocytic lymphohistiocytosis, and myasthenia gravis.

Conclusion: Our systematic review indicated the potential of the COVID-19 virus to trigger a myriad of autoimmune and rheumatic manifestations, which should be considered amid global efforts to combat COVID-19.

The JANUS of chronic inflammatory and autoimmune diseases onset during COVID-19 - A systematic review of the literature

The diverse clinical manifestations of COVID-19 is emerging as a hallmark of the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) infection. While the initial target of SARS-CoV-2 is the respiratory tract, it is becoming increasingly clear that there is a complex interaction between the virus and the immune system ranging from mild to controlling responses to exuberant and dysfunctional multi-tissue directed autoimmune responses. The immune system plays a dual role in COVID-19, being implicated in both the anti-viral response and in the acute progression of the disease, with a dysregulated response represented by the marked cytokine release syndrome, macrophage activation, and systemic hyperinflammation. It has been speculated that these immunological changes may induce the loss of tolerance and/or trigger chronic inflammation. In particular, molecular mimicry, bystander activation and epitope spreading are well-established proposed mechanisms to explain this correlation with the likely contribution of HLA alleles. We performed a systematic literature review to evaluate the COVID-19-related autoimmune/rheumatic disorders reported between January and September 2020. In particular, we investigated the cases of incident hematological autoimmune manifestations, connective tissue diseases, antiphospholipid syndrome/antibodies, vasculitis, Kawasaki-like syndromes, acute arthritis, autoimmune-like skin lesions, and neurologic autoimmune conditions such as Guillain–Barré syndrome. We screened 6263 articles and report herein the findings of 382 select reports which allow us to conclude that there are 2 faces of the immune response against SARS-CoV-2, that include a benign virus controlling immune response and a many faceted range of dysregulated multi-tissue and organ directed autoimmune responses that provides a major challenge in the management of this viral disease. The number of cases for each disease varied significantly while there were no reported cases of adult onset Still disease, systemic sclerosis, or inflammatory myositis.

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The immune system plays a major role in the acute progression of COVID-19.

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SARS-CoV-2 infection shares features with autoimmune diseases.

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SARS-CoV-2 can induce Guillain-Barré syndrome, arthritis, chilblain-like lesions.

Sarilumab use in severe SARS-CoV-2 pneumonia

BACKGROUND

Interleukin-6 signal blockade showed preliminary beneficial effects in treating inflammatory response against SARS-CoV-2 leading to severe respiratory distress. Herein we describe the outcomes of off-label intravenous use of Sarilumab in severe SARS-CoV-2-related pneumonia.

METHODS

53 patients with SARS-CoV-2 severe pneumonia received intravenous Sarilumab; pulmonary function improvement or Intensive Care Unit (ICU) admission rate in medical wards, live discharge rate in ICU treated patients and safety profile were recorded. Sarilumab 400 mg was administered intravenously on day 1, with eventual additional infusion based on clinical judgement, and patients were followed for at least 14 days, unless previously discharged or dead.

FINDINGS

Of the 53 SARS-CoV-2pos patients receiving Sarilumab, 39(73·6%) were treated in medical wards [66·7% with a single infusion; median PaO2/FiO2:146(IQR:120-212)] while 14(26·4%) in ICU [92·6% with a second infusion; median PaO2/FiO2: 112(IQR:100-141.5)].Within the medical wards, 7(17·9%) required ICU admission, 4 of whom were re-admitted to the ward within 5-8 days. At 19 days median follow-up, 89·7% of medical inpatients significantly improved (46·1% after 24 h, 61·5% after 3 days), 70·6% were discharged from the hospital and 85·7% no longer needed oxygen therapy. Within patients receiving Sarilumab in ICU, 64·2% were discharged from ICU to the ward and 35·8% were still alive at the last follow-up. Overall mortality rate was 5·7%.

INTERPRETATION

IL-6R inhibition appears to be a potential treatment strategy for severe SARS-CoV-2 pneumonia and intravenous Sarilumab seems a promising treatment approach showing, in the short term, an important clinical outcome and good safety.