Polymyalgia rheumatica and giant cell arteritis following COVID-19 vaccination: Results from a nationwide survey

We conducted a national in-depth analysis including pharmacovigilance reports and clinical study to assess the reporting rate (RR) and to determine the clinical profile of polymyalgia rheumatica (PMR) and giant cell arteritis (GCA) in COVID-19-vaccinated individuals. First, based on the French pharmacovigilance database, we estimated the RR of PMR and GCA cases in individuals aged over 50 who developed their initial symptoms within one month of receiving the BNT162b2 mRNA, mRNA-1273, ChAdOx1 nCoV-19, and Ad26.COV2.S vaccines. We then conducted a nationwide survey to gather clinical profiles, therapeutic management, and follow-up data from individuals registered in the pharmacovigilance study. A total of 70 854 684 COVID-19 vaccine doses were administered to 25 260 485 adults, among which, 179 cases of PMR (RR 7. 1 cases/1 000 000 persons) and 54 cases of GCA (RR 2. 1 cases/1 000 000 persons) have been reported. The nationwide survey allowed the characterization of 60 PMR and 35 GCA cases. Median time to the onset of first symptoms was 10 (range 2-30) and 7 (range 2-25) days for PMR and GCA, respectively. Phenotype, GCA-related ischemic complications and -large vessel vasculitis as well as therapeutic management and follow-up seemed similar according to the number of vaccine shots received and when compared to the literature data of unvaccinated population. Although rare, the short time between immunization and the onset of first symptoms of PMR and GCA suggests a temporal association. Physician should be aware of this potential vaccine-related phenomenon.

Mortality, cardiac and cerebral damages reduction by IL-1 inhibition in a murine model of TTP

Thrombotic thrombocytopenic purpura (TTP), a rare but fatal disease if untreated, is due to alteration in Von Willebrand factor cleavage resulting in capillary microthrombi formation and ischemic organ damage. Interleukin-1 (IL-1), has been shown to drive sterile inflammation following ischemia and could play an essential contribution to post-ischemic organ damage in TTP. Our objectives were to evaluate IL-1 involvement during TTP and to test the efficacy of the recombinant IL-1 receptor antagonist, anakinra, in a murine TTP model. We retrospectively measured plasmatic IL-1 concentrations in TTP patients and controls. TTP patients exhibited elevated plasma IL-1α and β concentrations, which correlated with disease course and survival. In a TTP mouse model, we administered anakinra (IL-1 inhibitor) or placebo for 5 days and evaluated the efficacy of this treatment. Anakinra significantly reduced mortality of mice (P<0.001). Anakinra significantly decreased TTP-induced cardiac damages as assessed by blood troponin concentrations, evaluation of left ventricular function by echocardiography, [18F]FDG PET of myocardial glucose metabolism, and cardiac histology. Anakinra also significantly reduced brain TTP-induced damages, evaluated through blood PS100b concentrations, nuclear imaging and histology. We finally showed that IL-1α and β trigger endothelial degranulation in vitro, leading to the release of Von Willebrand factor. In conclusion, Anakinra significantly reduced TTP mortality in a pre-clinical model of the disease by inhibiting both endothelial degranulation and post-ischemic inflammation, supporting further evaluations in humans.

Diagnosis of thrombotic thrombocytopenic purpura: Easy-to-use fiber-optic surface plasmon resonance immunoassays for automated ADAMTS13 antigen and conformation evaluation

BACKGROUND

Laboratory diagnosis of immune-mediated thrombotic thrombocytopenic purpura (iTTP) remains challenging when ADAMTS13 activity ranges between 10-20%. To prevent misdiagnosis, open ADAMTS13 conformation gained clinical attention as a novel biomarker especially to diagnose acute iTTP in patient with diagnostic undecisive ADAMTS13 activity. Plasma ADAMTS13 conformation analysis corrects for ADAMTS13 antigen with both parameters being characterized in enzyme-linked immunosorbent assay (ELISA)-based reference assays requiring expert technicians.

OBJECTIVES

To design ADAMTS13 antigen and conformation assays on automated, easy-to-use fiber-optic surface plasmon resonance (FO-SPR) technology to promote assay accessibility and diagnose challenging iTTP patients.

PATIENTS/METHODS

ADAMTS13 antigen and conformation assays were designed on FO-SPR technology. Plasma of twenty healthy donors and twenty acute iTTP patients were quantified and data from FO-SPR and ELISA reference assays were compared.

RESULTS

Following assay design, both antigen and conformation FO-SPR assays were optimized and characterized presenting strong analytical sensitivity (detection limit of 0.001 μg/mL) and repeatability (inter-assay variation of 14.4%). Comparative analysis suggests positive correlation (Spearman r of 0.92) and good agreement between FO-SPR and ELISA assays. As expected, FO-SPR assays showed a closed or open ADAMTS13 conformation in healthy donors and acute iTTP patients respectively.

CONCLUSIONS

Both ADAMTS13 antigen and conformation assays were transferred onto automated, easy-to-use FO-SPR technology displaying potent analytical sensitivity and reproducibility. ADAMTS13 antigen and conformation were determined for healthy donors and acute iTTP patients showing strong correlation with ELISA reference. Introducing FO-SPR technology in clinical context could support routine diagnosis of acute iTTP patients, notably when ADAMTS13 activity fluctuates between 10-20%.

[High anti-topoisomerase-1 autoantibodies levels are associated with the extension of skin fibrosis and vascular progression in patients with systemic sclerosis]

BACKGROUND

Anti-centromere antibodies, anti-topoisomerase-1 antibodies (ATA), and anti-RNA-polymerase III antibodies are three Systemic Sclerosis (SSc)-specific autoantibodies. Their detection is helpful in determining the prognosis. We aimed to evaluate whether ATA levels were associated with disease severity at diagnosis or disease progression during follow-up in ATA positive patients.

METHODS

We conducted a single-centre French retrospective observational study, between 2014 and 2021. ATA positive patients fulfilling the ACR/EULAR 2013 classification criteria for SSc with a minimal follow-up of 1 year and 2 ATA dosages were included. SSc patients with high IgG ATA levels at baseline (>240IU/mL) were compared with SSc patients with low levels (≤240IU/mL), at inclusion and at 1 and 3 years. A variation of at least 30 % of ATA levels was considered significant.

RESULTS

Fifty-nine SSc patients were included and analysed. There was a predominance of women and of patients with diffuse interstitial lung disease. Patients with high ATA levels exhibited a higher skin sclerosis assessed by the modified Rodnan skin score (P=0.0480). They had a lower carbon monoxide transfer coefficient (P=0.0457), a lower forced vital capacity (FVC) (P=0.0427) and more frequently had a FVC under 80 %, when compared to patients with low ATA levels (P=0.0423). Initial high ATA levels were associated with vascular progression at one year (21.95 % vs. 0 %; P=0.0495).

CONCLUSION

ATA levels are associated with skin sclerosis and vascular progression in SSc. Beyond the detection of ATA, quantifying this autoantibody might be of interest in predicting disease severity and prognosis in SSc.

Molecular B-cell clonality assay in minor salivary glands as a useful tool for the lymphoma risk assessment in Sjögren's syndrome

OBJECTIVES

Non-Hodgkin's lymphoma (NHL) risk assessment is crucial in Sjögren's syndrome (SS). We studied the prevalence of clonal immunoglobulin gene rearrangements in minor salivary glands (MSG) and their correlations with lymphoma occurrence and with previously established NHL predictors.

METHODS

Molecular B-cell expansion was studied in fresh-frozen MSG of 207 patients with either suspected SS or with suspected lymphoma during SS, using a standardised multiplex PCR assay combined with heteroduplex analysis by microcapillary electrophoresis. The assignation of clonal cases was based on EuroClonality consortium guidelines.

RESULTS

Among 207 studied patients, 31 (15%) had MSG monoclonal B-cell infiltration. Monoclonality was significantly more frequent in patients with SS (28/123, 22.8%) compared with patients without SS (3/84, 3.6%, P<0.001). Monoclonal B-cell infiltration in MSG of SS patients correlated significantly with ongoing salivary gland NHL, salivary gland swelling, CD4+ T-cell lymphopenia, rheumatoid factor (RF) activity, low complement levels and type 2 mixed cryoglobulinemia. The accumulation of biological risk factors was associated with a higher rate of MSG B-cell monoclonality given that patients with only positive RF had no probability of MSG B-cell monoclonality, RF-positive patients with 1 or 2 other risk factors had a 25.0% and 85.7% probability of MSG B-cell monoclonality, respectively.

CONCLUSION

The detection of MSG monoclonal B-cell expansion by this easy-to-perform molecular assay is useful, both at the time of diagnosis and during the course of SS. Monoclonal B-cell expansion is associated with a subset of SS patients presenting either ongoing lymphoma or other established lymphoma predictive factors.

Macrophage IL-1β-positive microvesicles exhibit thrombo-inflammatory properties and are detectable in patients with active juvenile idiopathic arthritis

Objective

IL-1β is a leaderless cytokine with poorly known secretory mechanisms that is barely detectable in serum of patients, including those with an IL-1β-mediated disease such as systemic juvenile idiopathic arthritis (sJIA). Leukocyte microvesicles (MVs) may be a mechanism of IL-1β secretion. The first objective of our study was to characterize IL-1β-positive MVs obtained from macrophage cell culture supernatants and to investigate their biological functions in vitro and in vivo. The second objective was to detect circulating IL-1β-positive MVs in JIA patients.

Methods

MVs were purified by serial centrifugations from PBMCs, or THP-1 differentiated into macrophages, then stimulated with LPS ± ATP. MV content was analyzed for the presence of IL-1β, NLRP3 inflammasome, caspase-1, P2X7 receptor, and tissue factor (TF) using ELISA, Western blot, or flow cytometry. MV biological properties were studied in vitro by measuring VCAM-1, ICAM-1, and E-selectin expression after HUVEC co-culture and factor-Xa generation test was realized. In vivo, MVs' ability to recruit leukocytes in a murine model of peritonitis was evaluated. Plasmatic IL-1β-positive MVs were studied ex vivo in 10 active JIA patients using flow cytometry.

Results

THP-1-derived macrophages stimulated with LPS and ATP released MVs, which contained NLRP3, caspase-1, and the 33-kDa precursor and 17-kDa mature forms of IL-1β and bioactive TF. IL-1β-positive MVs expressed P2X7 receptor and released soluble IL-1β in response to ATP stimulation in vitro. In mice, MVs induced a leukocyte peritoneal infiltrate, which was reduced by treatment with the IL-1 receptor antagonist. Finally, IL-1β-positive MVs were detectable in plasma from 10 active JIA patients.

Conclusion

MVs shed from activated macrophages contain IL-1β, NLRP3 inflammasome components, and TF, and constitute thrombo-inflammatory vectors that can be detected in the plasma from active JIA patients.

NLRP3 inflammasome and interleukin-1 contributions to COVID-19-associated coagulopathy and immunothrombosis

Immunothrombosis-immune-mediated activation of coagulation-is protective against pathogens, but excessive immunothrombosis can result in pathological thrombosis and multiorgan damage, as in severe coronavirus disease 2019 (COVID-19). The NACHT-, LRR-, and pyrin domain-containing protein 3 (NLRP3) inflammasome produces major proinflammatory cytokines of the interleukin (IL)-1 family, IL-1β and IL-18, and induces pyroptotic cell death. Activation of the NLRP3 inflammasome pathway also promotes immunothrombotic programs including release of neutrophil extracellular traps and tissue factor by leukocytes, and prothrombotic responses by platelets and the vascular endothelium. NLRP3 inflammasome activation occurs in patients with COVID-19 pneumonia. In preclinical models, NLRP3 inflammasome pathway blockade restrains COVID-19-like hyperinflammation and pathology. Anakinra, recombinant human IL-1 receptor antagonist, showed safety and efficacy and is approved for the treatment of hypoxaemic COVID-19 patients with early signs of hyperinflammation. The non-selective NLRP3 inhibitor colchicine reduced hospitalization and death in a subgroup of COVID-19 outpatients but is not approved for the treatment of COVID-19. Additional COVID-19 trials testing NLRP3 inflammasome pathway blockers are inconclusive or ongoing. We herein outline the contribution of immunothrombosis to COVID-19-associated coagulopathy, and review preclinical and clinical evidence suggesting an engagement of the NLRP3 inflammasome pathway in the immunothrombotic pathogenesis of COVID-19. We also summarize current efforts to target the NLRP3 inflammasome pathway in COVID-19, and discuss challenges, unmet gaps, and the therapeutic potential that inflammasome-targeted strategies may provide for inflammation-driven thrombotic disorders including COVID-19.

Measuring ADAMTS-13 activity to diagnose thrombotic thrombocytopenic purpura: a novel, fast fiber-optic surface plasmon resonance immunoassay

Background

Thrombotic thrombocytopenic purpura (TTP) is characterized by severe ADAMTS-13 activity deficiency (<10%). Diagnostic testing is challenging because of unavailability, high cost, and expert technician requirement of ADAMTS-13 enzyme assays. Cost-effective, automated fiber-optic surface plasmon resonance (FO-SPR) platforms show potential for developing diagnostic tests. Yet, FO-SPR has never been explored to measure enzymatic activities.

Objectives

To develop an easy-to-use ADAMTS-13 activity assay utilizing optical fibers to rapidly diagnose TTP.

Methods

The ADAMTS-13 activity assay was designed and optimized using FO-SPR technology based on a previously described enzyme-linked immunosorbent assay setup. A calibration curve was generated to quantify ADAMTS-13 activity in plasma of healthy donors and patients with acute immune-mediated TTP (iTTP), hemolytic uremic syndrome, or sepsis. ADAMTS-13 activity data from FO-SPR and fluorescence resonance energy transfer-based strategies (FRETS)-VWF73 reference assays were compared.

Results

After initial assay development, optimization improved read-out magnitude and signal-to-noise ratio and reduced variation. Further characterization demonstrated a detection limit (6.8%) and inter-assay variation (Coefficient of variation, 7.2%) that showed good analytical sensitivity and repeatability. From diverse plasma samples, only plasma from patients with acute iTTP showed ADAMTS-13 activities below 10%. Strong Pearson correlation (r = 0.854) between FO-SPR and reference FRETS-VWF73 assays were observed for all measured samples.

Conclusions

A fast ADAMTS-13 activity assay was designed onto automated FO-SPR technology. Optimization resulted in sensitive ADAMTS-13 activity measurements with a detection limit enabling clinical diagnosis of TTP within 3 hours. The FO-SPR assay proved strong correlation with the reference FRETS-VWF73 assay. For the first time, this assay demonstrated the capacity of FO-SPR technology to measure enzymatic activity in pre-clinical context.

Anti-Jo-1 autoantibodies: biomarkers of severity and evolution of the disease in antisynthetase syndrome

BACKGROUND

Anti-Jo-1 autoantibodies represent essential markers in the diagnosis of antisynthetase syndrome (ASS). In this retrospective study, we aimed to investigate whether their concentrations and fluctuations could both respectively reflect the severity and evolution of ASS.

METHODS

Between 2015 and 2020, clinical and biological features of ASS patients with at least one positive measure of anti-Jo-1 autoantibody were collected. At each serum sampling, we assessed myositis activity by using the Myositis Intention to Treat Activities Index (MITAX) and compared anti-Jo-1 concentrations with ASS severity, anti-Jo-1 concentrations between patients with and without active disease, and changes in anti-Jo-1 concentrations with disease activity.

RESULTS

Forty-eight patients with ASS had at least one positive determination of anti-Jo-1 concentration. Among them, twenty-nine patients had at least two determinations of anti-Jo-1 autoantibody in their follow-up. We showed that these autoantibody concentrations were significantly correlated with MITAX (r = 0.4, p = 0.03) and creatine kinase concentration (r = 0.34, p = 0.002) and that they were significantly higher in patients with active disease than in those with inactive disease (91.7 IU/L vs 44.4 IU/L, p = 0.016). During follow-up, we found a significant correlation between fluctuations of anti-Jo-1 autoantibody concentrations and MITAX score (r = 0.7, p < 0.0001).

CONCLUSION

Our results suggest that anti-Jo-1 autoantibody concentration could be a predictive marker of the severity and evolution of ASS and show that their quantification could represent a precious tool for disease monitoring and for improving the therapeutic management of ASS patients.

Predictors of Relapses or Recurrences in Patients With Giant Cell Arteritis: A Medical Records Review Study

OBJECTIVE

Giant cell arteritis (GCA) is the most common systemic vasculitis in individuals aged ≥50 years. Its course is marked by a high relapse rate requiring long-term glucocorticoid use with its inherent adverse effects. We aimed to identify factors associated with relapses or recurrences in GCA at diagnosis.

METHODS

We reviewed the medical records of consecutive patients with GCA diagnosed between 2009 and 2019 and followed for at least 12 months. We recorded their characteristics at onset and during follow-up. Factors associated with relapses or recurrences were identified using multivariable analysis.

RESULTS

We included 153 patients, among whom 68% were female with a median age of 73 (47-98) years and a median follow-up of 32 (12-142) months. Seventy-four patients (48.4%) had at least 1 relapse or recurrence. Headache and polymyalgia rheumatica were the most frequent manifestations of relapses. The first relapse occurred at a median time of 13 months after the diagnosis, with a median dose of 5.5 (0-25) mg/d of glucocorticoids.In multivariable analysis, patients with relapses or recurrences had a higher frequency of cough and scalp tenderness at diagnosis (20.3% vs 5.1%; odds ratio [OR], 4.73; 95% confidence interval [CI], 1.25-17.94; p = 0.022; and 41.9% vs 29.1%; OR, 2.4; 95% CI, 1.07-5.39; p = 0.034, respectively). Patients with diabetes mellitus at diagnosis had fewer relapses or recurrences during follow-up (5.4% vs 19%; OR, 0.24; 95% CI, 0.07-0.83; p = 0.024).

CONCLUSIONS

Cough and scalp tenderness at diagnosis were associated with relapses or recurrences, whereas patients with diabetes experienced fewer relapses or recurrences.

Tocilizumab versus anakinra in COVID-19: results from propensity score matching

Background

Tocilizumab and anakinra are anti-interleukin drugs to treat severe coronavirus disease 2019 (COVID-19) refractory to corticosteroids. However, no studies compared the efficacy of tocilizumab versus anakinra to guide the choice of the therapy in clinical practice. We aimed to compare the outcomes of COVID-19 patients treated with tocilizumab or anakinra.

Methods

Our retrospective study was conducted in three French university hospitals between February 2021 and February 2022 and included all the consecutive hospitalized patients with a laboratory-confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection assessed by RT-PCR who were treated with tocilizumab or anakinra. A propensity score matching was performed to minimize confounding effects due to the non-random allocation.

Results

Among 235 patients (mean age, 72 years; 60.9% of male patients), the 28-day mortality (29.4% vs. 31.2%, p = 0.76), the in-hospital mortality (31.7% vs. 33.0%, p = 0.83), the high-flow oxygen requirement (17.5% vs. 18.3%, p = 0.86), the intensive care unit admission rate (30.8% vs. 22.2%, p = 0.30), and the mechanical ventilation rate (15.4% vs. 11.1%, p = 0.50) were similar in patients receiving tocilizumab and those receiving anakinra. After propensity score matching, the 28-day mortality (29.1% vs. 30.4%, p = 1) and the rate of high-flow oxygen requirement (10.1% vs. 21.5%, p = 0.081) did not differ between patients receiving tocilizumab or anakinra. Secondary infection rates were similar between the tocilizumab and anakinra groups (6.3% vs. 9.2%, p = 0.44).

Conclusion

Our study showed comparable efficacy and safety profiles of tocilizumab and anakinra to treat severe COVID-19.

French recommendations for the management of non-infectious chronic uveitis

This French National Diagnostic and Care Protocol (NDPC) includes both pediatric and adult patients with non-infectious chronic uveitis (NICU) or non-infectious recurrent uveitis (NIRU). NICU is defined as uveitis that persists for at least 3 months or with frequent relapses occurring less than 3 months after cessation of treatment. NIRU is repeated episodes of uveitis separated by periods of inactivity of at least 3 months in the absence of treatment. Some of these NICU and NIRU are isolated. Others are associated with diseases that may affect various organs, such as uveitis associated with certain types of juvenile idiopathic arthritis, adult spondyloarthropathies or systemic diseases in children and adults such as Behçet's disease, granulomatoses or multiple sclerosis. The differential diagnoses of pseudo-uveitis, sometimes related to neoplasia, and uveitis of infectious origin are discussed, as well as the different forms of uveitis according to their main anatomical location (anterior, intermediate, posterior or panuveitis). We also describe the symptoms, known physiopathological mechanisms, useful complementary ophthalmological and extra-ophthalmological examinations, therapeutic management, monitoring and useful information on the risks associated with the disease or treatment. Finally, this protocol presents more general information on the care pathway, the professionals involved, patient associations, adaptations in the school or professional environment and other measures that may be implemented to manage the repercussions of these chronic diseases. Because local or systemic corticosteroids are usually necessary, these treatments and the risks associated with their prolonged use are the subject of particular attention and specific recommendations. The same information is provided for systemic immunomodulatory treatments, immunosuppressive drugs, sometimes including anti-TNFα antibodies or other biotherapies. Certain particularly important recommendations for patient management are highlighted in summary tables.

Characteristics of ANCA-associated vasculitis with aneurysms: Case series and review of the literature

INTRODUCTION

ANCA-associated vasculitis (AAV) is an exceptional cause of small and large vascular aneurysms. Here, we present the phenotypic characteristics of patients with AAV associated with the presence of aneurysms.

METHODS

We conducted a retrospective multicenter study and a systematic review of the literature. Only AAV patients with positive ANCA results and > 1 aneurysm(s) were enrolled. Patients were recruited through a call of observations among the French Vasculitis Study Group (FVSG) and the French Internal Medicine Network. Patients with aneurysm rupture were compared to those without.

RESULTS

We enrolled 51 patients in the cohort, including 31 (67%) with granulomatosis with polyangiitis. The median Birmingham Vasculitis Activity Score was 18 [6-41]. A total of 92 aneurysms were noted, 74% of which involved medium-sized arteries, particularly the renal artery. During a follow-up of 24 [6-56] months, 22 (43%) patients experienced aneurysmal rupture, 91% of which involved medium-sized vessels. Patients with aneurysmal rupture showed significantly more pulmonary infiltrates and higher creatinine levels at baseline than patients without rupture. Initial treatments did not differ between the two groups. Ten (20%) patients died during the follow-up, including three from an aneurysmal rupture.

CONCLUSION

Aneurysms were more frequently observed in GPA patients and predominantly affected medium-sized vessels, especially the renal arteries. The risk of rupture was high and occurred in >40% of patients. Because of their increased mortality, further studies are required to better manage this subset of patients.

Hospitalisation pour infection chez les patients suivis pour une artérite à cellules géantes : étude monocentrique rétrospective

INTRODUCTION

Infections are associated with morbimortality of patients with giant cell arteritis (GCA). The aim of this work was twofold: the identification of factors predisposing to the risk of infection and the description of patients hospitalized with an infection occurring during the treatment period of CAG.

METHODS

A monocentric retrospective study was conducted in GCA patients, comparing patients hospitalized for infection with patients without infection. The analysis included 21/144 (14.6%) patients with 26 infections (cases) and 42 control matched on sex, age, and diagnosis of GCA.

RESULTS

Both groups were similar except for a higher frequency of seritis in cases (15% vs. 0%, p=0.03). Relapses of GCA were less common in cases (23.8% vs 50.0%, p=0.041). Hypogammaglobulinemia was present during infection. More than half of the infections (53.8%) occurred in the first year of follow-up with an average dose of 15mg/day of corticosteroids. Infections were mainly pulmonary (46.2%) and cutaneous (26.9%).

CONCLUSION

Factors associated with infectious risk were identified. This preliminary monocentric work will continue with a national multicentre study.

BIOMARKERS: CAN THEY REALLY GUIDE OUR DAILY PRACTICE?

ABSTRACT

Optimal management of septic patients requires accurate assessment of both current severity status and prognosis. Since the 1990s, substantial advances have been made in the use of circulating biomarkers for such assessments. This summary of the session on "Biomarkers: can they really use guide our daily practice?" presented at the 2021 WEB-CONFERENCE OF THE EUROPEAN SHOCK SOCIETY, 6 November 2021. These biomarkers include ultrasensitive detection of bacteremia, circulating soluble urokina-type plasminogen activator receptor (suPAR), C-reactive protein (CRP) and ferritin and procalcitonin. In addition, the potential application of novel multiwavelength optical biosensor technology allows noninvasive monitoring of multiple metabolites that can be used to assess severity and prognosis in septic patients. The application these biomarkers and improved technologies provide the potential for improved personalized management of septic patients.

Is Endothelial Activation a Critical Event in Thrombotic Thrombocytopenic Purpura?

Thrombotic thrombocytopenic purpura (TTP) is a severe thrombotic microangiopathy. The current pathophysiologic paradigm suggests that the ADAMTS13 deficiency leads to Ultra Large-Von Willebrand Factor multimers accumulation with generation of disseminated microthrombi. Nevertheless, the role of endothelial cells in this pathology remains an issue. In this review, we discuss the various clinical, in vitro and in vivo experimental data that support the important role of the endothelium in this pathology, suggesting that ADAMTS13 deficiency may be a necessary but not sufficient condition to induce TTP. The "second hit" model suggests that in TTP, in addition to ADAMTS13 deficiency, endogenous or exogenous factors induce endothelial activation affecting mainly microvascular cells. This leads to Weibel-Palade bodies degranulation, resulting in UL-VWF accumulation in microcirculation. This endothelial activation seems to be worsened by various amplification loops, such as the complement system, nucleosomes and free heme.

Immune thrombotic thrombocytopenic purpura plasmas induce calcium- and IgG-dependent endothelial activation: correlations with disease severity

Immune-mediated thrombotic thrombocytopenic purpura (iTTP) is characterized by a severe ADAMTS13 deficiency due to the presence of anti-ADAMTS13 autoantibodies, with subsequent accumulation of circulating ultra-large von Willebrand Factor (VWF) multimers. The role of endothelial cell activation as a trigger of the disease has been suggested in animal models but remains to be demonstrated in humans. We prospectively obtained plasma from the first plasma exchange of 25 patients during iTTP acute phase. iTTP but not control plasma, induced a rapid VWF release and P-selectin exposure on dermal human micro-vascular endothelial cell (HMVEC-d) surface, associated with angiopoietin-2 and endothelin-1 secretion, consistent with Weibel-Palade bodies exocytosis. Calcium (Ca2+) blockade significantly decreased VWF release, whereas iTTP plasma induced a rapid and sustained Ca2+ flux in HMVEC-d which correlated in retrospect, with disease severity and survival in 62 iTTP patients. F(ab)’2 fragments purified from the immunoglobulin G (IgG) fraction of iTTP plasma mainly induced endothelial cell (EC) activation with additional minor roles for circulating free heme and nucleosomes, but not for complement. Furthermore, two anti-ADAMTS13 monoclonal antibodies purified from iTTP patient B cells, but not serum from hereditary TTP, induced endothelial Ca2+ flux associated with Weibel-Palade bodies exocytosis in vitro, whereas inhibition of endothelial ADAMTS13 expression using small interference RNA, significantly decreased the stimulating effects of iTTP IgG. In conclusion, Ca2+-mediated endothelial cell activation constitutes a second “hit” of iTTP, is correlated with the severity of the disease and may constitute a possible therapeutic target.

Immune‐mediated thrombotic thrombocytopenic purpura prognosis is affected by blood pressure

Background

The prevalence, prognostic role, and diagnostic value of blood pressure in immune-mediated thrombotic thrombocytopenic purpura (iTTP) and other thrombotic microangiopathies (TMAs) remain unclear.

Methods

Using a national cohort of iTTP (n = 368), Shigatoxin-induced hemolytic uremic syndrome (n = 86), atypical hemolytic uremic syndrome (n = 84), and hypertension-related thrombotic microangiopathy (n = 25), we sought to compare the cohort's blood pressure profile to assess its impact on prognosis and diagnostic performances.

Results

Patients with iTTP had lower blood pressure than patients with other TMAs, systolic (130 [interquartile range (IQR) 118-143] vs 161 [IQR 142-180] mmHg) and diastolic (76 [IQR 69-83] vs 92 [IQR 79-105] mmHg, both p < 0.001). The best threshold for iTTP diagnosis corresponded to a systolic blood pressure <150 mmHg. iTTP patients presenting with hypertension had a significantly poorer survival (hazard ratio 1.80, 95% confidence interval 1.07-3.04), and this effect remained significant after multivariable adjustment (hazard ratio = 1.14, 95% confidence interval 1.00-1.30). Addition of a blood pressure criterion modestly improved the French clinical score to predict a severe A disintegrin and metalloprotease with thrombospondin type 1 deficiency in patients with an intermediate score (i.e., either platelet count <30 × 10⁹/L or serum creatinine <200 µM).

Conclusions

Elevated blood pressure at admission affects the prognosis of iTTP patients and may help discriminate them from other TMA patients. Particular attention should be paid to blood pressure and its management in these patients.

Pericardial effusion in giant cell arteritis is associated with increased inflammatory markers: a retrospective cohort study

OBJECTIVE

Giant cell arteritis (GCA) is the most frequent vasculitis affecting adults aged > 50 years. Cardiac involvement in GCA is considered rare, and only a few cases of pericarditis have been reported. The aim of this study was to determine the characteristics and prognosis of GCA patients suffering from pericardial involvement at diagnosis.

METHODS

We conducted a single-centre, retrospective chart review of patients with GCA in internal medicine departments (from 2000 to 2020). Patients were identified through a centralized hospital database. We retrospectively collected demographic, clinicobiological, histological, imaging, treatment and outcome data. Patients with pericardial effusion, defined as an effusion visible on the CT-scan performed at GCA diagnosis were compared to those without pericardial involvement.

RESULTS

Among the 250 patients with GCA, 23 patients (9.2%) had pericardial effusion on CT-scan. The comparison between the groups revealed similar distribution of age, gender, cranial symptoms and ocular ischaemic complications. Patients with pericardial effusion had a higher frequency of weight loss. They also had lower haemoglobin levels and higher platelet levels (p = 0.006 and p = 0.002, respectively), and they more frequently had positive temporal artery biopsy. There were no differences concerning the treatment, relapses, follow-up duration or deaths.

CONCLUSIONS

This case series sheds light on GCA as a cause of unexplained pericardial effusion or symptomatic pericarditis among adults aged > 50 years and elevated inflammatory biological markers. Fortunately, pericardial involvement is a benign GCA manifestation. In that context, the search for constitutional symptoms, cranial symptoms and associated signs of polymyalgia rheumatica is crucial for rapidly guiding GCA diagnosis.

Aortitis is an under-recognized manifestation of antiphospholipid syndrome: A case report and literature review

Aortitis is a classic manifestation of large vessel vasculitis. Antiphospholipid syndrome (APS), sometimes known as Hughes syndrome, is an acquired autoimmune disorder that manifests clinically as recurrent venous or arterial thrombosis. Patients with APS may also suffer from various underlying diseases, most frequently systemic lupus erythematosus (SLE). Catastrophic antiphospholipid syndrome (CAPS) is a rare but serious complication of APS characterized by failure of several organs due to diffuse microcirculatory thrombi. Its main manifestations involve the kidneys, lungs, heart and central nervous system, and require early diagnosis and rapid therapeutic management. While APS can affect virtually any blood vessel, aortitis is not a known symptom of APS. We report the case of a 36-year-old patient with APS and SLE who presented with CAPS during pregnancy, with no concomitant SLE flare. The first manifestation of CAPS was aortitis, preceding renal, cardiac and haematological manifestations. The outcome was favourable with combined treatment including corticosteroids, anticoagulants, plasma exchange and rituximab. We then carried out a literature search for papers describing the presence of aortitis in APS and/or SLE. In the cases of aortic involvement identified in the literature, including another case of CAPS, the occurrence of aortitis in SLE, often associated with the presence of antiphospholipid antibodies/APS, suggests that aortitis should be considered as an under-recognized manifestation and potential non-criterion feature of APS.

Factors associated with dexamethasone efficacy in COVID‐19. A retrospective investigative cohort study

Dexamethasone has demonstrated efficacy in reducing mortality in COVID‐19. However, its practical use is badly defined. We aimed to investigate factors associated with dexamethasone efficacy in real life. Our retrospective study was conducted in two university hospitals between September and November 2020 and included all the consecutive hospitalized patients with a laboratory‐confirmed SARS‐CoV‐2 infection assessed by RT‐PCR, treated with intravenous dexamethasone (6 mg/day). Among 111 patients, 10.6% necessitated a transfer into the intensive care unit (ICU) and the 28‐day mortality rate was 17.1%. The 28‐day mortality rate was significantly lower in patients who demonstrated improvement at 48 h (hazard ratio [HR]: 0.17, 95% confidence interval [CI]: 0.04–0.78, p = 0.02) and 96 h (HR: 0.07, 95% CI: 0.02–0.31, p = 0.0005) after dexamethasone initiation. Apart from well‐known risk factors (age, hypertension, active cancer, severe lesions on chest computed tomography [CT] scan), we found that a high viral load in nasopharyngeal swab (Cycle threshold <30) at dexamethasone initiation was associated with higher 28‐day mortality (66.6% vs. 36.7%, p = 0.03). Patients who did not receive antibiotics at dexamethasone initiation had a higher rate of transfer into the ICU (55.6% vs. 23.5%, p = 0.045) with a trend towards higher mortality in case of severe or critical lesions on CT scan (75.0% vs. 25.0%, p = 0.053). Patients who did not improve within 2–4 days after steroid initiation have a bad prognosis and should receive additional anti‐inflammatory drugs. Our data suggest better efficacy of dexamethasone in patients with a low or negative viral load, receiving broad‐spectrum antibiotics.

At dexamethasone initiation, a high viral load was associated with higher mortality.

Patients without antibiotics were more transferred into the ICU.

Mortality was lower when improvement 48 h and 96 h after dexamethasone initiation.

Mast cells drive pathologic vascular lesions in Takayasu arteritis

BACKGROUND

Takayasu arteritis (TAK) is a large vessel vasculitis resulting in artery wall remodeling with segmental stenosis and/or aneurysm formation. Mast cells (MCs) are instrumental in bridging cell injury and inflammatory response.

OBJECTIVES

This study sought to investigate the contribution of MCs on vessel permeability, angiogenesis, and fibrosis in patients with TAK.

METHODS

MC activation and their tissue expression were assessed in sera and in aorta from patients with TAK and from healthy donors (HDs). In vivo permeability was assessed using a modified Miles assay. Subconfluent cultured human umbilic vein endothelial cells and fibroblasts were used in vitro to investigate the effects of MC mediators on angiogenesis and fibrogenesis.

RESULTS

This study found increased levels of MC activation markers (histamine and indoleamine 2,3-dioxygenase) in sera of patients with TAK compared with in sera of HDs. Marked expression of MCs was shown in aortic lesions of patients with TAK compared with in those of noninflammatory aorta controls. Using Miles assay, this study showed that sera of patients with TAK significantly increased vascular permeability in vivo as compared with that of HDs. Vessel permeability was abrogated in MC-deficient mice. MCs stimulated by sera of patients with TAK supported neoangiogenesis (increased human umbilic vein endothelial cell proliferation and branches) and fibrosis by inducing increased production of fibronectin, type 1 collagen, and α-smooth muscle actin by fibroblasts as compared to MCs stimulated by sera of HD.

CONCLUSIONS

MCs are a key regulator of vascular lesions in patients with TAK and may represent a new therapeutic target in large vessel vasculitis.

High Mortality of HLH in ICU Regardless Etiology or Treatment

Background: Adult hemophagocytic lymphohistiocytosis (HLH) is highly lethal in the ICU. The diagnostic and therapeutic emergency that HLH represents is compounded by its unknown pathophysiological mechanisms. Here, we report on a large cohort of adult HLH in the ICU (ICU-HLH). We analyzed prognostic factors associated with mortality to define the diagnostic and therapeutic challenges in this specific population. Methods: This retrospective study included adult patients diagnosed with HLH in four ICUs in Marseille, France between 2010 and 2020. Patients who fulfilled the HLH-2004 criteria (≥ 4/8) and/or had an HScore ≥ 169 were diagnosed with HLH. HLH was categorized into four groups according to etiology: sepsis-associated HLH, intracellular infection-associated HLH, malignancy-associated HLH, and idiopathic HLH. Results: Two hundred and sixty patients were included: 121 sepsis-associated HLH (47%), 84 intracellular infection-associated HLH (32%), 28 malignancy-associated HLH (11%), and 27 idiopathic HLH (10%). The ICU mortality rate reached 57% (n = 147/260) without a statistical difference between etiological groups. Independent factors associated with mortality in multivariate analysis included age (OR (5 years) = 1.31 [1.16-1.48], p < 0.0001), SOFA score at ICU admission (OR = 1.37 [1.21-1.56], p < 0.0001), degradation of the SOFA score between ICU arrival and HLH diagnosis (Delta SOFA) (OR = 1.47 [1.28-1.70], p < 0.0001), the presence of bone-marrow hemophagocytosis (OR = 5.27 [1.11-24.97], p = 0.04), highly severe anemia (OR = 1.44 [1.09-1.91], p = 0.01), and hypofibrinogenemia (OR = 1.21 [1.04-1.41], p = 0.02). Conclusions: In this large retrospective cohort study of critically ill patients, ICU-HLH in adults was associated with a 57% mortality rate, regardless of HLH etiology or specific treatment. Factors independently associated with prognosis included age, presence of hemophagocytosis in bone-marrow aspirates, organ failure at admission, and worsening organ failure during the ICU stay. Whether a rapid diagnosis and the efficacy of specific therapy improve outcome is yet to be prospectively investigated.

Clinical characteristics and outcomes of patients with haematologic malignancies and COVID-19 suggest that prolonged SARS-CoV-2 carriage is an important issue

Specificities of COVID-19 disease course in patients with haematologic malignancies are still poorly studied. So, we aimed to compare patients with haematologic malignancies to patients without malignancies, matched by sex and age and hospitalised for COVID-19 at the same time and in the same centre. Among 25 patients with haematologic malignancies, we found that mortality (40% versus 4%, p < 0.01), number of days with RT-PCR positivity (21.2 ± 15.9 days [range, 3-57] versus 7.4 ± 5.6 days [range, 1-24], p < 0.01), maximal viral load (mean minimal Ct, 17.2 ± 5.2 [range, 10-30] versus 26.5 ± 5.1 [range, 15-33], p < 0.0001) and the delay between symptom onset and clinical worsening (mean time duration between symptom onset and first day of maximum requirement in inspired oxygen fraction, 14.3 ± 10.7 days versus 9.6 ± 3.7 days, p = 0.0485) were higher than in other patients. COVID-19 course in patients with haematologic malignancies has a delayed onset and is more severe with a higher mortality, and patients may be considered as super-spreaders. Clinicians and intensivists need to be trained to understand the specificity of COVID-19 courses in patients with haematological malignancies.

Anti-NuMA antibodies: clinical associations and significance in patients with primary Sjögren's syndrome or systemic lupus erythematosus

OBJECTIVE

To determine the clinical significance of anti-nuclear mitotic apparatus (NuMA) antibodies (AC-26 or AC-25) in patients with primary Sjögren's syndrome (pSS) and SLE.

METHODS

Between 2013 and 2018, clinical and immunological features of pSS and SLE patients with anti-NuMA antibodies were compared with anti-NuMA antibodies-negative pSS and SLE cohorts.

RESULTS

Among 31 284 sera positive for antinuclear antibodies, 90 patients (0.29%) had anti-AC-26 (anti-NuMA1) and AC-25 (anti-HsEg5) antibodies (73.3% and 26.7%, respectively). Autoimmune diseases, mainly consisting in pSS (28.9%) and SLE (21.1%), were found in 67.8%. Anti-NuMA antibodies represented the unique ANA in 60% and 50% of patients with pSS and SLE patients, respectively. Compared with 137 anti-NuMA-negative pSS patients, 20 anti-NuMA-positive pSS presented with less frequent ocular sicca syndrome (70.0% vs 89.1%, P=0.031), dryness complications (15.0% vs 39.4%, P=0.045), or detectable anti-SSa and/or anti-SSb antibodies (40.0% vs 66.4%, P=0.027). Compared with 80 anti-NuMA-negative SLE patients, 14 anti-NuMA-positive SLE patients had no lupus nephritis (0.0% vs 28.8%, P=0.049), less frequent dsDNA antibodies (42.9% vs 75.0%, P=0.025) and complement consumption (21.4% vs 53.8%, P=0.040). Anti-NuMA-positive pSS and SLE patients less frequently required treatments compared with anti-NuMA-negative patients.

CONCLUSION

Although rare, anti-NuMA antibodies are mainly associated with pSS and SLE and may be useful for diagnosis when other auto-antibodies are negative. PSS and SLE patients with anti-NuMA antibodies have less severe clinical and biological profiles, suggesting that anti-NuMA antibodies may constitute a good prognosis marker in both autoimmune diseases.

Determination of anti-ADAMTS-13 autoantibody titers in ELISA: Influence of ADAMTS-13 presentation and autoantibody detection

BACKGROUND

Immune-mediated thrombotic thrombocytopenic purpura (iTTP) is caused by inhibitory and/or clearing anti-ADAMTS-13 (A Disintegrin and Metalloprotease with ThromboSpondin type 1 repeats, member 13) autoantibodies. To determine the presence and total level of anti-ADAMTS-13 autoantibodies, commercial and in-house developed ELISAs are performed. However, different ELISA methods vary in relation to the presentation of recombinant (r)ADAMTS-13 and the detection method of the anti-ADAMTS-13 autoantibodies. Currently, the influence of those different approaches on anti-ADAMTS-13 autoantibody titers is not known.

OBJECTIVES

To assess the influence of different ADAMTS-13 presentation- and autoantibody detection methods on anti-ADAMTS-13 autoantibody titers in ELISA.

MATERIALS/METHODS

Anti-ADAMTS-13 autoantibody titers from 18 iTTP patients were determined using four different set-ups of anti-ADAMTS-13 autoantibody ELISAs. The ELISAs varied in the used presentation of rADAMTS-13 (directly coated full-length rADAMTS-13, directly coated rMDTCS and rT2C2, or antibody-captured full-length rADAMTS-13) and the detection antibodies (polyclonal anti-human IgG or monoclonal anti-human IgG1-4 antibodies).

RESULTS

Strong correlations between the different anti-ADAMTS-13 autoantibody ELISA approaches were observed, when using polyclonal anti-human IgG detection antibodies recognizing all IgG subclasses similarly, independent of the method of rADAMTS-13 presentation. Anti-ADAMTS-13 autoantibody titers correlated less when using a mixture of monoclonal anti-human IgG1-4 , because not all IgG subclasses were recognized with similar affinities.

CONCLUSION

Anti-ADAMTS-13 autoantibody levels using different methods of rADAMTS-13 presentation strongly correlate. However, the levels of anti-ADAMTS-13 autoantibodies are highly dependent on the detection antibody used, which should detect all IgG subclasses (IgG1-4 ) equally well.

Effect of anakinra on mortality in patients with COVID-19: a systematic review and patient-level meta-analysis

Background

Anakinra might improve the prognosis of patients with moderate to severe COVID-19 (ie, patients requiring oxygen supplementation but not yet receiving organ support). We aimed to assess the effect of anakinra treatment on mortality in patients admitted to hospital with COVID-19.

Methods

For this systematic review and individual patient-level meta-analysis, a systematic literature search was done on Dec 28, 2020, in Medline (PubMed), Cochrane, medRxiv, bioRxiv, and the ClinicalTrials.gov databases for randomised trials, comparative studies, and observational studies of patients admitted to hospital with COVID-19, comparing administration of anakinra with standard of care, or placebo, or both. The search was repeated on Jan 22, 2021. Individual patient-level data were requested from investigators and corresponding authors of eligible studies; if individual patient-level data were not available, published data were extracted from the original reports. The primary endpoint was mortality after 28 days and the secondary endpoint was safety (eg, the risk of secondary infections). This study is registered on PROSPERO (CRD42020221491).

Findings

209 articles were identified, of which 178 full-text articles fulfilled screening criteria and were assessed. Aggregate data on 1185 patients from nine studies were analysed, and individual patient-level data on 895 patients were provided from six of these studies. Eight studies were observational and one was a randomised controlled trial. Most studies used historical controls. In the individual patient-level meta-analysis, after adjusting for age, comorbidities, baseline ratio of the arterial partial oxygen pressure divided by the fraction of inspired oxygen (PaO₂/FiO₂), C-reactive protein (CRP) concentrations, and lymphopenia, mortality was significantly lower in patients treated with anakinra (38 [11%] of 342) than in those receiving standard of care with or without placebo (137 [25%] of 553; adjusted odds ratio [OR] 0·32 [95% CI 0·20-0·51]). The mortality benefit was similar across subgroups regardless of comorbidities (ie, diabetes), ferritin concentrations, or the baseline PaO₂/FiO₂. In a subgroup analysis, anakinra was more effective in lowering mortality in patients with CRP concentrations higher than 100 mg/L (OR 0·28 [95% CI 0·17-0·47]). Anakinra showed a significant survival benefit when given without dexamethasone (OR 0·23 [95% CI 0·12-0·43]), but not with dexamethasone co-administration (0·72 [95% CI 0·37-1·41]). Anakinra was not associated with a significantly increased risk of secondary infections when compared with standard of care (OR 1·35 [95% CI 0·59-3·10]).

Interpretation

Anakinra could be a safe, anti-inflammatory treatment option to reduce the mortality risk in patients admitted to hospital with moderate to severe COVID-19 pneumonia, especially in the presence of signs of hyperinflammation such as CRP concentrations higher than 100 mg/L.

Funding

Sobi.

Quantification of Antifibrillarin (anti-U3 RNP) Antibodies: A New Insight for Patients with Systemic Sclerosis

Background: The detection of additional autoantibodies is of great concern in systemic sclerosis (SSc) when those included in the ACR/EULAR classification are negative. In this context, the interest of antifibrillarin (anti-U3RNP) autoantibodies (AFAs) in the routine evaluation of SSc remains unclear. We aimed to assess the relevance of AFAs and their clinical association in SSc patients. Methods: In a multicenter observational retrospective study, we collected immunological and clinical data associated with AFA positivity in SSc (n = 42) and non-SSc patients (n = 13). Patients with SSc negative for AFAs (n = 83) were considered as a control group. AFAs were detected by indirect immunofluorescence (IIF) using HEp-2 cells, EliA or immunoblot techniques. Results: We confirmed a typical nuclear IIF pattern and showed that AFAs are mostly exclusive towards SSc conventional autoantibodies. Although also observed in non-SSc patients, high levels of AFAs with the ELiA technique allowed the diagnosis of SSc. Compared to AFA-negative SSc patients, AFA-positive SSc patients more frequently exhibited visceral involvements. They more frequently suffered from the diffuse cutaneous form and had a higher global severity of the disease. Conclusions: We demonstrate the usefulness of quantifying AFAs in the immunological exploration of SSc, especially when patients are seronegative for SSc conventional autoantibodies and display a typical IIF pattern. AFAs might constitute an interesting marker of SSc severity.

Discrimination of COVID-19 From Inflammation-Induced Cytokine Storm Syndromes Using Disease-Related Blood Biomarkers

Objective

Infection with the novel coronavirus SARS–CoV‐2 triggers severe illness with high mortality in a subgroup of patients. Such a critical course of COVID‐19 is thought to be associated with the development of cytokine storm, a condition seen in macrophage activation syndrome (MAS) and secondary hemophagocytic lymphohistiocytosis (HLH). However, specific data demonstrating a clear association of cytokine storm with severe COVID‐19 are still lacking. The aim of this study was to directly address whether immune activation in COVID‐19 does indeed mimic the conditions found in these classic cytokine storm syndromes.

Methods

Levels of 22 biomarkers were quantified in serum samples from patients with COVID‐19 (n = 30 patients, n = 83 longitudinal samples in total), patients with secondary HLH/MAS (n = 50), and healthy controls (n = 9). Measurements were performed using bead array assays and single‐marker enzyme‐linked immunosorbent assay. Serum biomarker levels were assessed for correlations with disease outcome.

Results

In patients with secondary HLH/MAS, we observed pronounced activation of the interleukin‐18 (IL‐18)–interferon‐γ axis, increased serum levels of IL‐1 receptor antagonist, intercellular adhesion molecule 1, and IL‐8, and strongly reduced levels of soluble Fas ligand in the course of SARS–CoV‐2 infection. These observations appeared to discriminate immune dysregulation in critical COVID‐19 from the well‐recognized characteristics of other cytokine storm syndromes.

Conclusion

Serum biomarker profiles clearly separate COVID‐19 from MAS or secondary HLH in terms of distinguishing the severe systemic hyperinflammation that occurs following SARS–CoV‐2 infection. These findings could be useful in determining the efficacy of drugs targeting key molecules and pathways specifically associated with systemic cytokine storm conditions in the treatment of COVID‐19.

Excess body weight is an independent risk factor for severe forms of COVID-19

BACKGROUND AND AIMS

Few studies distinguished the independent role of overweight/obesity or their associated-comorbidities in the evolution towards severe forms of COVID-19. Obesity as a unifying risk factor for severe COVID-19 is an emerging hypothesis. The aim of this study was to evaluate whether excessive body weight per se, was a risk factor for developing a severe form of COVID-19.

PATIENTS AND METHODS

We included 131 patients hospitalized for COVID-19 pneumonia in a single center of the internal medicine department in Marseille, France. We recorded anthropometric and metabolic parameters such as fasting glycaemia, insulinemia, HOMA-IR, lipids, and all clinical criteria linked to SARS-CoV-2 infection at the admission. Excess body weight was defined by a BMI ≥ 25 kg/m². The occurrence of a serious event was defined as a high-debit oxygen requirement over 6 L/min, admission into the intensive care unit, or death.

RESULTS

Among 113 patients, two thirds (n = 76, 67%) had an excess body weight. The number of serious events was significantly higher in excess body weight patients compared to normal weight patients (respectively 25% vs 8%, p = 0.03) although excess body weight patients were younger (respectively 63.6 vs 70.3 years old, p = 0.01). In multivariate analyses, the excess body weight status was the only predictor for developing a serious event linked to SARS-CoV-2 infection, with an odds ratio at 5.6 (95% CI: 1.30-23.96; p = 0.02), independently of previous obesity associated comorbidities. There was a trend towards a positive association between the BMI (normal weight, overweight and obesity) and the risk of serious events linked to COVID-19, with a marked increase from 8.1% to 20% and 30.6% respectively (p = 0.05).

CONCLUSION

Excess body weight was significantly associated with severe forms of the disease, independently of its classical associated comorbidities. Physicians and specialists in Public Health must be sensitized to better protect people with an excess body weight against SARS-CoV-2 infection.

French recommendations for the management of Behçet's disease

Behçet's disease (BD) is a systemic variable vessel vasculitis that involves the skin, mucosa, joints, eyes, arteries, veins, nervous system and gastrointestinal system, presenting with remissions and exacerbations. It is a multifactorial disease, and several triggering factors including oral cavity infections and viruses may induce inflammatory attacks in genetically susceptible individuals. BD vasculitis involves different vessel types and sizes of the vascular tree with mixed-cellular perivascular infiltrates and is often complicated by recurrent thrombosis, particularly in the venous compartment. Several new therapeutic modalities with different mechanisms of action have been studied in patients with BD. A substantial amount of new data have been published on the management of BD, especially with biologics, over the last years. These important therapeutic advances in BD have led us to propose French recommendations for the management of Behçet's disease [Protocole National de Diagnostic et de Soins de la maladie de Behçet (PNDS)]. These recommendations are divided into two parts: (1) the diagnostic process and initial assessment; (2) the therapeutic management. Thirty key points summarize the essence of the recommendations. We highlighted the main differential diagnosis of BD according to the type of clinical involvement; the role of genetics is also discussed, and we indicate the clinical presentations that must lead to the search for a genetic cause.

Immunogenic hotspots in the spacer domain of ADAMTS13 in immune-mediated thrombotic thrombocytopenic purpura

BACKGROUND

Immune-mediated thrombotic thrombocytopenic purpura (iTTP) is caused by anti-ADAMTS13 autoantibodies inducing a severe deficiency of ADAMTS13. Epitope mapping studies on samples obtained during acute iTTP episodes have shown that the iTTP immune response is polyclonal, with almost all patients having autoantibodies targeting the spacer domain of ADAMTS13.

OBJECTIVES

To identify the immunogenic hotspots in the spacer domain of ADAMTS13.

PATIENTS/METHODS

A library of 11 full-length ADAMTS13 spacer hybrids was created in which amino acid regions of the spacer domain of ADAMTS13 were exchanged by the corresponding region of the spacer domain of ADAMTS1. Next, the full-length ADAMTS13 spacer hybrids were used in enzyme-linked immunosorbent assay to epitope map anti-spacer autoantibodies in 138 samples from acute and remission iTTP patients.

RESULTS

Sixteen different anti-spacer autoantibody profiles were identified with a similar distribution in acute and remission patients. There was no association between the anti-spacer autoantibody profiles and disease severity. Almost all iTTP samples contained anti-spacer autoantibodies against the following three regions: amino acid residues 588-592, 602-610, and 657-666 (hybrids E, G, and M). Between 31% and 57% of the samples had anti-spacer autoantibodies against amino acid regions 572-579, 629-638, 667-676 (hybrids C, J, and N). In contrast, none of the samples had anti-spacer autoantibodies against amino acid regions 556-563, 564-571, 649-656, and 677-685 (hybrids A, B, L, and O).

CONCLUSION

We identified three hotspot regions (amino acid regions 588-592, 602-610, and 657-666) in the spacer domain of ADAMTS13 that are targeted by anti-spacer autoantibodies found in a large cohort of iTTP patients.

[Endothelial dysfunction in thrombotic thrombocytopenic purpura: therapeutic perspectives]

Immune Thrombotic Thrombocytopenic Purpura (iTTP) is a rare but severe disease with a mortality rate of almost 100 % in the absence of adequate treatment. iTTP is caused by a severe deficiency in ADAMTS13 activity due to the production of inhibitory antibodies. Age has been shown to be a major prognostic factor. iTTP patients in the elderly (60yo and over) have more frequent organ involvement, especially heart and kidney failures compared with younger patients. They also have non-specific neurologic symptoms leading to a delayed diagnosis. Factors influencing this impaired survival among older patients remain unknown so far. Alteration of the functional capacity of involved organs could be part of the explanation as could be the consequences of vascular aging. In fact, severe ADAMTS13 deficiency is necessary but likely not sufficient for iTTP physiopathology. A second hit leading to endothelial activation is thought to play a central role in iTTP. Interestingly, the mechanisms involved in endothelial activation may share common features with those involved in vascular aging, potentially leading to endothelial dysfunction. It could thus be interesting to better investigate the causes of mid- and long-term mortality among older iTTP patients to confirm whether inflammation and endothelial activation really impact vascular aging and long-term mortality in those patients, in addition to their presumed role at iTTP acute phase. If so, further insights into the mechanisms involved could lead to new therapeutic targets.

[Immunosuppressive therapy in severe or chronic pediatric uveitis: Review of the literature]

Immunosuppressants are prescribed for pediatric uveitis in cases of severe involvement affecting the prognosis for vision or life, in cases of recurrent or chronic uveitis to achieve corticosteroid sparing, or in cases of corticosteroid resistance. Immunosuppressants used in children include antimetabolites (methotrexate, mycophenolate mofetil, azathioprine), cyclosporine, tacrolimus, and biologics, including infliximab, adalimumab, anakinra, canakinumab, and tocilizumab. The mechanisms of action and indications of the various immunosuppressants are described in this review.

Circulating Endothelial Cells as a Marker of Endothelial Injury in Severe COVID -19

Beside the commonly described pulmonary expression of the coronavirus disease 2019 (COVID-19), major vascular events have been reported. The objective of this study was to investigate whether increased levels of circulating endothelial cells (CEC) might be associated with severe forms of COVID-19. Ninety-nine patients with COVID-19 were enrolled in this retrospective study. Patients in the intensive care units (ICU) had significantly higher CEC counts than non-ICU patients and the extent of endothelial injury was correlated with putative markers of disease severity and inflammatory cytokines. Altogether, these data provide in vivo evidence that endothelial injury is a key feature of COVID-19.

Axial Articular Manifestations in Primary Sjögren Syndrome: Association With Spondyloarthritis

OBJECTIVE

To assess the prevalence of axial articular manifestations (AAMs) in patients with primary Sjögren syndrome (pSS), to investigate whether these symptoms reveal an associated spondyloarthritis (SpA), and to assess their therapeutic management.

METHODS

Among 148 consecutive patients with pSS fulfilling European League Against Rheumatism (EULAR)/American College of Rheumatology 2019 classification criteria followed between 2010 and 2018, we selected those who presented with AAMs. The association with SpA was retained when patients fulfilled Assessment of SpA international Society criteria.

RESULTS

A total of 29 patients (20%, 28 women) with a median age of 43 years (range 15-65 yrs), were identified. The main extraglandular features were peripheral arthralgia and arthritis in 93% and 90% of patients, respectively. Positive anti-Ro/SSA (anti-SSA) antibody was reported in 62%. AAMs were inaugural in 7%, delayed from the diagnostic of pSS in 7%, and occurred concomitantly in 86% of patients. AAMs were not associated to multisystemic involvement of pSS. Radiographic sacroiliitis was mentioned in 65%, and HLA-B27 was positive in 13%. The diagnosis of SpA was retained in 23/29 patients (79%), among which 74% and 26% fulfilled psoriatic arthritis and ankylosing spondylitis criteria, respectively. There was no phenotypic difference according to the anti-SSA antibody status. With a median follow-up of 60 months (range: 5-96), 61% of patients with associated SpA required biotherapies, mainly of anti-tumor necrosis factor-α or anti-interleukin 17A molecules with a good clinical outcome in 64% and no effect on pSS.

CONCLUSION

AAMs are not uncommon in patients with pSS and may reveal an associated SpA. Treatment of AAMs, especially when clearly associated with SpA, may necessitate biologics, following SpA-management therapeutic guidelines.