Search

Erdheim-Chester disease (ECD) is a rare non-Langerhans cell histiocytosis that frequently infiltrates the peri-kidney space ("hairy kidney" appearance), kidney pelvis and proximal ureters, leading to obstructive uropathy. Here, we analyzed the clinical characteristics, imaging findings and long-term kidney outcome of a large multicenter cohort comprising 195 consecutive patients with ECD. Retroperitoneal peri-kidney or peri-ureteral involvement was detected at diagnosis in 147 patients. Of them, 70 had hydronephrosis (bilateral in 47), and 16 with kidney atrophy (unilateral in 14). Kidney vascular peduncle infiltration was found in 60 patients, and kidney artery stenosis in 31. The estimated glomerular filtration rate (eGFR) at diagnosis was significantly lower in patients with than in those without peri-kidney involvement (median 74 vs. 98 mL/min/1.73 m

Supplementary Figure 1. Somatic mutations detected in histiocytic neoplasms. Supplementary Figure 2. Frequencies of known activating kinase mutations in histiocytic neoplasms. Supplementary Figure 3. ARAF mutations and variants of unknown significance detected in BRAFV600E-wildtype, non-Langerhans Cell Histiocytic neoplasms. Supplementary Figure 4. Clinical and histological images of the non-Langerhans cell histiocytosis (non-LCH) lesions from index patients with kinase fusions identified by RNA-seq. Supplementary Figure 5. Gene expression analysis of histiocytic neoplasms by RNA-seq. Supplementary Table 1. Characteristics of patient samples with histiocytic neoplasms used in this study and genomic analysis utilized for each sample. Supplementary Table 2. Whole exome sequencing metrics. Supplementary Table 3. Somatic variants identified by whole exome and whole transcriptome sequencing and validated by droplet-digital PCR and/or custom-capture targeted next-generation sequencing with variant allele frequencies (VAFs). Supplementary Table 4. List of the top 1% of differentially expressed genes across histiocytic samples from mRNA sequencing. Supplementary Table 5. PCR primers with M13F2 and M13R2 tails (blue) for Sanger sequencing used in the targeted sequencing recurrence testing for MAP2K1 exons 2 and 3 and all coding regions of ARAF.

ImportancePulmonary embolism (PE) is characterized by occlusion of blood flow in a pulmonary artery, typically due to a thrombus that travels from a vein in a lower limb. The incidence of PE is approximately 60 to 120 per 100 000 people per year. Approximately 60 000 to 100 000 patients die from PE each year in the US.ObservationsPE should be considered in patients presenting with acute chest pain, shortness of breath, or syncope. The diagnosis is determined by chest imaging. In patients with a systolic blood pressure of at least 90 mm Hg, the following 3 steps can be used to evaluate a patient with possible PE: assessment of the clinical probability of PE, D-dimer testing if indicated, and chest imaging if indicated. The clinical probability of PE can be assessed using a structured score or using clinical gestalt. In patients with a probability of PE that is less than 15%, the presence of 8 clinical characteristics (age 94%, no recent surgery or trauma, no prior venous thromboembolism event, no hemoptysis, no unilateral leg swelling, and no estrogen use) identifies patients at very low risk of PE in whom no further testing is needed. In patients with low or intermediate clinical probability, a D-dimer level of less than 500 ng/mL is associated with a posttest probability of PE less than 1.85%. In these patients, PE can be excluded without chest imaging. A further refinement of D-dimer threshold is possible in patients aged 50 years and older, and in patients with a low likelihood of PE. Patients with a high probability of PE (ie, >40% probability) should undergo chest imaging, and D-dimer testing is not necessary. In patients with PE and a systolic blood pressure of 90 mm Hg or higher, compared with heparin combined with a vitamin K antagonist such as warfarin followed by warfarin alone, direct oral anticoagulants such as apixaban, edoxaban, rivaroxaban, or dabigatran, are noninferior for treating PE and have a 0.6% lower rate of bleeding. In patients with PE and systolic blood pressure lower than 90 mm Hg, systemic thrombolysis is recommended and is associated with an 1.6% absolute reduction of mortality (from 3.9% to 2.3%).Conclusions and RelevanceIn the US, PE affects approximately 370 000 patients per year and may cause approximately 60 000 to 100 000 deaths per year. First-line therapy consists of direct oral anticoagulants such as apixaban, edoxaban, rivaroxaban, or dabigatran, with thrombolysis reserved for patients with systolic blood pressure lower than 90 mm Hg.

Histiocytoses are heterogeneous hematopoietic diseases characterized by the accumulation of CD68(+) cells with various admixed inflammatory infiltrates. The identification of the pivotal role of the mitogen-activated protein kinase (MAPK) pathway has opened new avenues of research and therapeutic approaches. We review the neurologic manifestations of 3 histiocytic disorders with frequent involvement of the brain and spine: Langerhans cell histiocytosis (LCH), Erdheim-Chester disease (ECD), and Rosai-Dorfman-Destombes disease (RDD). Central nervous system (CNS) manifestations occur in 10%-25% of LCH cases, with both tumorous or neurodegenerative forms. These subtypes differ by clinical and radiological presentation, pathogenesis, and prognosis. Tumorous or degenerative neurologic involvement occurs in 30%-40% of ECD patients and affects the hypothalamic-pituitary axis, meninges, and brain parenchyma. RDD lesions are typically tumorous with meningeal or parenchymal masses with strong contrast enhancement. Unlike LCH and ECD, neurodegenerative lesions or syndromes have not been described with RDD. Familiarity with principles of evaluation and treatment both shared among and distinct to each of these 3 diseases is critical for effective management. Refractory or disabling neurohistiocytic involvement should prompt the consideration for use of targeted kinase inhibitor therapies.

Objectives Excessive and inappropriate production of pro-inflammatory cytokines plays a key role in Still’s disease. Janus kinase inhibitor (JAKi) agents mainly block pro-inflammatory cytokine pathways, notably IL-6 and IFN. The objective was to assess the efficacy and safety of JAKi agents in difficult-to-treat systemic JIA or adult-onset Still’s disease (AOSD). Methods This retrospective study was based on a national survey conducted in the departments of rheumatology, paediatric rheumatology and internal medicine of French hospitals regarding systemic JIA and AOSD patients who received JAKi agents. The data were collected with a standardized questionnaire and analysed at different times (treatment initiation, months 1, 3 and 6 and the end of follow-up). Results Nine patients (seven adults) were included. All patients showed inadequate response to CS or conventional synthetic or biologic DMARDs. Baricitinib was used in five patients, ruxolitinib in two, tofacitinib in two and upadacitinib in one. A JAKi was used combined with CS in all but two patients. A JAKi was associated with anakinra and CS in one patient, and with MTX, anakinra and CS in another. The median (range) follow-up was 16 (1–33) months. Two cases out of nine showed complete remission, 3/9 partial response and 4/9 treatment failure. At the last visit, CS could be decreased but not stopped. Tolerance of the JAKi was acceptable (no severe adverse events). Conclusion JAKi agents may be a therapeutic option for some patients with difficult-to-treat Still’s disease, especially those with partial response to medium- or high-dose CS or biologics.

ObjectivesType-I interferons (IFNs-I) have potent antiviral effects. IFNs-I are also overproduced in patients with systemic lupus erythematosus (SLE). Autoantibodies (AAbs) neutralising IFN-α, IFN-β and/or IFN-ω subtypes are strong determinants of hypoxemic COVID-19 pneumonia, but their impact on inflammation remains unknown.MethodsWe retrospectively analysed a monocentric longitudinal cohort of 609 patients with SLE. Serum AAbs against IFN-α were quantified by ELISA and functionally assessed by abolishment of Madin-Darby bovine kidney cell protection by IFN-α2 against vesicular stomatitis virus challenge. Serum-neutralising activity against IFN-α2, IFN-β and IFN-ω was also determined with a reporter luciferase activity assay. SARS-CoV-2 antibody responses were measured against wild-type spike antigen, while serum-neutralising activity was assessed against the SARS-CoV-2 historical strain and variants of concerns.ResultsNeutralising and non-neutralising anti-IFN-α antibodies are present at a frequency of 3.3% and 8.4%, respectively, in individuals with SLE. AAbs neutralising IFN-α, unlike non-neutralising AAbs, are associated with reduced IFN-α serum levels and a reduced likelihood to develop active disease. However, they predispose patients to an increased risk of herpes zoster and severe COVID-19 pneumonia. Severe COVID-19 pneumonia in patients with SLE is mostly associated with combined neutralisation of different IFNs-I. Finally, anti-IFN-α AAbs do not interfere with COVID-19 vaccine humoral immunogenicity.ConclusionThe production of non-neutralising and neutralising anti-IFN-I antibodies in SLE is likely to be a consequence of SLE-associated high IFN-I serum levels, with a beneficial effect on disease activity, yet a greater viral risk. This finding reinforces the recommendations for vaccination against SARS-CoV-2 in SLE.

Systemic rheumatic diseases (SRDs) are a group of inflammatory disorders that can need intensive care unit (ICU) admission during a flare-up, requiring administration of immunosuppressants. We undertook this study to determine the frequency, outcome, and occurrence associated factors of infections in flare-up SRD patients receiving immunosuppressant.Monocenter, a retrospective study including SRD patients admitted to ICU for a flare-up requiring immunosuppressant from 2004 to 2019. The primary endpoint was in-ICU-acquired infections.Ninety-eight patients (female/male ratio: 1.6; mean age at admission: 39.5 ± 17.4 years) were admitted to the ICU for a SRD flare-up, inaugural in 61.2% cases. A specific treatment was given to every patient: corticosteroids 100%, cyclophosphamide 45.9%, plasma exchange 46.9%. Ninety-five infections occurred in 35 (36%) patients mainly pneumonias. The overall in-hospital mortality was 17.3%, and 46% of patients with a nosocomial infection died during their ICU stay. The logistic regression multivariable model retained renal replacement therapy and mechanical ventilation as independent predictors of infection.In-ICU-acquired infection in SRD flare-up is a frequent event associated with organ failures but not with in-ICU use of immunosuppressants. These data suggest that the fear of infection should not withhold a careful in-ICU use of immunosuppressive drugs. Key Points • In-ICU infections are frequent in flare-up systemic rheumatic disease patients. • Infections are associated with increased mortality. • Cyclophosphamide given in ICU was not independently associated with infection. • Severe neutropenia occurred in 27% of patients receiving cyclophosphamide in ICU.

Langerhans cell histiocytosis (LCH) is a rare inflammatory myeloid neoplasm characterized by proliferation of tumor histiocytes that involves multiple organs including central nervous system. The physiopathologic process underlying degenerative neuro-LCH (i.e., DN-LCH) remains imperfectly settled. Since the main clinical features of DN-LCH are cerebellar ataxia and dysexecutive syndrome, eye movements might be disrupted and may help in disease diagnosis and monitoring. We retrospectively analyzed the medical records of twenty DN-LCH patients investigated using eye movement recording (EMR) in our hospital between 2015 and 2018. DN-LCH patients exhibited (i) abnormal gain in visually guided saccades including hypermetric saccades and excessive gain variability -45.0%-, (ii) increased mean antisaccade error rates -66.7%-, (iii) altered smooth pursuit -50.0%-, and (iv) excessive number of square wave jerks-25%- and gaze-evoked nystagmus. Our study suggests that DN-LCH patients present a peculiar pattern of eye movement impairments supporting cerebellar and prefrontal dysfunctions. As a non-invasive method, EMR could therefore be a useful tool for quantitative monitoring of DN-LCH patients. Further studies are warranted to support our findings.

International audience; Aim: To present the first case series of patients with Langerhans cell histiocytosis (LCH) also affected by Crohn's disease (CD), both of which are granulomatous diseases, and in LCH investigate the role of interleukin (IL)-23, which is a well-described disease mediator in CD.Methods: A case series of three patients with LCH and CD were described; a cohort of LCH patients (n = 55) as well as controls (n = 55) were analysed for circulating IL-23 levels; and the relation between the percentage of LCH cells in lesions and circulating IL-23 levels was analysed in seven LCH patients.Results: Differential diagnostic challenges for these two granulomatous diseases were highlighted in the case series, and it took up to 3 years to diagnose CD. Elevated IL-23 levels were found in LCH patients. The amount of lesional LCH cells correlated with the levels of circulating IL-23.Conclusion: Both CD and LCH should be considered in patients with inflammatory gastrointestinal involvement. The IL-23 pathway is a common immunological trait between these two granulomatous diseases.

Erdheim-Chester disease (ECD) is a rare histiocytosis that was recently recognized as a neoplastic disorder owing to the discovery of recurrent activating MAPK (RAS-RAF-MEK-ERK) pathway mutations. Typical findings of ECD include central diabetes insipidus, restrictive pericarditis, perinephric fibrosis, and sclerotic bone lesions. The histopathologic diagnosis of ECD is often challenging due to nonspecific inflammatory and fibrotic findings on histopathologic review of tissue specimens. Additionally, the association of ECD with unusual tissue tropism and an insidious onset often results in diagnostic errors and delays. Most patients with ECD require treatment, except for a minority of patients with minimally symptomatic single-organ disease. The first ECD consensus guidelines were published in 2014 on behalf of the physicians and researchers within the Erdheim-Chester Disease Global Alliance. With the recent molecular discoveries and the approval of the first targeted therapy (vemurafenib) for BRAF-V600–mutant ECD, there is a need for updated clinical practice guidelines to optimize the diagnosis and treatment of this disease. This document presents consensus recommendations that resulted from the International Medical Symposia on ECD in 2017 and 2019. Herein, we include the guidelines for the clinical, laboratory, histologic, and radiographic evaluation of ECD patients along with treatment recommendations based on our clinical experience and review of literature in the molecular era.

Langerhans cell histiocytosis (LCH) is a rare protean disease that usually affects children. Few data are available for management of adult-onset cases. A complete picture of the efficacy and safety of 2CdA (2-chlorodeoxyadenosine, cladribine) is lacking. We report a retrospective multicentre study of 23 adult LCH (a-LCH) patients who received single-agent 2CdA and a systematic literature review. All had previously received systemic therapy (vinblastine, n = 19). Response to 2CdA was evaluable in 22 cases. Overall response rate (ORR) was 91%. Complete response (CR) occurred in 11 cases (50%). Nine patients (39%) developed grade 3-4 neutropenia and/or severe infection. A literature review yielded 48 additional cases. A pooled analysis confirmed our findings (ORR: 88%, CR: 49%). CRs were rare with cumulative dose

Poster: "ESTI 2019 / P-0109 / Lung involvement in Destombes-Rosai-Dorfman disease: clinical and radiological features, and response to the MEK inhibitor cobimetinib " by: "Q. moyon, S. Boussouar , F. cohen aubart, P. maksud, N. Aladjidi, G. Prevot, J. donadieu, Z. amoura, P. A. Grenier, J. haroche; Paris/FR"

Objective Data on severe heart valve disease (HVD), including Libman–Sacks endocarditis, associated with SLE and/or APS requiring valvular surgery are scarce. We thus conducted a retrospective study, aimed at describing and clarifying clinical, laboratory, echocardiographic, histopathological and evolutional features of SLE and/or APS patients with severe associated-HVD. Methods An observational retrospective multicentric analysis of 23 adults with SLE and/or APS and HVD between 1996 and 2019 and available histopathological report evaluating long-term follow-up. Results Twenty-three individuals (20 females, median age 37 [range 17–76] years) were included. All had APS (thrombotic in 22, with an arterial phenotype in 15 and with catastrophic APS [CAPS] in six), and 11 (47%) had SLE. Systemic underlying disease had been diagnosed prior to HVD in 12 (52%). In 10 patients (43%), HVD was complicated by cerebral stroke prior to surgery. Twenty patients (87%) had only one pathological valve, the mitral valve in 18 patients (78%). Valvular thickening (n = 19) and valvular regurgitation (n = 19) were the most frequently reported lesions. Fifteen (62%) patients underwent mechanical valve replacement, six (26%) conservative valve repair (five were later re-operated after a median time of 1 [0–4] year), and two (9%) underwent biological valve replacement. Nine patients (39%) presented early-onset post-operative complications, including three CAPS immediately after surgery and one death. After surgery, 18 patients (78%) had normal postoperative valvular function, but almost half of the patients (43%) had post-operative neurological sequelae (median follow-up of 6 [2–20] years). Conclusion Severe HVD leading to surgery was strongly associated with thrombotic APS, especially arterial phenotypes. Half of the reported patients presented cerebral stroke complicating the HVD. Valvular surgery carried a significant risk of CAPS.

International audience; Background: The systemic capillary leak syndrome (SCLS), also known as Clarkson disease, is a very rare condition characterized by recurrent life-threatening episodes of vascular hyperpermeability in the presence of a monoclonal gammopathy. Extended intravenous immunoglobulin (IVIG) treatment is associated with fewer recurrences and improved survival, but the optimal treatment dosage and duration remain unknown. Objective: We aim to evaluate the safety of IVIG tapering and withdrawal in patients with SCLS. Methods: We conducted a retrospective multicenter study including all adult patients with monoclonal gammopathy–associated SCLS from the EurêClark registry who received at least 1 course of IVIG. The primary end point was overall survival according to IVIG withdrawal. Results: Fifty-nine patients of mean ± SD age 51 ± 13 years were included. Overall cumulative probabilities of 2-, 5-, 10- and 15-year survival were 100%, 85%, 72%, 44%, respectively. The IVIG was withdrawn at least once in 18 patients (31%; W+ group) and never in 41 patients (69%; W– group). Cumulative probabilities of 10-year survival in W+ versus W– groups were 50% and 83% (log rank test, P = .02), respectively. Relapse rate and the median number of relapses in the W+ versus the W– groups were 72% versus 58% (P = 0.3) and 2.5 (0.3–4) versus 1 (0–2) (P = .03), respectively. The IVIG tapering was not statistically associated with increased person-year incidence of attacks using a mixed linear model. Conclusions: The IVIG withdrawal was associated with increased mortality and higher rate of recurrence in SCLS patients. The IVIG tapering might be cautiously considered in stable SCLS patients.

RFC1-CANVAS and primary Sjögren syndrome (pSS) are among the most frequent causes of sensory ganglionopathy (SG) and can present simultaneously in a given patient, sharing confounding signs and symptoms. We describe the clinical characteristics of patients with SG due to CANVAS who were suspected of having or had received a previous diagnosis of pSS.Patients with SG and a genetically confirmed RFC1-CANVAS followed in our centre were ascertained and their personal history of pSS was collected.Among the 71 patients with CANVAS, six patients (all females) had been diagnosed with pSS by their clinicians. In these six patients, the mean age at onset of the SG was 61 years, four patients describing gait instability and positive sensory symptoms, one only gait instability and one only positive sensory symptoms. Five patients had a history of chronic cough; signs at examination included a cerebellar syndrome (n = 3), vestibulopathy (n = 2), pes cavus (n = 3) and dysautonomia (n = 2). On neurophysiological examination, SG was generally severe and symmetrical. All patients presented a sicca syndrome, but only four patients had a confirmed pSS as per 2016 ACR-EULAR classification criteria. Four patients were treated but did not respond to immunosuppressive therapy, one suffering from side effects.The suspicion or diagnosis of pSS in a patient with SG should not exclude RFC1 expansion analysis, as a CANVAS diagnosis may dissuade the clinician from initiating or continuing immunosuppressive therapy, especially in unconfirmed pSS patients. Importantly, a sicca syndrome may lead to pSS misdiagnosis.

ObjectivesTo compare the efficacy to prevent flares of maintenance versus withdrawal of 5 mg/day prednisone in systemic lupus erythematosus (SLE) patients with clinically quiescent disease.MethodsA monocentric, 12-month, superiority, open-label, randomised (1:1) controlled trial was conducted with 61 patients continuing 5 mg/day prednisone and 63 stopping it. Eligibility criteria were SLE patients who, during the year preceding the inclusion, had a clinically inactive disease and a stable SLE treatment including 5 mg/day prednisone. The primary endpoint was the proportion of patient experiencing a flare defined with the SELENA-SLEDAI flare index (SFI) at 52 weeks. Secondary endpoints included time to flare, flare severity according to SFI and British Isles Lupus Assessment Group (BILAG) index and increase in the Systemic Lupus International Collaborating Clinics (SLICC) damage index (SDI).ResultsProportion of patients experiencing a flare was significantly lower in the maintenance group as compared with the withdrawal group (4 patients vs 17; RR 0.2 (95% CI 0.1 to 0.7), p=0.003). Maintenance of 5 mg prednisone was superior with respect to time to first flare (HR 0.2; 95% CI 0.1 to 0.6, p=0.002), occurrence of mild/moderate flares using the SFI (3 patients vs 12; RR 0.2 (95% CI 0.1 to 0.8), p=0.012) and occurrence of moderate/severe flares using the BILAG index (1 patient vs 8; RR 0.1 (95% CI 0.1 to 0.9), p=0.013). SDI increase and adverse events were similar in the two treatment groups. Subgroup analyses of the primary endpoint by predefined baseline characteristics did not show evidence of a different clinical response.ConclusionMaintenance of long term 5 mg prednisone in SLE patients with inactive disease prevents relapse.Trial registration numberNCT02558517; Results

ObjectiveTo report on a large series of patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) and bronchiectasis, with a specific focus on the timeline of occurrence of both features.MethodsRetrospective nationwide multicenter study of patients diagnosed with both AAV and bronchiectasis.ResultsSixty-one patients were included, among whom 27 (44.25%) had microscopic polyangiitis (MPA), 27 (44.25%) had granulomatosis with polyangiitis (GPA), and 7 (11.5%) had eosinophilic GPA. Thirty-nine (64%) had myeloperoxidase (MPO)-ANCA and 13 (21%) had proteinase 3–ANCA. The diagnosis of bronchiectasis either preceded (n = 25; median time between both diagnoses: 16 yrs, IQR 4–54 yrs), was concomitant to (n = 12), or followed (n = 24; median time between both diagnoses: 1, IQR 0–6 yrs) that of AAV. Patients in whom bronchiectasis precedes the onset of AAV (B-AAV group) have more frequent mononeuritis multiplex, MPA, MPO-ANCA, and a 5-fold increase of death. The occurrence of an AAV relapse tended to be protective against bronchiectasis worsening (HR 0.6, 95% CI 0.4–0.99, P = 0.049), while a diagnosis of bronchiectasis before AAV (HR 5.8, 95% CI 1.2–28.7, P = 0.03) or MPA (HR 18.1, 95% CI 2.2–146.3, P = 0.01) were associated with shorter survival during AAV follow-up.ConclusionThe association of bronchiectasis with AAV is likely not accidental and is mostly associated with MPO-ANCA. Patients in whom bronchiectasis precedes the onset of AAV tend to have distinct clinical and biological features and could carry a worse prognosis.

Introduction Systemic rheumatic diseases (SRDs) are a group of inflammatory disorders that can require intensive care unit (ICU) admission because of multiorgan involvement with end-organ failure(s), whose may need a VA- or VV-ECMO support. Data focusing on ECMO in SRD patients are scarce and many questions persist. We undertook this study to determine the outcomes and unfavorable outcome-associated factors of severely ill SRD patients requiring ECMO support. Materials and methods This French monocenter, retrospective study included all SRD patients requiring venovenous (VV)- or venoarterial (VA)-ECMO admitted to a 26-bed ECMO-dedicated ICU from January 2006 to February 2020. The primary endpoint was in-hospital mortality. The secondary outcomes included patient's characteristics (laboratory findings, in-ICU organ-failure treatment(s), SRD-specific manifestations and treatment(s), complications). Were compared the primary and secondary outcomes for the entire population and in the following subgroups : flare-/infection-related admission and VA/VV-ECMO. Results Ninety patients (male/female ratio : 0.5 ; mean age at admission : 41.6 ± 15.2 years) admitted to the ICU received VA/VV-ECMO, respectively, for an SRD-related flare (n = 69, n = 38/31) or infection (n = 21, n = 10/11). The flow chart reports patients’ outcomes according to the reason for admission and ECMO hook-up. SRD was diagnosed in-ICU for 31 (34.4 %) patients. In-ICU and in-hospital mortality rates were 48.9 % and 51.1%, respectively. Nine patients were bridged to cardiac (n = 5) or lung transplantation (n = 4), or left ventricular assist device (n = 2). The Cox multivariable model retained the following independent predictors of in-hospital mortality : in-ICU SRD diagnosis, day-0 Simplified Acute Physiology Score (SAPS) II score ≥ 70 and arterial lactate ≥ 7.5 mmol/L for VA-ECMO–treated patients ; day-0 SAPS II score ≥ 70, ventilator-associated pneumonia and arterial lactate ≥ 7.5 mmol/L for VV-ECMO–treated patients whereas vasculitis independently predicts hospital survey. Conclusion/Discussion The main analysis considered VA- and VV-ECMO patients jointly. The reasons for ICU admissions and ECMO canulation, and the characteristics, management and outcomes of these patients obviously differ. However, the analysis aimed to present a comprehensive, real-life picture of ECMO treatment of SRD patients, with separate analyses of VA- and VV-ECMO subgroups thereafter. Conclusion ECMO support appears to be relevant for critically ill SRD patients, with 49% survival at hospital discharge. Herein, we report the largest series of ECMO-treated, severely ill SRD patients. Vasculitis was independently associated with favorable outcomes of VV-ECMO–treated patients. Further studies are needed to specify the role of ECMO for SRD patients.

This cohort study estimates the prevalence of nonretroperitoneal abdominal organ involvement in Erdheim-Chester disease in a large cohort of patients.

Erdheim–Chester disease is a rare histiocytosis characterized by iconic features associated with compatible histology. Most patients have somatic mutations in the MAP-kinase pathway gene, and the mutations occur in CD14+ monocytes. Differentiation of the myeloid lineage plays a central role in the pathogenesis of histiocytosis. Monocytes are myeloid-derived white blood cells, divided into three subsets, but only the CD14++CD16− “classical monocyte” can differentiate into dendritic cells and tissue macrophages. Since most mutations occur in CD14+ cells and since ECD patients have a particular monocytic phenotype resembling CMML, we studied the correlation between disease activity and monocytic subset distribution during the course of a severe vascular form of ECD requiring liver transplantation. During early follow-up, increased CD14++CD16− “classical monocyte” associated with decreased CD14lowCD16++ “non-classical monocyte” correlated with disease activity. Further studies are needed to confirm the use of monocyte as a marker of disease activity in patients with ECD.

International audience; Inorganic antigens may contribute to paediatric sarcoidosis. Thirty-six patients matched with 36 healthy controls as well as a group of 21 sickle-cell disease (SCD) controls answered an environmental questionnaire. Patients' indirect exposure to inorganic particles, through coresidents' occupations, was higher than in healthy and SCD controls (median score: 2.5 (0.5-7) vs 0.5 (0-2), p=0.003 and 1 (0-2), p=0.012, respectively), especially for construction, exposures to metal dust, talc, abrasive reagents and scouring products. Wood or fossil energies heating were also linked to paediatric sarcoidosis. This study supports a link between mineral environmental exposure due to adult coresident occupations and paediatric sarcoidosis.

Aims Cardiac involvement of Erdheim–Chester disease (ECD), a rare L group histiocytosis, has been reported to be associated with poor outcomes, but systematic studies are lacking. The present study aimed to investigate the prevalence, clinical features, imaging features, and prognosis of cardiac involvement in ECD in a large series. Methods and results All patients with ECD who underwent cardiac magnetic resonance (CMR) imaging between 2003 and 2019 at a French tertiary center were retrospectively included. Primary outcome was all-cause mortality. Secondary outcomes were pericarditis, cardiac tamponade, conduction disorders, device implantation and coronary artery disease (CAD). A total of 200 patients were included [63 (54–71) years, 30% female, 58% BRAFV600E mutated]. Median follow-up was 5.5 years (3.3–9 years). On CMR, right atrioventricular sulcus infiltration was observed in 37% of patients, and pericardial effusion was seen in 24% of patients. In total, 8 patients (4%) had pericarditis (7 acute, 1 constrictive), 10 patients (5%) had cardiac tamponade, 5 patients (2.5%) had ECD-related high-degree conduction disorders, and 45 patients (23%) had CAD. Overall, cardiac involvement was present in 96 patients (48%) and was associated with BRAFV600E mutation [Odds ratio (OR) = 7.4, 95% confidence interval (CI) (3.5–16.8), P < 0.001] and ECD-related clinical events [OR = 5, 95%CI (1.5–21.2), P = 0.004] but not with lower survival in multivariate analysis [adjusted hazard ratio (HR) = 1.4, 95% CI (0.8–2.5), P = 0.2]. Conclusion Cardiac involvement is present in nearly half of ECD patients and is associated with BRAFV600E mutation and complications (pericarditis, cardiac tamponade, and conduction disorders) but not with lower survival.