Search

ZusammenfassungDie Granulomatose mit Polyangiitis (GPA) und mikroskopische Polyangiitis (MPA) sind zwei zur ANCA-assoziierten Vaskulitis (AAV) zählende Entitäten. Beiden Erkrankungen liegt eine systemische nekrotisierende Kleingefäßvaskulitis zugrunde, die jedes Organ betreffen kann. Bei der GPA ist zusätzlich eine in der Regel den Respirationstrakt betreffende extravaskuläre nekrotisierende granulomatöse Entzündung vorzufinden. Das klinische Bild wird in der Mehrzahl der Fälle durch ein pulmo-renales Syndrom mit alveolärer Hämorrhagie und rapid-progressiver Glomerulonephritis sowie weitere Organmanifestationen bestimmt. Bei der GPA imponiert zudem die fast regelhafte Mitbeteiligung des oberen Respirationstrakts. Die GPA ist mit Anti-Neutrophilen zytoplasmatischen Autoantikörpern (ANCA) mit einer Spezifität für die Proteinase 3 (PR3-ANCA) und die MPA für Myeloperoxidase (MPO-ANCA) assoziiert. Die immunsuppressive Therapie richtet sich nach der Krankheitsaktivität und Schwere der Organbeteiligung.

ObjectiveTo develop and validate revised classification criteria for granulomatosis with polyangiitis (GPA).MethodsPatients with vasculitis or comparator diseases were recruited into an international cohort. The study proceeded in five phases: (1) identification of candidate criteria items using consensus methodology, (2) prospective collection of candidate items present at the time of diagnosis, (3) data-driven reduction of the number of candidate items, (4) expert panel review of cases to define the reference diagnosis and (5) derivation of a points-based risk score for disease classification in a development set using least absolute shrinkage and selection operator logistic regression, with subsequent validation of performance characteristics in an independent set of cases and comparators.ResultsThe development set for GPA consisted of 578 cases of GPA and 652 comparators. The validation set consisted of an additional 146 cases of GPA and 161 comparators. From 91 candidate items, regression analysis identified 26 items for GPA, 10 of which were retained. The final criteria and their weights were as follows: bloody nasal discharge, nasal crusting or sino-nasal congestion (+3); cartilaginous involvement (+2); conductive or sensorineural hearing loss (+1); cytoplasmic antineutrophil cytoplasmic antibody (ANCA) or anti-proteinase 3 ANCA positivity (+5); pulmonary nodules, mass or cavitation on chest imaging (+2); granuloma or giant cells on biopsy (+2); inflammation or consolidation of the nasal/paranasal sinuses on imaging (+1); pauci-immune glomerulonephritis (+1); perinuclear ANCA or antimyeloperoxidase ANCA positivity (−1); and eosinophil count ≥1×109 /L (−4). After excluding mimics of vasculitis, a patient with a diagnosis of small- or medium-vessel vasculitis could be classified as having GPA if the cumulative score was ≥5 points. When these criteria were tested in the validation data set, the sensitivity was 93% (95% CI 87% to 96%) and the specificity was 94% (95% CI 89% to 97%).ConclusionThe 2022 American College of Rheumatology/European Alliance of Associations for Rheumatology classification criteria for GPA demonstrate strong performance characteristics and are validated for use in research.

The term "vasculitis" refers to a group of rare immune-mediated diseases characterized by the dysregulated immune system attacking blood vessels located in any organ of the body, including the skin, lungs, and kidneys. Vasculitides are classified according to the size of the vessel that is affected. Although this observation is not specific to small-, medium-, or large-vessel vasculitides, patients show a high circulating neutrophil-to-lymphocyte ratio, suggesting the direct or indirect involvement of neutrophils in these diseases. As first responders to infection or inflammation, neutrophils release cytotoxic mediators, including reactive oxygen species, proteases, and neutrophil extracellular traps. If not controlled, this dangerous arsenal can injure the vascular system, which acts as the main transport route for neutrophils, thereby amplifying the initial inflammatory stimulus and the recruitment of immune cells. This review highlights the ability of neutrophils to "set the tone" for immune cells and other cells in the vessel wall. Considering both their long-established and newly described roles, we extend their functions far beyond their direct host-damaging potential. We also review the roles of neutrophils in various types of primary vasculitis, including immune complex vasculitis, anti-neutrophil cytoplasmic antibody-associated vasculitis, polyarteritis nodosa, Kawasaki disease, giant cell arteritis, Takayasu arteritis, and Behçet's disease.

To examine concentrations of circulating antibodies targeting C3a and C5a complement receptors in ANCA-associated vasculitis (AAV) and analyze their association with disease activity.Concentrations of antibodies against C3a and C5a complement receptors and plasma complement fragments C3a and C5a were determined in patients with AAV (n = 110; granulomatosis with polyangiitis [GPA, n = 82], microscopic polyangiitis [MPA, n = 28]), systemic lupus erythematosus as disease control (SLE, n = 36) and healthy donors (HD, n = 220). C3aR and C5aR expression by circulating neutrophils, monocytes and T cells was analyzed using flow cytometry. Clinical data were assessed at time of serum sampling and during follow-up for 60 months.In AAV, anti-C3aR and anti-C5aR antibodies were decreased (P = 0.0026 and ≤ 0.0001, respectively). In remission, anti-C3aR antibody concentrations rose to values comparable to HD, whereas anti-C5aR antibody concentrations did not. In GPA, C5a and anti-C5aR antibody concentrations inversely correlated with each other (r = -0.6831, P = 0.0127). In newly diagnosed GPA, decreased concentrations of anti-C5aR antibodies but not anti-C3aR antibodies were associated with disease activity (P = 0.0009). Moreover, low anti-C5aR antibodies were associated with relapse in GPA (HR: 3.54, P = 0.0009) and MPA (HR: 4.41, P = 0.0041). The frequency of C5aR-expressing cells within T cell populations was increased in GPA (CD4+ T cells: P = 0.0021; CD8+ T cells: P = 0.0118), but not in MPA.Low concentrations of anti-C5aR antibodies reflect disease activity and are associated with an increased risk for relapse in AAV. This article is protected by copyright. All rights reserved.

Background One key pathological finding in giant cell arteritis (GCA) is the presence of interferon-gamma and interleukin (IL)-17 producing T helper (Th) 1 and Th17 cells in affected arteries. There is anecdotal evidence of successful induction and maintenance of remission with the monoclonal anti-IL-17A antibody secukinumab. Inhibition of IL-17A could therefore represent a potential new therapeutic option for the treatment of GCA. Methods This is a randomized, parallel-group, double-blind, placebo-controlled, multi-center, phase II study in which patients, treating physicians, and the associated clinical staff as well as the sponsor clinical team are blinded. It is designed to evaluate efficacy and safety of secukinumab compared to placebo in combination with an open-label prednisolone taper regimen. Patients included are naïve to biological therapy and have newly diagnosed or relapsing GCA. Fifty patients are randomly assigned in a 1:1 ratio to receive either 300 mg secukinumab or placebo subcutaneously at baseline, weeks 1, 2 and 3, and every 4 weeks from week 4. Patients in both treatment arms receive a 26-week prednisolone taper regimen. The study consists of a maximum 6-week screening period, a 52-week treatment period (including the 26-week tapering), and an 8-week safety follow-up, with primary and secondary endpoint assessments at week 28. Patients who do not achieve remission by week 12 experience a flare after remission or cannot adhere to the prednisolone tapering will enter the escape arm and receive prednisolone at a dose determined by the investigator’s clinical judgment. The blinded treatment is continued. Two optional imaging sub-studies are included (ultrasound and contrast-media enhanced magnetic resonance angiography [MRA]) to assess vessel wall inflammation and occlusion before and after treatment. The primary endpoint is the proportion of patients in sustained remission until week 28 in the secukinumab group compared to the proportion of patients in the placebo group. A Bayesian approach is applied. Discussion The trial design allows the first placebo-controlled data collection on the efficacy and safety of secukinumab in patients with GCA. Trial registration ClinicalTrials.gov NCT03765788. Registration on 5 December 2018, prospective registration, EudraCT number 2018-002610-12; clinical trial protocol number CAIN457ADE11C.

Vasculitides are inflammatory diseases of blood vessels caused by autoimmune or infectious processes, which are associated with alterations and destruction of the vascular wall. From a histopathological point of view, granulomatous vasculitides can be distinguished from necrotizing vasculitides with respect to the pattern of inflammation. Granulomatous vasculitides are characterized by intramural, predominantly lymphohistiocytic infiltrates with the formation of giant cells. They include giant cell arteritis (GCA) and Takayasu arteritis (TAK). By contrast, anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV) belongs to the group of necrotizing vasculitides. AAV includes granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA). In addition to systemic necrotizing small vessel vasculitis, GPA and EGPA are characterized by extravascular granulomatous necrotizing inflammation mainly affecting the upper and/or lower respiratory tract, in EGPA with eosinophilic infiltrates. These granulomatous lesions are part of the autoimmune process and associated with tissue damage.Bei den Vaskulitiden handelt es sich um entzündliche Erkrankungen von Blutgefäßen, hervorgerufen durch autoimmune oder infektiöse Prozesse, die mit einer Alteration und Zerstörung der Gefäßwand einhergehen. Unter histopathologischen Gesichtspunkten werden hinsichtlich des Entzündungsmusters granulomatöse von nekrotisierenden Vaskulitiden unterschieden. Granulomatöse Vaskulitiden zeichnen sich durch intramurale vorwiegend lymphohistiozytäre Infiltrate mit Ausbildung von Riesenzellen aus. Hierzu zählen die Riesenzellarteriitis (RZA) sowie Takayasu-Arteriitis (TAK). Demgegenüber zählt die Anti-Neutrophile zytoplasmatische Autoantikörper(ANCA)-assoziierte Vaskulitis (AAV) zur Gruppe der nekrotisierenden Vaskulitiden. Die AAV umfasst die Granulomatose mit Polyangiitis (GPA), mikroskopische Polyangiitis (MPA) und eosinophile Granulomatose mit Polyangiitis (EGPA). Die GPA und EGPA sind neben der systemischen nekrotisierenden Kleingefäßvaskulitis durch eine extravaskuläre granulomatöse nekrotisierende Entzündung charakterisiert, die hauptsächlich den oberen und/oder unteren Respirationstrakt betrifft, bei EGPA überdies mit eosinophiler Komponente. Die granulomatösen Läsionen sind Teil des autoimmunen Prozesses und gehen mit Gewebsschäden einher.

Objective ANCA-associated vasculitides (AAV) are rare, potentially life-threatening autoimmune diseases characterized by systemic inflammation and organ damage. AAV prevalence rates reported in Europe vary considerably and robust data sources are often lacking. This study aimed to examine the feasibility of claims data analysis as a complementary method to registry-based studies to assess the epidemiology of AAV. Methods In this retrospective observational study, anonymized longitudinal claims data from years 2013–2016 from German statutory health insurance companies (data source: InGef, Institute for Applied Health Research) have been analysed on an age- and gender-stratified cohort of ∼3 million persons representative of the German population. In this cohort, granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA) patients were identified. Results The study cohort revealed a prevalence for GPA and MPA of 210 and 46 cases per million people, respectively. The annual incidence comprised 34 GPA cases and 13 MPA cases per million people per year. Hence, 17 500 AAV patients (GPA and MPA) are estimated to live in Germany, with an annual increase of 3200 patients. According to their demographic and disease-specific characteristics, AAV patients identified in this claims data approach are representative. Conclusion This is the first study using claims data to assess the epidemiology of AAV. In Germany, AAV was diagnosed more frequently than it was estimated by previous self-reporting registry-based studies. The findings indicate that epidemiological data of AAV may have been underestimated but may also reflect improved diagnostic methods and disease recognition.

We present the case of a patient with granulomatous endocarditis of the mitral valve leading to severe valve stenosis caused by granulomatosis with polyangiitis. Endocarditis is a rare complication of granulomatosis with polyangiitis that may be misdiagnosed as infectious endocarditis or, as in our case, thrombotic lesions. (Level of Difficulty: Intermediate.), Graphical abstract

Zu den Grosgefasvaskulitiden zahlen 2 unterschiedliche Entitaten, die Riesenzellarteriitis (RZA) und die Takayasu-Arteriitis (TAK). Die RZA ist die haufigste Vaskulitis in Mitteleuropa und manifestiert sich im Alter von uber 50 Jahren, wohingegen die wesentlich seltenere TAK fast ausschlieslich junge Erwachsene und hierbei uberwiegend Frauen betrifft. Beide Vaskulitiden betreffen als granulomatose Arteriitiden hauptsachlich die Aorta und von ihr abgehende Arterienaste. RZA und TAK sind mit unterschiedlichen Genen des Haupthistokompatibilitatskomplexes assoziiert. Infektionen spielen moglicherweise eine Rolle bei der Initiierung von Grosgefasvaskulitiden. Die Aktivierung von dendritischen Zellen in der Adventitia induziert eine Chemokin- und Zytokin-vermittelte Rekrutierung und Reifung von T‑Helfer(Th)1- und Th17-Zellen und von Zytokin‑, Wachstumsfaktor- und Matrixmetalloproteinase-produzierenden Makrophagen. Bei der RZA werden uberwiegend CD4+-T-Helferzellen und Makrophagen im entzundlichen Infiltrat gefunden, bei der TAK auch zytotoxische CD8+-T-Zellen und γδ-T-Zellen. Dies konnte auf unterschiedliche antigene Trigger bei der RZA und TAK deuten. Die entzundliche Infiltration mit T‑Zellen und Makrophagen sowie die Aktivierung von Myofibroblasten und glatten muskularen Zellen fuhren zu vaskularen Umbauvorgangen mit Intimahyperplasie und Destruktion der Media. Der Umbau ist histologisch durch eine fortschreitende Arterienwandfibrose, Gefasstenosierung und Obstruktion gekennzeichnet. Zusammengefasst stellen die RZA und TAK zwei verschiedene Entitaten mit unterschiedlichem HLA(„human leukocyte antigen“)- und moglicherweise atiopathogenetischem Hintergrund dar. Klinisch imponieren entzundungsbedingte Allgemeinsymptome und Ischamiezeichen, einhergehend mit erhohten serologischen Entzundungsmarkern.

ObjectiveTo develop and validate classification criteria for microscopic polyangiitis (MPA).MethodsPatients with vasculitis or comparator diseases were recruited into an international cohort. The study proceeded in five phases: (1) identification of candidate items using consensus methodology, (2) prospective collection of candidate items present at the time of diagnosis, (3) data-driven reduction of the number of candidate items, (4) expert panel review of cases to define the reference diagnosis and (5) derivation of a points-based risk score for disease classification in a development set using least absolute shrinkage and selection operator logistic regression, with subsequent validation of performance characteristics in an independent set of cases and comparators.ResultsThe development set for MPA consisted of 149 cases of MPA and 408 comparators. The validation set consisted of an additional 142 cases of MPA and 414 comparators. From 91 candidate items, regression analysis identified 10 items for MPA, 6 of which were retained. The final criteria and their weights were as follows: perinuclear antineutrophil cytoplasmic antibody (ANCA) or anti-myeloperoxidase-ANCA positivity (+6), pauci-immune glomerulonephritis (+3), lung fibrosis or interstitial lung disease (+3), sino-nasal symptoms or signs (−3), cytoplasmic ANCA or anti-proteinase 3 ANCA positivity (−1) and eosinophil count ≥1×109/L (−4). After excluding mimics of vasculitis, a patient with a diagnosis of small- or medium-vessel vasculitis could be classified as having MPA with a cumulative score of ≥5 points. When these criteria were tested in the validation data set, the sensitivity was 91% (95% CI 85% to 95%) and the specificity was 94% (95% CI 92% to 96%).ConclusionThe 2022 American College of Rheumatology/European Alliance of Associations for Rheumatology classification criteria for MPA are now validated for use in clinical research.

Approximately 5% of the world-wide population is affected by autoimmune diseases. Overall, autoimmune diseases are still difficult to treat, impose a high burden on patients, and have a significant economic impact. Like other complex diseases, e.g., cancer, autoimmune diseases develop over several years. Decisive steps in the development of autoimmune diseases are (i) the development of autoantigen-specific lymphocytes and (often) autoantibodies and (ii) potentially clinical disease manifestation at a later stage. However, not all healthy individuals with autoantibodies develop disease manifestations. Identifying autoantibody-positive healthy individuals and monitoring and inhibiting their switch to inflammatory autoimmune disease conditions are currently in their infancy. The switch from harmless to inflammatory autoantigen-specific T and B-cell and autoantibody responses seems to be the hallmark for the decisive factor in inflammatory autoimmune disease conditions. Accordingly, biomarkers allowing us to predict this progression would have a significant impact. Several factors, such as genetics and the environment, especially diet, smoking, exposure to pollutants, infections, stress, and shift work, might influence the progression from harmless to inflammatory autoimmune conditions. To inspire research directed at defining and ultimately targeting autoimmune predisease, here, we review published evidence underlying the progression from health to autoimmune predisease and ultimately to clinically manifest inflammatory autoimmune disease, addressing the following 3 questions: (i) what is the current status, (ii) what is missing, (iii) and what are the future perspectives for defining and modulating autoimmune predisease.

Small vessel vasculitis is characterized by a necrotizing inflammation of the vessel wall predominantly with involvement of small intraparenchymal arteries, arterioles, capillaries and venules. Medium-sized and occasionally large vessels can also be involved. Antineutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (granulomatosis with polyangiitis, microscopic polyangiitis, eosinophilic granulomatosis with polyangiitis) are differentiated from immune complex vasculitides based on immunopathological and serological aspects. Immune complex vasculitides include IgA vasculitis, cryoglobulinemic vasculitis, hypocomplementemic urticarial vasculitis (anti-C1q vasculitis) and anti-glomerular basement membrane disease. Epidemiological and next-generation sequencing-based studies have significantly contributed to the identification of predisposing environmental factors and genetic risk factors in recent years. Under specific conditions ANCA and immune complexes can induce premature intravascular activation of neutrophilic granulocytes with degranulation and release of enzymes and reactive oxygen species, which leads to vascular damage. In granulomatosis with polyangiitis and eosinophilic granulomatosis with polyangiitis various factors, such as barrier dysfunction and dysbiosis of the microbiome contribute to extravascular granuloma formation predominantly affecting the respiratory tract.Die Kleingefäßvaskulitis ist durch eine nekrotisierende Entzündung der Gefäßwand mit prädominantem Befall von kleinen intraparenchymatösen Arterien, Arteriolen, Kapillaren und Venolen charakterisiert. Mittelgroße und gelegentlich auch große Gefäße können mitbeteiligt sein. Hierbei wird unter immunpathologischen und serologischen Gesichtspunkten die antineutrophile zytoplasmatische Autoantikörper(ANCA)-assoziierte Vaskulitis (Granulomatose mit Polyangiitis, mikroskopische Polyangiitis, eosinophile Granulomatose mit Polyangiitis) von den Immunkomplexvaskulitiden unterschieden. Zu den Immunkomplexvaskulitiden zählen die Ig(Immunglobulin)A Vaskulitis, kryoglobulinämische Vaskulitis, hypokomplementämische Urtikariavaskulitis (Anti-C1q Vaskulitis) und die Anti-glomeruläre Basalmembranerkrankung. Epidemiologische und Hochdurchsatz-sequenzierungsbasierte Studien haben in den letzten Jahren wesentlich zur Identifizierung von prädisponierenden Umweltfaktoren und genetischen Risikofaktoren beigetragen. ANCA und Immunkomplexe können unter spezifischen Bedingungen eine vorzeitige intravasale endothelnahe Aktivierung von neutrophilen Granulozyten mit Degranulierung und Freisetzung von Enzymen und reaktiven Sauerstoffspezies induzieren, die zur Gefäßschädigung führt. Bei der Granulomatose mit Polyangiitis und eosinophilen Granulomatose mit Polyangiitis tragen verschiedene Faktoren wie beispielsweise eine Barrierestörung und Dysbiose des Mikrobioms zur hauptsächlich den Respirationstrakt betreffenden extravaskulären Granulombildung bei.

ZusammenfassungDie Granulomatose mit Polyangiitis (GPA) und die mikroskopische Polyangiitis (MPA) stellen als primäre nekrotisierende Kleingefäßvaskulitiden die häufigsten ANCA-assoziierten Vaskulitiden dar. Bei diesen, früher oft tödlich verlaufenden Erkrankungen kann heute durch eine Stadien-adaptierte Immunsuppression in den meisten Fällen eine Remission erzielt werden. Diese mündet jedoch nicht in eine Heilung oder medikamentenfreie Langzeitremission. Es bedarf deshalb einer remissionserhaltenden Therapie. Aktuelle randomisierte kontrollierte Studien zeigen, dass unter einer remissionserhaltenden Behandlung mit halbjährlich verabreichtem anti-B-Zell-Antikörper Rituximab weniger Rezidive auftreten als unter der bisherigen Standardmedikation mit Azathioprin bei vergleichbarem Nebenwirkungsprofil. Diese Daten führten 2018 zur Zulassung von Rituximab als remissionserhaltende Therapie der GPA und MPA. Unter einer solchen Rituximab-Therapie muss mit einer Immunglobulindepletion sowie späten Zytopenien mit begleitenden Infekten gerechnet werden. Leitlinien und Expertenempfehlungen zu Infektprophylaxen, Impfungen und Immunglobulinsubstitution werden in diesem Beitrag vorgestellt.

To prevent serious complications such as permanent loss of vision and structural vascular damage, treatment must be initiated quickly in patients with giant-cell arteritis (GCA). So far, usually long-term corticosteroids in cumulative high dosages have been the standard therapy option. However, steroids are often insufficient to achieve adequate disease control and are associated with serious adverse events. Therefore, steroid-sparing therapy options are the focus of interest.

ANCA-associated vasculitis (AAV) comprises granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA). While systemic vasculitis is a hallmark of all AAV, GPA is characterized by extravascular granulomatous inflammation, preferentially affecting the respiratory tract. The mechanisms underlying the emergence of neutrophilic microabscesses; the appearance of multinucleated giant cells; and subsequent granuloma formation, finally leading to scarred or destroyed tissue in GPA, are still incompletely understood. This review summarizes findings describing the presence and function of molecules and cells contributing to granulomatous inflammation in the respiratory tract and to renal inflammation observed in GPA. In addition, factors affecting or promoting the development of granulomatous inflammation such as microbial infections, the nasal microbiome, and the release of damage-associated molecular patterns (DAMP) are discussed. Further, on the basis of numerous results, we argue that, in situ, various ways of exposure linked with a high number of infiltrating proteinase 3 (PR3)- and myeloperoxidase (MPO)-expressing leukocytes lower the threshold for the presentation of an altered PR3 and possibly also of MPO, provoking the local development of ANCA autoimmune responses, aided by the formation of ectopic lymphoid structures. Although extravascular granulomatous inflammation is unique to GPA, similar molecular and cellular patterns can be found in both the respiratory tract and kidney tissue of GPA and MPA patients; for example, the antimicrobial peptide LL37, CD163+ macrophages, or regulatory T cells. Therefore, we postulate that granulomatous inflammation in GPA or PR3-AAV is intertwined with autoimmune and destructive mechanisms also seen at other sites.

Background and Aims Glucocorticoids (GC) and/or immunosuppressive agents are the mainstay of therapy for adult-onset IgA Vasculitis (IgAV), but their efficacy is often partial while their toxicity is relevant. Recently, rituximab (RTX) has been reported as a safe and effective option but only few data on renal outcome are available.1 RTX has also been used in a few cases of crescentic IgA Nephropathy (cIgAN), an IgAN subset with vasculitic lesions and poor response to conventional immunosuppressive regimens.2 We present the results of a multicentre cohort of patients with IgAV and cIgAN treated with RTX. Method The databases of 16 consorted European centres were investigated to screen for patients with adult-onset, biopsy-proven IgAV and cIgAN (crescents in ≥25% glomeruli and rapid eGFR worsening at presentation), who received RTX as induction therapy. We selected patients with active renal manifestations at the time of RTX. Remission was defined as a Birmingham Vasculitis Activity Score (BVAS)=0 or Results We identified 38 patients with IgAV and 12 patients with cIgAN who received RTX and had active renal involvement at the time of treatment. The median age at onset was 40 years (interquartile range, IQR, 25-53) and more than two-thirds of patients were male (Table 1). The median follow-up after RTX was 41 months (IQR 18-60). Renal outcomes are reported in Table 2. At the time of treatment, 24 patients (48%) had eGFR ≥60 mL/min/1.73 m2. All had IgAV and their median BVAS was 17 (IQR 10-22). Furthermore, all had microhaematuria and proteinuria. Renal histology showed mesangial or focal endocapillary proliferation in 12/17 (71%) patients who underwent biopsy (class II-IIIA according to Pillebout3). Twenty patients (83%) achieved remission; after a median of 12 months (range 9-14), four experienced a minor relapse and one had a major relapse with significant renal disease progression. Renal function remained stable in all but two patients who developed end-stage renal disease (ESRD). Micro-haematuria subsided in 14/24 (58%) and median 24h proteinuria decreased from 1750 mg (IQR 865-3275) to 175 mg (IQR 100-800) at last follow-up (p=0.029). Of the 26 patients with eGFR Remission rate and ESRD-free survival were respectively 86% and 92% in patients with IgAV, while they were respectively 42% and 42% in cIgAN patients. Furthermore, 21/24 (87%) patients who received RTX alone or combined to glucocorticoids but not to immunosuppressive agents achieved remission and 22/24 (92%) were ESRD-free at last follow-up. Of the 26 patients receiving immunosuppressive agents, 17 (65%) obtained remission and 18 (69%) were ESRD-free at last assessment. Over the whole follow-up, only one patient reported a severe adverse effect related to RTX (pneumonia). Conclusion Renal involvement in adult-onset IgAV and cIgAN is frequently severe. RTX, combined or not with other immunosuppressive agents, may improve renal manifestations and is well tolerated. IgAV patients show higher remission rates and a longer ESRD-free survival as compared to cIgAN patients.

Regulatory T cells (Treg) are crucial for the maintenance of peripheral tolerance and for the control of ongoing inflammation and autoimmunity. The cytokine interleukin-2 (IL-2) is essentially required for the growth and survival of Treg in the peripheral lymphatic tissues and thus plays a vital role in the biology of Treg. Most autoimmune and rheumatic diseases exhibit disturbances in Treg biology either at a numerical or functional level resulting in an imbalance between protective and pathogenic immune cells. In addition, in some autoimmune diseases, a relative deficiency of IL-2 develops during disease pathogenesis leading to a disturbance of Treg homeostasis, which further amplifies the vicious cycle of tolerance breach and chronic inflammation. Low-dose IL-2 therapy aims either to compensate for this IL-2 deficiency to restore a physiological state or to strengthen the Treg population in order to be more effective in counter-regulating inflammation while avoiding global immunosuppression. Here we highlight key findings and summarize recent advances in the clinical translation of low-dose IL-2 therapy for the treatment of autoimmune and rheumatic diseases.

Background Vasculitides comprise a group of rare diseases which affect less than 5 in 10.000 individuals. Most types of vasculitis can become organ- and life-threatening and are characterized by chronicity, high morbidity and relapses, altogether resulting in significant morbidity and mortality. Previous studies have been either monocentric or mainly retrospective – studies with a prospective design mostly consisted of rather small cohorts of 100 to 200 patients. The aim of the Joint Vasculitis Registry in German-speaking countries (GeVas) is to record all patients who have been recently diagnosed with vasculitis or who have changed their treatment due to a relapse (inception cohort). In GeVas, data are collected prospectively in a multicenter design in Germany, Austria and Switzerland. By this approach, courses of vasculitis and their outcomes can be monitored over an extended period. Methods GeVas is a prospective, web-based, multicenter, clinician-driven registry for the documentation of organ manifestations, damage, long-term progress and other outcomes of various types of vasculitis. The registry started recruiting in June 2019. As of October 2020, 14 centers have been initiated and started recruiting patients in Germany. Involvement of sites in Austria and the German-speaking counties of Switzerland is scheduled in the near future. Discussion In June 2019, we successfully established a prospective multicenter vasculitis registry being the first of its kind in German-speaking countries. The participating centers are currently recruiting, and systematic analysis of long-term vasculitis outcomes is expected in the ensuing period. Trial registration German Clinical Trials Register (Deutsches Register Klinischer Studien): DRKS00011866. Registered 10 May 2019.

Einleitung: Die Riesenzellarteriitis (RZA) und Takayasu – Arteriitis (TAK) sind Großgefäßvaskulitiden (GGV), die zu schweren Komplikationen wie Erblindung, Organ- und Extremitätenischämien und bei einem Teil der Erkrankten zum Tod führen können. Glukokortikoid-assoziierte[zum vollständigen Text gelangen Sie über die oben angegebene URL], Deutscher Rheumatologiekongress 2020, 48. Kongress der Deutschen Gesellschaft für Rheumatologie (DGRh), 34. Jahrestagung der Deutschen Gesellschaft für Orthopädische Rheumatologie (DGORh)

The nomenclature system agreed upon by the Chapel Hill Consensus Conference (CHCC) with respect to the terminology and precise definition of the various types of vasculitis has gained widespread interdisciplinary and international acceptance. As the revised version from 2012 (CHCC 2012) does not address the special features of vasculitis of the skin, it has recently been supplemented with an addendum containing the nomenclature of cutaneous vasculitides (D-CHCC). The present article provides the German translation of the terms and defintions of the D-CHCC as well as additional explanatory comments. The goal is to enable German-speaking health care providers to more readily apply these defined terms - which are based on interdisciplinary consensus - in everyday clinical practice and to facilitate assessment of their practicability and relevance in patient care. If the majority of cutaneous vasculitides diagnosed can be matched with any of the defined entities presented herein, it might subsequently be possible to develop a classification system and diagnostic algorithms.

Circulating anti-neutrophilic cytoplasmic autoantibodies targeting proteinase 3 (PR3-ANCA) are a diagnostic and pathogenic hallmark of granulomatosis with polyangiitis (GPA). It is, however, incompletely understood if inflamed tissue supports presence or emergence of PR3-ANCA+ B cells. In search of such cells in inflamed tissue of GPA, immunofluorescence staining for IgG and a common PR3-ANCA idiotype (5/7 Id) was undertaken. Few 5/7 Id+/IgG+ B cells were detected in respiratory and kidney tissue of GPA. To gain more insight into surrogate markers possibly indicative of an anti-PR3-response, a meta-analysis comprising IGVH and IGVL genes derived from respiratory tract tissue of GPA (231 clones) was performed. Next generation sequencing-based IGHV genes derived from peripheral blood of healthy donors (244.353 clones) and previously published IGLV genes (148 clones) served as controls. Additionally, Ig genes of three murine and five known human monoclonal anti-PR3 antibodies were analyzed. Primary and probably secondary rearrangements led to altered VDJ usage and an extended complementarity determining region 3 (CDR3) of IGHV clones from GPA tissue. Selection against amino acid exchanges was prominent in the framework region of IGHV clones from GPA tissue. The comparison of V(D)J rearrangements and deduced amino acid sequences of the CDR3 yielded no identities and few similarities between clones derived from respiratory tissue of GPA and anti-PR3 antibodies, arguing against a presence of B cells that carry PR3-ANCA-prone Ig genes among the clones. In line with the scarcity of 5/7 Id+ B lymphocytes in GPA tissue, the results suggest that with respect to a local anti-PR3 response, methods detecting rare clones are required.