Granulomatous Inflammation in ANCA-Associated Vasculitis

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

[Hughes-Stovin syndrome: a life-threatening manifestation of Behçet's syndrome].

Hughes-Stovin syndrome (HSS) is a systemic inflammatory condition of unknown origin that is considered to be part of the Behçet's syndrome (BS) spectrum. Recurrent venous thrombosis and superficial thrombophlebitis in combination with bilateral pulmonary artery aneurysms (PAA) represent the hallmark of HSS. The diagnostic evaluation includes computed tomography pulmonary angiography to detect signs of pulmonary vasculitis. The management of HSS is based on the European Alliance of Associations for Rheumatology (EULAR) recommendations for BS and mainly comprises immunosuppressive therapy with glucocorticoids and cyclophosphamide. In addition to drug therapy, PAA should be evaluated for interventional treatment. Spontaneous PAA rupture due to fragile vessel architecture can occur even in cases of remission and/or PAA regression

[Cocaine-induced vasculitis and mimics of vasculitis].

Cocaine is a psychotropic tropane alkaloid and stimulant drug. Nasal insufflation of cocaine powder is a common route of administration. In Germany, cocaine is frequently adulterated with levamisole, an anthelminthic drug with immunomodulatory effects. Both substances are linked to various autoimmune conditions. Cocaine-induced midline destructive lesions cause a progressive destruction of osteocartilaginous structures within the upper respiratory tract and can mimic localized granulomatosis with polyangiitis. In addition, systemic vasculitis due to cocaine and levamisole has been reported. Differentiation of these conditions from primary vasculitis can be challenging because antineutrophil cytoplasmic antibodies (ANCA) are commonly detected. Early diagnosis of these conditions is crucial as clinical improvement is closely related to drug cessation

Plasma cells within granulomatous inflammation display signs pointing to autoreactivity and destruction in granulomatosis with polyangiitis

International audienceIntroductionPlasma cells residing in inflamed tissues produce antibodies in chronic inflammatory and systemic autoimmune diseases. This study examined if plasma cells, located within inflamed nasal tissue in granulomatosis with polyangiitis (GPA), express features potentially associated with the autoimmune and destructive character of this disease.MethodsIg gene mutation patterns of individual tissue-derived plasma cells from GPA (n = 5) were analyzed, by using laser-assisted microdissection followed by semi-nested polymerase chain reaction (PCR). Signs of B-lymphocyte maturation (ectopic lymphoid structures, ELS) and survival (a proliferation-inducing ligand, APRIL; B-cell maturation antigen, BCMA; transmembrane-activator and calcium modulator and cyclophilin interactor, TACI; receptor activator of nuclear factor κB ligand, RANKL) were examined in nasal tissues or serum, respectively, by using immunohistochemistry/fluorescence and enzyme-linked immunosorbent assay, ELISA.ResultsPlasma-cell derived Ig genes (light- and heavy-chain pairs, n = 4; heavy chains, n = 33) resembled mutation patterns seen in other autoimmune diseases, predominantly displaying selection against replacement mutations within the framework region of Ig genes (10 of 15), which is responsible for structural integrity. Ectopic lymphoid structures were similar between GPA and a disease control (that is, unspecific chronic rhinosinusitis. However, histomorphologic features distinguishing GPA from rhinosinusitis (that is, neutrophilic microabscess and granuloma) expressed considerable amounts of membrane-associated and secreted APRIL, respectively. The latter was co-localized with CD138 and found in close proximity to cells expressing IgG, TACI, and BCMA. Interestingly, plasma cells strongly expressed receptor activator of nuclear factor κB ligand (RANKL), apart from fibroblast-like cells.ConclusionsPlasma cells within granulomatous inflammation appear to display features that might be required for autoreactivity and, possibly, RANKL-mediated destruction in GPA

Successful reconstruction of an ocular defect resulting from granulomatosis with polyangiitis, following treatment with rituximab

Purpose: To report a unique case of orbital inflammatory disease which was ultimately diagnosed as granulomatosis with polyangitis (GPA) and thus successfully treated. Observation: A 47 year-old man presented with a rapidly progressive necrotic soft tissue mass within the medial antero-superior aspect of the right eyelid and orbit. He also had transient retinal vasculitis in the left. Serology, histology and imaging were atypical of, but consistent with, GPA. He was thus successfully treated with intravenous rituximab followed by reconstruction of the medial eyelid. Conclusion and importance: A high index of suspicion of GPA is required in orbital inflammatory disease, especially when typical diagnostic findings are absent. Keywords: Orbital inflammatory disease, Rituximab, Eyelid reconstruction, Granulomatosis with polyangiiti

Cartilage destruction in granulomatosis with polyangiitis (Wegener's granulomatosis) is mediated by human fibroblasts after transplantation into immunodeficient mice

A key feature of granulomatosis with polyangiitis (GPA; or Wegener's granulomatosis) is the granulomatous inflammation of the upper respiratory tract, which leads to the subsequent destruction of adjacent tissues. The aim of our work was to study the histopathological and cellular components of tissue destruction of human GPA tissue transplanted into immunodeficient mice. Biopsy specimens from patients with active GPA (n = 10) or sinusitis (controls, n = 6) were s.c. co-implanted with healthy allogeneic human nasal cartilage into immunodeficient pfp/rag2(-/-) mice. Transplants were examined for their destructive capability of the allografted human cartilage. In addition, nasal fibroblasts from patients with GPA (n = 8) and control healthy nasal fibroblasts (n = 5) were cultured, and cell proliferation and apoptosis were quantified. mRNA and protein levels of matrix metalloproteinases and cytokines were evaluated at baseline and after proinflammatory stimulation. GPA implants showed massive destruction of the co-implanted human cartilage, whereas cartilage destruction was only marginal in control samples. Destruction was mediated by human fibroblasts and could be inhibited by corticoid treatment. The up-regulated production of matrix metalloproteinases 1, 3, and 13 and cytokines IL-6 and IL-8 was found in vivo and in vitro. Although proliferation of isolated fibroblasts was comparable between GPA and controls, GPA samples showed a significant delay of apoptosis. The destruction of nasal cartilage in GPA is mainly mediated by fibroblasts that can be blocked by corticosteroids, and this tissue destruction is not dependent on the influx of leukocytes

The Joint Vasculitis Registry in German-speaking countries (GeVas) - a prospective, multicenter registry for the follow-up of long-term outcomes in vasculitis.

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