Classification, diagnosis and treatment of ANCA-associated vasculitis

Biomarkers of fibrosis, kidney tissue injury and inflammation may predict severity and outcome of renal ANCA – associated vasculitis

Background

Activity and chronicity of kidney involvement in ANCA-associated vasculitis (AAV) can be currently reliably evaluated only by kidney biopsy. In this study, we measured a panel of serum and urinary biomarkers collected at the time of kidney biopsy and hypothesized that they could reflect specific histopathological parameters in the biopsy and help to predict prognosis.

Methods

We examined a cohort of 45 patients with AAV and 10 healthy controls. Biomarker levels (DKK-3, CD163, EGF, PRO-C6 and C3M) were measured in this study by ELISA. Biopsies were scored with a scoring system for AAV (focal x crescentic x sclerotic x mixed class) and interstitial fibrosis was quantified.

Results

Levels of urinary DKK-3, CD163, EGF, PRO-C6 and C3M significantly differed among biopsy classes in AAV, with urinary DKK-3 and PRO-C6 levels being highest in the sclerotic class and lowest in the focal class, urinary CD163 levels highest in the crescentic class and urinary C3M levels highest in the focal class. Moreover, the urinary biomarkers were able to discriminate focal biopsy class from the other classes. Urinary DKK-3, EGF, PRO-C6 and C3M levels measured at the time of biopsy were also significantly related to the extent of fibrosis and to the final kidney function at the end of follow-up.

Conclusions

This small pilot study suggests that selected urinary biomarkers of fibrosis and inflammation may reflect changes in the kidney biopsy and be prognostic of kidney outcome in patients with AAV.

Oral manifestations of anti-neutrophil cytoplasmic antibody-associated vasculitis: an update and narrative review of the literature

Anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) is a multisystem disorder of small blood vessels subdivided into granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA). Oral manifestations (OMs) have been reported to include mucosal ulceration, gingival enlargement, alveolar bone necrosis, tooth loss, oro-antral communication, palatal perforation, parotitis, and candidal infection mainly in GPA. They may appear during the course of the disease, as a disease flare-up, or as the presenting sign. These OMs are often nonspecific and can mimic an array of conditions, therefore formulating a differential diagnosis can be challenging. This review updates the OMs of GPA, and, for the first, time includes OMs of other AAVs. It provides recommendations for the overall assessment and the diagnosis and management of all AAV OMs with considerations for treatment coordination. The role of oral health care providers in multidisciplinary care is highlighted.

ANCA Associated Vasculitis (AAV): A Review for Internists

Anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitis (AAV) compromise a rare group of necrotizing small to medium vessel vasculitides that constitute three distinct disorders: granulomatosis with polyangiitis (GPA) (formerly known as Wegener's granulomatosis), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA) (formerly known as Churg-Strauss syndrome).AAV is characterized by the usual presence of circulating autoantibodies to the neutrophil proteins leukocyte proteinase 3 (PR3-ANCA) or myeloperoxidase (MPO-ANCA). These antibodies can activate neutrophils and the complement system resulting in vessel wall inflammation and damage.The clinical presentation of AAV varies from non-severe (non-life threatening) to severe often with potentially life-threatening multi-organ involvement. Early recognition and diagnosis are crucial. In the past two decades, advances in understanding the pathophysiology of AAV have led to development of new treatments and resulted in significant improvement in general outcomes and survival rates.This narrative review will focus on GPA and MPA. We will highlight clinical manifestations, diagnosis, disease monitoring, and treatment strategies in patients with AAV.

Polyangiitis overlap syndrome: a novel presentation of microscopic polyangiitis and eosinophilic granulomatosis with polyangiitis

Polyangiitis overlap syndrome (POS) is a diagnostic term coined by Leavitt and Fauci that characterises patients with overlapping features of more than one vasculitis. Prior case studies of antineutrophil cytoplasmic antibodies (ANCA)-associated POS have only been published in patients with eosinophilic granulomatosis with polyangiitis (EGPA) and granulomatosis with polyangiitis alongside proteinase-3/cytoplasmic (C)-ANCA positivity. We present a case of a 60-year-old woman with dyspnoea, hemoptysis, positive perinuclear-ANCA and renal biopsy demonstrating evidence of microscopic polyangiitis. In addition, our patient also had asthma, mononeuritis multiplex, eosinophilia and migratory pulmonary infiltrates, thus fulfilling the criteria for EGPA. This novel case report suggests that POS is not limited to C-ANCA positivity and has variable presentations.

End-stage renal disease in ANCA-associated vasculitis

The outcomes in patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis have improved significantly over the past decades, although a significant proportion of them still reach end-stage renal disease (ESRD). Renal replacement therapy (RRT) is associated with a relatively low risk of relapsing vasculitis as a result of anti-rejection treatment after kidney transplantation or quiescence of the autoimmune process in haemodialysis patients, but a flare of vasculitis in the latter setting presents a challenge because the treatment is poorly tolerated. There are benefits of rituximab in haemodialysed patients, as it is more steroid sparing in the treatment of extrarenal disease. More favourable outcomes of kidney transplantation compared with haemodialysis support its use as a preferable method of RRT in patients with vasculitis remission or low disease activity.