Novel clinical and diagnostic aspects of antineutrophil cytoplasmic antibodies.

Johannes Schulte-Pelkum,Makoto Miyara,Antonella Radice,Lucile Musset,Marcos Lόpez Hoyos,Carol Buchner,Laura Stinton,Gabriella Lakos,Gary L Norman,Michael Mahler

doi:10.1155/2014/185416

Abstract

Antineutrophil cytoplasmic antibodies (ANCA) are the serological hallmark of some idiopathic systemic vasculitides. Besides the investigation of ANCA-associated vasculitis (AAV) and constant effort for a standardized nomenclature and classification of the AAV, a main focus of research during the last few years has been to constantly improve the performance of enzyme immunoassays. With the latest so called third generation ELISA, this goal seemed to be fulfilled. The International Consensus Statement on Testing and Reporting of ANCA gave recommendations for standardized strategies for the serological diagnosis of ANCA. New developments now target the system immanent drawbacks of the respective diagnostic methods, be it the need for batching and the long time to result for ELISA, or the high likelihood of error and subjectivity of indirect immunofluorescence (IIF). Random access technology and multiplexing for solid phase assays as well as digital imaging for IIF are tools which may help to expedite and simplify routine diagnostics in the lab and in emergency settings. Recent findings indicate that PR3-ANCA have clinical utility beyond the diagnosis of AAV. PR3-ANCA can also serve as an aid for the differentiation between ulcerative colitis (UC) and Crohn's disease (CrD) and the stratification of UC patients. This review provides a detailed review of what is known about ANCA and highlights the latest research and state-of-the-art developments in this area.

Highlights

In 1985 van der Woude et al reported the strong association of Antineutrophil cytoplasmic antibodies (ANCA) producing a diffuse granular cytoplasmic staining pattern on ethanol-fixed neutrophils (C-ANCA) and granulomatosis with polyangiitis (GPA) (formerly known as Wegener’s granulomatosis (WG)) [3, 4]; a few years later, ANCA producing a perinuclear fluorescent pattern (P-ANCA) on the same cellular substrate were described in patients with idiopathic necrotizing crescentic glomerulonephritis and microscopic polyangiitis (MPA) [5]
ANCA are the serological hallmark of some idiopathic systemic vasculitides, and the term ANCA-associated vasculitis (AAV) has been used to collectively name those primary small vessel vasculitic syndromes in which circulating ANCA are commonly found: MPA and its renal limited form, GPA, and eosinophilic granulomatosis with polyangiitis (EGPA) [formerly known as Churg-Strauss syndrome (CSS)] [14, 15]
The names of the common forms of vasculitis have been recently revised so that the eponyms such as WG and CSS have been changed to GPA and EGPA, respectively

Summary

Introduction

ANCA are the serological hallmark of some idiopathic systemic vasculitides, and the term ANCA-associated vasculitis (AAV) has been used to collectively name those primary small vessel vasculitic syndromes in which circulating ANCA are commonly found: MPA and its renal limited form (pauci-immune necrotizing glomerulonephritis), GPA, and eosinophilic granulomatosis with polyangiitis (EGPA) [formerly known as Churg-Strauss syndrome (CSS)] [14, 15] This approach, adopted by the International Chapel Hill Consensus Conference (CHCC) and by the European Vasculitis Study Group (EUVAS), is supported by the striking clinical and histological similarities between the AAV, the widespread use of ANCA as a diagnostic marker, and the growing evidence of their pathogenetic potential [16].

Diagnostic Methods for ANCA Detection

ANCA as Biomarkers in Inflammatory Bowel Disease

Conclusion

Findings

Conflict of Interests