ACR, EULAR Classification Criteria for Granulomatosis With Polyangiitis (Part 5)
Before we start the topic for this week, it is prudent to get a refresher on the essential terms that will be appearing several times in this column so that we can be on the same page.
The antineutrophil cytoplasmic antibody (ANCA)–associated vasculitides (AAV) are multisystem disorders involving inflammation of the small blood vessels and include granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA).
GPA is characterized by necrotizing granulomatous inflammation involving the ears, nose, and upper and lower respiratory tracts, and necrotizing vasculitis affecting predominantly small-tomedium-sized vessels, often including necrotizing glomerulonephritis.
Now let’s start the discussions.
The Diagnostic and Classification Criteria in Vasculitis (DCVAS) is a key concept that we need to keep in mind for the purposes of this discussion.
In the crafting of classification items for the systemic vasculitides, the Steering Committee identified at least 1,000 candidate items for the DCVAS case report.
The DCVAS prospective observational study was done between January 2011 and December 2017 and the DCVAS study involved 6,991 participants from 136 sites in 32 countries.
Following a data-driven and expert consensus, 91 items from the DCVAS case report were retained including 45 clinical and 16 biopsy items. Some clinical items were discarded in favor of similar but specific descriptors.
Around 55 experts reviewed information derived from the case report forms for 2,871
cases submitted to the panel to derive a gold standard in the classification.
In the final analysis, a model of 26 independent items have been identified that are useful to the management of ANCA-AA V.
We will be having the conclusion of this discussion in our next column.