Granulomatosis With Polyangiitis (Wegener Granulomatosis): Then and Now

Area of Science:

• Rheumatology
• Immunology
• Pathology

Background:

• The 1954 article by Godman and Churg defined Wegener's Granulomatosis, now granulomatosis with polyangiitis (GPA).
• This seminal work linked various small-vessel vasculitides, including allergic angiitis and granulomatosis (now eosinophilic granulomatosis with polyangiitis, EGPA) and microscopic polyangiitis.
• These conditions are now recognized as a spectrum of pauci-immune anti-neutrophil cytoplasmic antibody (ANCA)-associated small-vessel vasculitis.

Purpose of the Study:

• To provide historical context for the 1954 Godman and Churg article on Wegener's Granulomatosis.
• To review current understanding and classification of GPA and related small-vessel vasculitides.
• To discuss the role of ANCA specificity in defining these conditions.

Main Methods:

• Review of published literature.
• Historical analysis of the definition and classification of small-vessel vasculitis.
• Examination of current diagnostic criteria and proposed future classifications.

Main Results:

• GPA is characterized by granulomatous inflammation and necrotizing vasculitis, typically affecting the upper respiratory tract, lungs, and kidneys.
• ANCAs, specifically anti-proteinase 3 (PR3) and anti-myeloperoxidase (MPO), are key diagnostic markers.
• PR3-ANCAs are typically associated with GPA, while MPO-ANCAs are linked to microscopic polyangiitis and EGPA.

Conclusions:

• GPA can affect any organ, with characteristic upper respiratory tract involvement and lung manifestations including necrotizing nodules or capillaritis with hemorrhage.
• The classification of these vasculitides may evolve to be primarily based on ANCA specificity (PR3 or MPO).
• ANCA type appears to correlate with the pattern of organ involvement, suggesting a unifying classification principle.