- At least two of the five modified American College of Rheumatology (ACR) criteria for a diagnosis of WG. The modified ACR criteria are: (1) nasal or oral inflammation, defined as the development of painful or painless oral ulcers or purulent or bloody nasal discharge; (2) abnormal chest radiograph, defined as the presence of nodules, fixed infiltrates, or cavities; (3) active urinary sediment, defined as microscopic hematuria (> 5 red blood cells per high-power field) or red blood cell casts; (4) granulomatous inflammation on biopsy, defined as histologic changes showing granulomatous inflammation within the wall of an artery or in the perivascular or extravascular area (artery or arteriole); and (5) positive serum ELISA for ANCAs (anti-neutrophil cytoplasmic antibodies) directed at PR-3.