The American College of Rheumatology 1990 criteria for the classification of wegener's granulomatosis

TLDR

WG classification is crucial because it distinguishes patients who need cyclophosphamide from those who can be treated with corticosteroids alone. The study aimed to develop criteria that reliably differentiate Wegener’s granulomatosis from other vasculitides with high sensitivity and specificity. The authors derived the criteria by comparing 85 WG patients to 722 vasculitis controls, selecting four key features—abnormal urinary sediment, abnormal chest radiograph, oral ulcers or nasal discharge, and granulomatous biopsy inflammation—for a traditional format and adding hemoptysis in a five‑criterion classification tree. Two or more of the four traditional criteria yield 88.2 % sensitivity and 92.0 % specificity, whereas the five‑criterion tree achieves 87.1 % sensitivity and 93.6 % specificity.

Abstract

Abstract Criteria for the classification of Wegener's granulomatosis (WG) were developed by comparing 85 patients who had this disease with 722 control patients with other forms of vasculitis. For the traditional format classification , 4 criteria were selected: abnormal urinary sediment (red cell casts or >5 red blood cells per high power field), abnormal findings on chest radiograph (nodules, cavities, or fixed infiltrates), oral ulcers or nasal discharge, and granulomatous inflammation on biopsy. The presence of 2 or more of these 4 criteria was associated with a sensitivity of 88.2% and a specificity of 92.0%. A classification tree was also constructed with 5 criteria being selected. These criteria were the same as for the traditional format, but included hemoptysis. The classification tree was associated with a sensitivity of 87.1% and a specificity of 93.6%. We describe criteria which distinguish patients with WG from patients with other forms of vasculitis with a high level of sensitivity and specificity. This distinction is important because WG requires cyclophosphamide therapy, whereas many other forms of vasculitis can be treated with corticosteroids alone.