Antineutrophil cytoplasmic autoantibody-associated diseases: a pulmonologist's perspective

The development of the antineutrophil cytoplasmic autoantibody (ANCA) test has lent support to the concept of Wegener's granulomatosis as a spectrum that may affect one or more of the major anatomic sites: upper respiratory tract (E), lung (L), or kidney (K). It is C-ANCA that has high specificity for Wegener's granulomatosis (WG). The sensitivity is highest in the fully expressed Wegener's triad, or ELK, and less in local regional disease. It is possible that isolated manifestations such as episcleritis, subglottic stricture, or diffuse alveolar hemorrhage associated with C-ANCA may be considered in the Wegener's spectrum, although traditional histopathologic criteria are lacking. Until specific etiologic agents are uncovered for the various ANCA-associated entities, classification schemes should continue to employ previously established clinicopathologic syndromes such as WG using the ANCA test to better define their clinical spectrums.