Antibodies to components of neutrophil cytoplasm: a new diagnostic tool in patients with Wegener's granulomatosis and systemic vasculitis.

Eleven patients with symptoms highly suggestive of Wegener's granulomatosis are described. In spite of extensive investigation, only in two patients was a firm histological diagnosis of Wegener's granulomatosis obtained, while the remaining patients were either diagnosed as having unclassifiable systemic vasculitis or had no histological diagnosis made. This sometimes resulted in diagnostic and therapeutic delay and irreversible organ damage. Antibodies to components of neutrophil cytoplasm--recently demonstrated to be specific for Wegener's granulomatosis--were detected by indirect immunofluorescence in 10 of 11 patients, and it appears likely that antibodies to components of neutrophil cytoplasm will prove to be of great value in early diagnosis.