ANCA-associated vasculitis--an autopsy study.

The purpose of the study was to analyse the autopsies of 31 patients (20 female, mean age 67 years, range 28-87 years; and 11 male, mean age 66 years, range 47-80 years) with antineutrophil cytoplasmic antibodies (ANCA)-positive vasculitis, which was clinically confirmed in 25 patients and suspected in 6 patients, who had been treated and had died between 1989 and 1999. Kidney biopsy was performed in 22 patients on average 33 months (range, 1-132 months) prior to death. Biopsy and autopsy tissue specimens were examined by standard light and immunofluorescence microscopy techniques. Pauci-immune extracapillary glomerulonephritis was found in nearly the same percentage of 22 renal biopsies and 31 autopsies, namely in 91% and 84%, respectively. Active necrotising extracapillary glomerulonephritis was the prevailing lesion in 75% of biopsies, while advanced sclerosing glomerular lesions prevailed in 69% of autopsies. In the biopsies, necrotising lesions predominated in patients with ANCA of proteinase 3 specificity, while sclerotic lesions were more often associated with myeloperoxidase-ANCA. In the autopsies, florid necrotising systemic vasculitis coexisted in 2 patients with advanced sclerosing glomerulonephritis. Autopsies revealed the actual expansion of vasculitic disease, disclosed clinically silent vasculitic involvement of unusual locations and, in 3 patients, confirmed the clinically suspected vasculitis. The final diagnoses in 31 patients were as follows: Wegener's granulomatosis (5 men, 2 women), microscopic polyangitis (10 women, 2 men), pauci-immune crescentic glomerulonephritis (4 women, 3 men), a single case each of polyarteritis nodosa and isolated cutaneous vasculitis. In 3 patients, suspected vasculitis was not confirmed at autopsy. Nineteen of 31 patients died from septic infections or necrotising pneumonias, and 6 patients from progressive or recurrent vasculitis with complications, altogether nearly 80%. Cardiovascular failure, including pulmonary thrombembolism, caused death in 6 patients.