Clinical evaluation of antineutrophil cytoplasmic autoantibodies in ANCA-associated diseases

Antineutrophil cytoplasmic autoantibodies have been performed in 110 patients referred to the laboratory as a presumptive systemic vasculitis, idiopathic crescentic glomerulonephritis, inflammatory bowel disease or SLE with vascular manifestation. 25 patients were found to be positive with c-, or p-ANCA patterns in indirect immunofluorescent test. We describe several cases in which histological confirmation is not available, an early consideration of a positive ANCA test may offer a reliable diagnosis and effective therapeutic handling, while the cases when the test was not considered, the occurence of relapse was inevitable.