antineutrophil cytoplasmic antibody

:  any of a group of autoantibodies that bind to cytoplasmic regions of neutrophils and are associated with diseases (such as Wegener's granulomatosis, Churg-Strauss syndrome, and polyarteritis nodosa) characterized by inflammation of small blood vessels A positive test for antineutrophil cytoplasmic antibody may be associated with a vasculitis of the skin …—Barbara J. Rutledge, Skin and Allergy News, December 2007 … a test that seeks the antineutrophilic cytoplasmic antibody (ANCA), and is generally diagnostic of vasculitis, but not specific enough to be definitive.—Robert G. Lahita and Ina L. Yalof, Women and Autoimmune Disease: The Mysterious Ways Your Body Betrays Itself, 2004—abbreviation ANCA