What is an antineutrophil cytoplasmic antibodies (ANCA) test?This test looks for antineutrophil cytoplasmic antibodies (ANCA) in your blood. Antibodies are proteins that your immune system makes to fight foreign substances like viruses and bacteria. But ANCAs attack healthy cells known as neutrophils (a type of white blood cell) by mistake. This can lead to a disorder known as autoimmune vasculitis. Autoimmune vasculitis causes inflammation and swelling of the blood vessels.Blood vessels carry blood from your heart to your organs, tissues, and other systems, and then back again. Types of blood vessels include arteries, veins, and capillaries. Inflammation in the blood vessels can cause serious health problems. Problems vary depending on which blood vessels and body systems are affected.There are two main kinds of ANCA. Each targets a specific protein inside white blood cells:pANCA, which targets a protein called MPO (myeloperoxidase)cANCA, which targets a protein called PR3 (proteinase 3)The test can show whether you have one or both types of antibodies. This can help your health care provider diagnose and treat your disorder.Other names: ANCA antibodies, cANCA pANCA, cytoplasmic neutrophil antibodies, serum, anticytoplasmic autoantibodies
