ANCA (Anti-Neutrophil Cytoplasmic Antibodies)

ANCA, or Anti-Neutrophil Cytoplasmic Antibodies, are autoantibodies - proteins produced by the immune system that mistakenly target and attack the body's own neutrophils, a type of white blood cell involved in fighting infections. The presence of ANCA is associated with certain autoimmune diseases, notably vasculitis, where blood vessels become inflamed. These antibodies can help doctors diagnose these conditions and understand their activity, guiding treatment decisions. Essentially, ANCAs are markers of immune system misdirection, indicating that the body's defense mechanisms are attacking its own vascular structures.