Anti-Neutrophil Cytoplasmic Antibody (ANCA)

History

Anti-Neutrophil Cytoplasmic Antibodies (ANCA): antibodies directed against neutrophil microbiocidal components, which are used in host defense
ANCA antibodies activate neutrophils, monocytes, and endothelial cells
Role of Infection in ANCA Development
- ANCA has been found to be directed against various viral/bacterial/fungal/protozoal antgens, as well as endocarditis and cystic fibrosis
- Chronic or recurent infection can result in exacerbation of pumonary vasculitis or relapse
- Hypothesis: infections may give rise to ANCA through molecular mimicry

c-ANCA (cytoplasmic staining): typically directed against proteinase 3 (PR3)
- Sensitivity: approximately 90-95% for systemic Wegener’s Granulomatosis, but only 65-85% in organ-limited Wegener’s Granulomatosis
p-ANCA (perinuclear staining): typically directed against myeloperoxidase (MPO)
- Sensitivity/Specificity: generally considered poor sensitivity and specificity (as they can be found in multiple diseases)
x-ANCA: typically found in inflammatory bowel disease

Wegener’s Granulomatosis (see [[Wegeners Granulomatosis]]): c-ANCA
Churg-Strauss Syndrome (see [[Churg-Strauss Syndrome]]): p-ANCA
Microscopic Polyangiitis (see [[Microscopic Polyangiitis]]): p-ANCA
Pauci-Immune Glomerulonephritis (see [[Pauci-Immune Glomerulonephritis]]): p-ANCA
Isolated Pulmonary Capillaritis (see [[Isolated Pulmonary Capillaritis]]): p-ANCA
Polyarteritis Nodosa (see [[Polyarteritis Nodosa]]): p-ANCA
Rheumatoid Arthritis (see [[Rheumatoid Arthritis]]):: p-ANCA
Goodpasture’s Syndrome (see [[Goodpastures Syndrome]]): p-ANCA
Drugs
- All-Trans Retinoic Acid (see [[All-Trans Retinoic Acid]])
- Phenytoin (see [[Phenytoin]])
- Propylthiouracil (see [[Propylthiouracil]])
- Mitomycin (see [[Mitomycin]])