DR Medhat MRCP

ANCA
o There are two main types of anti-neutrophil cytoplasmic antibodies (ANCA) :
1- Cytoplasmic (cANCA)
2- Perinuclear (pANCA
For the exam, remember:
•cANCA : Wegener's Granulomatosis
•pANCA : Churg-Strauss syndrome + others (see below)
cANCA:
o Most common target serine proteinase 3 (PR3)
o Some correlation between cANCA levels and disease activity
o Wegener's granulomatosis, positive in > 90%
o Microscopic polyangiitis, positive in 40%
pANCA:
o Most common target is myeloperoxidase (MPO)
o Cannot use level of pANCA to monitor disease activity
o Associated with
1. Immune crescentic glomerulonephritis (positive in c. 80% of patients)
2. Microscopic polyangiitis, positive in 50-75%
3. Churg-Strauss syndrome, positive in 60%
4. Wegener's granulomatosis, positive in 25%
Other causes of positive ANCA (usually pANCA)
5. Inflammatory bowel disease (Ulcerative colitis > Crohn's)
6. Connective tissue disorders: RA, SLE, Sjogren's
7. Autoimmune hepatitis.
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