Anti-neutrophil cytoplasmic antibodies (ANCA) are important as they are associated with a number of small-vessel vasculitides, including:

Clinical features

ANCA associated vasculitis is more common with increasing age. Whilst each condition has its own distinct features, there are a number of common findings:
  • renal impairment
    • caused by immune complex glomerulonephritis → raised creatinine, haematuria and proteinuria
  • respiratory symptoms
    • dyspnoea
    • haemoptysiis
  • systemic symptoms
    • fatigue
    • weight loss
    • fever
  • vasculitic rash: present only in a minority of patients
  • ear, nose and throat symptoms
    • sinusitis


General approach to first-line investigations:
  • urinalysis for haematuria and proteinuria
  • bloods:
    • urea and creatinine for renal impairment
    • full blood count: normocytic anaemia and thrombocytosis may be seen
    • CRP: raised
    • ANCA testing (see below)
  • chest x-ray: nodular, fibrotic or infiltrative lesions may be seen

ANCA types

There are two main types of ANCA - cytoplasmic (cANCA) and perinuclear (pANCA). There is considerable overlap between which antibodies are found in which condition, but as a rule of thumb:

TargetSerine proteinase 3 (PR3)myeloperoxidase (MPO)
Granulomatosis with polyangiitis90%25%
Eosinophilic granulomatosis with polyangiitis Low50%
Microscopic polyangiitis 40%75%
Other associated conditionsUlcerative colitis (70%)
Primary sclerosing cholangitis (70%)
Anti-GBM disease (25%)
Crohn's disease (20%)
Use for monitoringSome correlation between cANCA levels and disease activityCannot use level of pANCA to monitor disease activity


Once suspected, ANCA associated vasculitis should be managed by specialist teams (e.g. renal, rheumatology, respiratory) to allow an exact diagnosis to be made. Kidney or lung biopsies may be taken to aid the diagnosis.

The mainstay of management is immunosuppressive therapy.


Eosinophilic granulomatosis with polyangiitis
Granulomatosis with polyangiitis
Microscopic polyangiitis