About ANCA-Associated Vasculitis (AAV)

  • 3 types:
    • Granulomatosis with polyangiitis (GPA)
    • Microscopic polyangiitis (MPA)
    • Eosinophilic granulomatosis with polyangiitis (eGPA)
  • Insidious onset, weeks-months
  • eGPA mean age ~40
  • Associated with atopy (asthma, eczema, sinusitis)

Disease Overview & Clinical Presentation

  • Adult with new-onset asthma: consider eosinophilic granulomatosis with polyangiitis (eGPA)
  • Granulomatosis with polyangiitis on DDx (view image) for:
    • New diagnosis of otitis media as adult
    • Recurrent sinusitis +/- epistaxis
    • Pseudotumor
    • Nasal septal perforation
    • Pulmonary renal syndrome
  • Often with:
    • Constitutional symptoms
    • High CRP
    • ESR can be >100
  • cANCA+ PR3: consider GPA
    pANCA+ MPO: consider MPA
  • Look for potential medications for drug-induced vasculitis
  • ANCA neg does not rule out AAV
    • ANCA usually neg in cardiac-associated eGPA or upper airway limited GPA

Treatment

  • Need PJP prophylaxis for AAV lung disease and treatment with rituximab or cyclophosphamide

Common Symptoms

  • Constitutional symptoms
  • Episcleritis/scleritis

Granulomatosis with Polyangiitis (GPA)

  • Pulm-renal
  • Cavitary pulm lesions
  • Upper airway limited (ANCA neg)
  • Pseudotumor
  • Nasal septal perforation

Microscopic Polyangiitis (MPA)

  • Pulm-renal (ANCA pos when renal dz)

Eosinophilic Granulomatosis with Polyangiitis (eGPA)

  • Cardiac involved (ANCA neg):
    • Pericardial effusion
    • Myocarditis
  • Mononeuritis multiplex (foot drop)

Lab Workup

  • ANCA panel
    • cANCA+PR3=GPA
    • pANCA+MPO=MPA
    • pANCA/MPO in EGPA ~50%
  • HH CRP, HH ESR
  • Anemia
  • AKI
  • Urinalysis:
    • +blood
    • +protein
    • +RBC casts

Imaging

  • CT chest (view images)
    • Diffuse infiltrates in DAH 
    • Cavitating lung lesions in GPA

Bronchoscopy

  • Confirm DAH

Kidney Biopsy

  • Pauci-immune crescentic glomerulonephritis (GN)

Drug Induced

  • PTU, hydralazine, minocycline
  • Goodpasture (GBM disease)

Malignancy

  • Lymphoma
  • Leukemia

Other Kidney Disease

  • Lupus nephritis
  • Membranous nephropathy
  • IgA nephropathy
  • Post-infectious glomerulonephritis (GN)
  • Usually with rheumatology supervision
  • Two-part approach: induction and maintenance

Induction

Maintenance Choices

Monitoring

  • PJP prophylaxis needed for pts with lung disease and treatment with rituximab or cyclophosphamide
  • Monitor:
    • Renal function
    • Urinalysis
    • For infection from immunosuppression

Prognosis

  • 90% mortality risk if untreated
  • GPA more likely to relapse
  • MPA more like to progress to interstitial lung disease (ILD)