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🌱 來自: Huppert’s Notes
Small Vessel Vasculitis ANCA-Associated Vasculitides (AAV)🚧 施工中
Small Vessel Vasculitis: ANCA-Associated Vasculitides (AAV)
Granulomatosis with polyangiitis (GPA, formerly Wegener’s granulomatosis)
• Epidemiology: Incidence of 7–12/million individuals annually. Typical age of onset 45–60 yr.
• Diagnosis:
- Most patients with systemic disease are c-ANCA and anti-PR3 positive
- Tissue biopsy showing pauci-immune necrotizing granulomatous vasculitis is gold standard
• Clinical features:
- ENT (70–100%): Sinusitis, rhinorrhea, otitis media, chondritis of the ears and nose with saddle nose deformity, nasal septal perforation
- Pulm (50–90%): Cavitary nodules, diffuse alveolar hemorrhage, tracheal subglottic stenosis
- Renal (40–100%): Pauci-immune necrotizing glomerulonephritis
- Derm (10–50%): Palpable purpura, nodules, pyoderma gangrenosum
- Neuro (30%): Mononeuritis multiplex, distal symmetric polyneuropathy, pachymeningitis
- Ocular (15–60%): Posterior uveitis, scleritis, episcleritis, retro-orbital pseudotumor, dacryoadenitis (lacrimal gland inflammation)
- Cardiac (<10%): Pericarditis, myocarditis, conduction disorder
- GI (5–10%): Ulceration
• Treatment:
- Systemic organ-threatening disease:
• Induction therapy: Pulse dose glucocorticoids (1 g per day × 3–5 days) followed by 1 mg/kg, then add rituximab or cyclophosphamide. Rituximab is non-inferior to cyclophosphamide for induction therapy in ANCA+ GPA and MPA (RAVE New Engl J Med 2010) and is associated with less infertility and alopecia.
• Maintenance therapy: Rituximab for 12–24 months after remission, azathioprine, or methotrexate
- Limited upper airway disease: Glucocorticoids plus methotrexate or rituximab
Microscopic polyangiitis (MPA)
• Epidemiology: Incidence of 2.7–94/million individuals annually. Average age of onset is 50–60 yr
• Diagnosis:
- Small vessel vasculitis of the lungs (diffuse alveolar hemorrhage) and kidneys (crescentic RPGN)
- 50–75% ANCA+ and generally p-ANCA and anti-MPO positive
- Tissue biopsy is the gold standard and shows non-granulomatous necrotizing pauci-immune vasculitis (as opposed to granulomatous in GPA)
• Clinical features:
- Renal (80–100%): Necrotizing glomerulonephritis
- Derm (30–60%): Palpable purpura with histology showing leukocytoclastic vasculitis; livedo reticularis; nodules; necrotic skin ulcers
- Neuro (30–70%): Mononeuritis multiplex; distal symmetric polyneuropathy; pachymeningitis
- Pulm (25–55%): Diffuse alveolar hemorrhage, organizing pneumonia, ILD with radiographic phenotype of usual interstitial pneumonia (UIP)
- ENT (10–30%): Sinusitis; sensorineural hearing loss
• Treatment: Similar to treatment of GPA
Eosinophilic granulomatosis with polyangiitis (EGPA, formerly Churg-Strauss syndrome)
• Epidemiology: Rarest ANCA-associated vasculitis; 0.1–2.66/million individuals annually
• Diagnosis:
- Small vessel vasculitis that typically occurs in patients with preceeding adult-onset asthma and nasal polyps
- 50% ANCA+ and usually p-ANCA and anti-MPO positive
- Eosinophilia >1500 cells/μL often present
- Diagnostic gold standard is biopsy of involved tissue (e.g., nerve) showing pauci-immune necrotizing granulomatous vasculitis with eosinophilic infiltration of vessel walls and tissues (eosinophilic infiltration distinguishes EGPA from MPA and GPA)
• Clinical features:
- Neuro (70%): Mononeuritis multiplex or distal sensory polyneuropathy
- Pulm: Most patients (95–100%) have preceding asthma that often improves during the vasculitic phase. Patients also may have migratory pulmonary consolidations similar to those seen with eosinophilic pneumonia during the vasculitis phase
- Cardiac (20–40%): Pericarditis, endomyocarditis, conduction system disease, CHF
- Renal (25%): Pauci-immune glomerulonephritis
• Treatment:
- Glucocorticoids alone may be sufficient unless there is major organ involvement, in which case cyclophosphamide is indicated
- Lowest mortality among all the ANCA-associated vasculitidies (5 yr survival 97%)