GPA Flashcards
(25 cards)
What is Granulomatosis with Polyangiitis (GPA)?
GPA is a necrotizing granulomatous vasculitis of small to medium vessels, associated with PR3-ANCA (c-ANCA), affecting the upper airways, lungs, and kidneys.
Which antibody is most commonly associated with GPA?
c-ANCA (PR3-ANCA) – positive in ~90% of generalized cases.
What are the hallmark pathological features of GPA?
Necrotizing granulomatous inflammation, vasculitis, and tissue necrosis.
What is the classic triad in GPA?
- Upper respiratory tract involvement
- Lower respiratory tract involvement
- Glomerulonephritis
What upper airway features suggest GPA?
• Persistent sinusitis
• Nasal crusting or epistaxis
• Saddle-nose deformity (from septal perforation)
• Otitis media
What causes saddle-nose deformity in GPA?
Cartilage destruction due to granulomatous inflammation of the nasal septum.
What are typical lung manifestations in GPA?
• Cough, hemoptysis, dyspnea
• Cavitating pulmonary nodules or infiltrates
• Alveolar hemorrhage (life-threatening)
How does GPA differ from EGPA in lung findings?
GPA shows fixed cavitating nodules; EGPA shows transient infiltrates and eosinophilia.
What type of glomerulonephritis is seen in GPA?
Rapidly progressive glomerulonephritis (RPGN) with crescent formation.
What urine findings suggest renal involvement in GPA?
Hematuria, proteinuria, red cell casts.
What skin findings may be seen in GPA?
Palpable purpura, ulcers, livedo reticularis.
What neurological complications may occur in GPA?
Mononeuritis multiplex, peripheral neuropathy.
Name 2 rare cardiac complications in GPA.
Pericarditis, coronary arteritis (less common than in EGPA).
What is the most specific diagnostic test for GPA?
Positive PR3-ANCA (c-ANCA); tissue biopsy is definitive.
What are typical biopsy findings in GPA?
Necrotizing granulomatous inflammation and vasculitis.
What does a chest X-ray show in GPA?
Multiple bilateral cavitating nodules or infiltrates.
What confirms renal involvement in GPA?
Renal biopsy showing pauci-immune crescentic glomerulonephritis.
What are key differentials of GPA?
• EGPA (with asthma/eosinophilia)
• Microscopic polyangiitis (no granulomas, more renal involvement)
• Tuberculosis (for cavitating lung nodules)
• Sarcoidosis (non-necrotizing granulomas)
How is induction therapy initiated in GPA?
• High-dose corticosteroids (IV methylprednisolone)
• Plus cyclophosphamide or rituximab
When is plasmapheresis considered in GPA?
In severe renal failure or alveolar hemorrhage (controversial, case-by-case).
What agents are used for maintenance therapy?
Azathioprine, methotrexate, or mycophenolate.
What biologic can be used for relapse or refractory GPA?
Rituximab (anti-CD20 monoclonal antibody).
What is the relapse rate in GPA?
High – ~50% within 5 years after initial remission.
What is the role of ANCA titres in monitoring GPA?
May correlate with disease activity but are not always reliable alone.
