Eosionophilic Granulomatosis with Polyangiitis (EGPA)

Question 1

pathogenesis

Answer 1

Eosinophilic granulomatous inflammation of respiratory tract, small and medium vessels.
Associated with asthma

Question 2

who gets it?

Answer 2

associated with asthma

Question 3

how is it classified?

Answer 3

Localized – Upper/Lower respiratory tract disease without any other systemic involvement or constitutional symptoms
Early systemic -any, without organ or life threatening
Generalized – renal (creatinine < 500) or other organ threatening
Systemic – renal (creatinine > 500) or other vital organ failure
Refractory – progressive disease unresponsive steroids + cyclo

Question 4

how does it present?

Answer 4

American College of rheumatology criteria – 4 or more:
o asthma: wheezing, expiratory rhonchi
o eosinophilia of more than 10% in peripheral blood
o paranasal sinusitis
o pulmonary infiltrates (may be transient)
o histological proof of vasculitis with extravascular eosinophils
o mononeuritis multiplex or polyneuropathy

Question 5

how is it investigated

Answer 5

ESR, PV, CRP raised
anaemia of chronic disease
U&E for renal involvement
urinalysis 
CXR
biopsy of affected area – skin, kidney
immunology: ANCA