Eosinophilic granulomatosis with polyangiitis (EGPA)

Synonyms: Churg-Strauss syndrome, EGPA, allergic granulomatosis, eosinophilic vasculitis, ANCA vasculitis
Specialty: Internal medicine · Rheumatology & immunology
Images: Histology 3
Last updated: 10/2026 · Dr. Pascal Bafteh

Contents

Images (3)
Definition
Classification
Occurrence & epidemiology
Aetiopathogenesis
Clinical features
Diagnosis
Keep learning in the app
Further reading (open access)
Cross-references

Images (3)

Eosinophilic granulomatosis with polyangiitis (EGPA) – Histology in EGPA with eosinophilic infiltrates — Histology in EGPA with eosinophilic infiltratesImage: Nephron (Wikimedia Commons) · CC BY-SA 3.0 · Source

Eosinophilic granulomatosis with polyangiitis (EGPA) – Histology (H&E), low magnification: multiple discrete foci of necrotising vasculitis surrounded by an inflammatory infiltrate — Histology (H&E), low magnification: multiple discrete foci of necrotising vasculitis surrounded by an inflammatory infiltrateImage: Yale Rosen from USA (Wikimedia Commons) · CC BY-SA 2.0 · Source

Eosinophilic granulomatosis with polyangiitis (EGPA) – Histology (H&E), high magnification: dense mixed infiltrate rich in eosinophils next to a necrotic blood vessel — Histology (H&E), high magnification: dense mixed infiltrate rich in eosinophils next to a necrotic blood vesselImage: Yale Rosen from USA (Wikimedia Commons) · CC BY-SA 2.0 · Source

1 / 3

Definition

Eosinophilic granulomatosis with polyangiitis (EGPA, formerly Churg-Strauss syndrome) is a systemic necrotizing vasculitis of small and medium-sized vessels with extravascular granulomas, eosinophilia, and tissue infiltration by eosinophils. According to the 2012 Chapel Hill Consensus Conference, it is an eosinophil-rich, necrotizing granulomatous inflammation of the respiratory tract with necrotizing vasculitis in association with asthma and eosinophilia. It belongs to the ANCA-associated vasculitides.

Classification

2022 ACR/EULAR classification criteria (classification at 6 points or more):

Asthma or obstructive airway disease: +3
Nasal polyps: +3
Mononeuritis multiplex: +1
Blood eosinophilia (≥ 1 × 10⁹/L): +5
Extravascular eosinophil-predominant inflammation on biopsy: +2
c-ANCA or anti-PR3 positive: −3
Hematuria: −1

A score of at least 6 has a sensitivity of 85 % and a specificity of 99 %.

Phases (may overlap): prodromal phase with allergic rhinitis, nasal polyps, and asthma (sometimes for years), eosinophilic phase with blood and tissue eosinophilia, vasculitic phase with organ involvement and constitutional symptoms.

Occurrence & epidemiology

EGPA affects up to 20 people per million, depending on the population studied. Peak incidence is between 40 and 50 years of age.

Aetiopathogenesis

The cause is unknown. An allergic mechanism is suspected in which eosinophils and neutrophil degranulation products directly injure tissue; activated T lymphocytes maintain the eosinophilic inflammation. The disease occurs in people with adult-onset asthma, allergic rhinitis, nasal polyposis, or a combination. ANCA are present in 30–40 %.

Clinical features

Respiratory tract: asthma in most patients, often adult-onset and severe; nondestructive sinusitis; transient patchy pulmonary infiltrates; dyspnea.
Nervous system: mononeuritis multiplex in up to three-fourths; CNS involvement rare (hemiparesis, confusion, seizures).
Skin in about half: nodules and papules on extensor surfaces (palisading granulomas with central necrosis), purpura due to leukocytoclastic vasculitis.
Heart: eosinophilic myocarditis with heart failure, endomyocardial fibrosis, coronary vasculitis, valvular disorders, pericarditis; a major cause of severe disease.
Gastrointestinal in up to one-third: abdominal pain, diarrhea, bleeding, acalculous cholecystitis due to eosinophilic gastroenteritis or mesenteric ischemia.
Kidney less often than in other ANCA-associated vasculitides: pauci-immune focal segmental necrotizing glomerulonephritis.
Arthralgias, myalgias; fever, malaise, weight loss in the vasculitic phase.

Diagnosis

Complete blood count with differential: eosinophilia; additionally IgE, CRP, and ESR to assess inflammatory activity.
ANCA in up to 35 %, usually p-ANCA with antibodies against myeloperoxidase; neither sensitive nor specific.
Urinalysis with sediment and creatinine to detect renal involvement; electrolytes.
Chest radiograph: often transient patchy infiltrates.
Echocardiography in all patients as a baseline.
Biopsy of lung or other affected tissue confirms the diagnosis.

Keep learning in the app

In the InnereFuchs app you can learn Eosinophilic granulomatosis with polyangiitis (EGPA) with flashcards, exam questions and image tasks (ECG, chest X-ray, ultrasound, lab values) – free, in your browser or as an app.

Open in browser About InnereFuchs →