What are the symptoms of Churg‑Strauss syndrome (eosinophilic granulomatosis with polyangiitis)?

Symptoms of Churg-Strauss Syndrome (Eosinophilic Granulomatosis with Polyangiitis)

Churg-Strauss syndrome presents with a characteristic triad of adult-onset asthma, eosinophilia, and vasculitic manifestations affecting multiple organ systems, with clinical suspicion heightened when patients with asthma and eosinophilia develop peripheral neuropathy, lung infiltrates, cardiac involvement, or other end-organ complications. 1

Core Manifestations

Respiratory Features (Present in >90% of patients)

• Asthma that typically arises in adulthood, rarely shows seasonal exacerbations, and progressively worsens over time 1
• Chronic rhinosinusitis with nasal polyps that commonly recur after surgical excision 1
• Otitis media and other ear-nose-throat manifestations 1
• Lung infiltrates (40-50% of patients) that are often multiple, migratory, and respond to systemic glucocorticoids 1

Hematologic Abnormality

• Eosinophilia (>10% or >1,500 cells per μl) observed in almost all patients, though it can be masked by systemic glucocorticoid use 1

Vasculitic Complications

Neurologic Involvement (50-70% of patients)

• Peripheral neuropathy with a mononeuritis multiplex pattern 1
• Usually sensory but may cause motor deficits 1
• Demonstrates axonal damage pattern on nerve conduction studies 1

Cutaneous Manifestations

• Skin lesions that are heterogeneous in presentation 1
• Palpable purpura is the most vasculitis-specific skin lesion 1

Cardiac Involvement

• Myocarditis and pericarditis 1
• Cardiac involvement is more frequent in ANCA-negative patients and has been associated with increased mortality, though prognosis appears better with optimized management 1, 2

Renal Disease

• Manifests as proteinuria, hematuria, and/or varying degrees of kidney failure 1
• Glomerulonephritis is more common in ANCA-positive patients 2

Gastrointestinal Involvement

• Gastroenteritis 1
• Gastrointestinal tract involvement is considered a poor prognostic factor 3

Constitutional Symptoms

• Fatigue 1
• Weight loss 1
• Myalgia and arthralgia 1

Clinical Phenotype Variations by ANCA Status

ANCA-Positive Patients (~40% of cases)

• More frequent vasculitis features including glomerulonephritis, peripheral neuropathy, and purpura 1, 4, 2
• More likely to have alveolar hemorrhage 2

ANCA-Negative Patients (~60% of cases)

• More frequent eosinophilic features such as cardiac involvement and gastroenteritis 1, 4, 2
• Heart failure occurs more commonly in this subgroup 4, 2

Clinical Pitfalls

Important caveat: The classic three-phase evolution (allergic phase → eosinophilic phase → vasculitic phase) often does not occur in the described sequence, phases frequently overlap, and some patients never manifest vasculitic complications 1. Therefore, clinicians should not wait for sequential phase progression before considering the diagnosis.

Critical warning: Eosinophilia may be masked by systemic glucocorticoid therapy, so absence of eosinophilia in a patient on steroids does not exclude the diagnosis 1.