Churg-Strauss Syndrome

Diagnosis

Indications for Testing

• Asthma with multiorgan systemic disease

Criteria for Diagnosis

• American College of Rheumatology, 1990 – ACR criteria for the classification of Churg-Strauss syndrome (4 of 6 required)
  • Asthma
  • Eosinophilia >10% (on differential)
  • Mono- or polyneuropathy attributable to systemic vasculitis
  • Migratory or transient pulmonary infiltrates
  • Paranasal sinus disease
  • Extravascular eosinophils on biopsy of vascular tissue

Laboratory Testing

• Nonspecific testing
  • CBC – may have eosinophilia
  • Urinalysis – may have hematuria
  • ESR – elevated
• ANCA – 75% have pANCA with MPO+ (PR3 is rarely positive)

Histology

• Tissue biopsy of involved organ site – confirm presence of small-to-medium sized artery vasculitis, necrotizing granulomas, and eosinophilic infiltration of arterial and venous walls

Imaging Studies

• Chest radiograph – infiltrates common; pleural effusion in 10%

Prognosis

• Relapses are common, especially if maintenance treatments are fully withdrawn
• Flare-ups may follow reductions of corticosteroid doses

Differential Diagnosis 

• Vasculitis
  • Wegener granulomatosis
• Parasitic infection
  • Toxocara spp
  • Schistosoma spp
  • Trichinella spiralis
  • Strongyloides stercoralis
  • Wuchereria bancrofti
  • Paragonimus westermani
• Eosinophilic syndromes
  • Bronchopulmonary aspergillosis
  • Hypersensitivity pneumonitis
  • Hypereosinophilic syndrome

Clinical Background

Churg-Strauss syndrome (allergic angiitis granulomatosis) is distinguishable from other pulmonary eosinophilic syndromes by the presence of eosinophilic vasculitis along with asthma and multiorgan involvement (lungs, heart, gastrointestinal tract, skin, nervous system).

Epidemiology

• Incidence – 1-3/1,000,000 in U.S.; in asthma patients, may be as high as 67/1,000,000
• Age – 40-50 years
• Sex – M>F

Pathophysiology

• Small vessel necrotizing vasculitis/angiitis; involvies arteries and veins
• Extravascular necrotizing granulomas and eosinophilic infiltration

Clinical Presentation

• Phases of disease
  • Prodromal phase
    • Characterized by asthma and allergic rhinitis
    • Typically occurs when individual is 20-30 years of age and persists for many years
  • Eosinophilic infiltrative phase
    • Peripheral eosinophilia, eosinophilic tissue infiltration of various organs, including lungs and GI tract
  • Vasculitic phase
    • Constitutional – fever, fatigue, malaise, weight loss
    • Cardiovascular – myocarditis, congestive heart failure
    • Neurologic – peripheral neuropathy (typically mononeuritis multiplex), polyneuropathy, confusion, seizures, cranial nerve palsies, coma
    • Dermatologic – nodules, papules, petechial rash
    • Gastrointestinal – abdominal pain, nausea, emesis, diarrhea
    • Renal – glomerulonephritis
    • Ophthalmologic – uveitis, retinopathy
    • Otorhinologic – paranasal sinus disease

Treatment

• Steroids initially
• Other immunosuppressives may be required

Indications for Laboratory Testing

• Tests generally appear in the order most useful for common clinical situations
• Click on number for test-specific information in the ARUP Laboratory Test Directory