Churg-Strauss Syndrome

Diagnosis

Indications for Testing

  • Asthma with multiorgan systemic disease

Criteria for Diagnosis

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  • Relapses are common, especially if maintenance treatments are fully withdrawn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 

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
Test Name and Number Recommended Use Limitations Follow Up
CBC with Platelet Count and Automated Differential 0040003
Method: Automated Cell Count/Differential

Differentiate between infectious and non-infectious process

   
Urinalysis, Complete 0020350
Method: Reflectance Spectrophotometry/Microscopy

Screen for hematuria

   
Sedimentation Rate, Westergren (ESR) 0040325
Method: Visual Identification

Assess for inflammation

   
Anti-Neutrophil Cytoplasmic Antibody with Reflex to Titer and MPO/PR-3 Antibodies 2002068
Method: Semi-Quantitative Indirect Fluorescent Antibody/Semi-Quantitative Multiplex Bead Assay

Use in initial testing for suspicion for vasculitis

If screen is positive, titer and MPO/PR-3 antibodies testing will be added to aid in antibody determination