Eosinophilic granulomatosis with polyangiitis
Eosinophilic granulomatosis with polyangiitis (EGPA), previously known as the Churg-Strauss syndrome (CSS), refers to a small to medium vessel necrotizing pulmonary vasculitis. It is also classified under the spectrum of eosinophilic lung disease and as a type of pulmonary angiitis and granulomatosis.
The incidence typically peaks around the 3rd to 4th decade with an annual incidence rate of around 0.24 per 100,000 2.
Almost all patients have asthma and eosinophilia. Patients also have extrapulmonary signs and symptoms such as sinusitis, diarrhea, skin purpura, and/or arthralgias.
- asthma: present in almost all patients 2
- blood eosinophilia ( >10% of the total white blood cell count): present in almost all patients 2,13
- transient pulmonary infiltrates
- paranasal sinus abnormalities: pain or radiographic abnormality
- presence of extravascular eosinophils on a biopsy specimen
- pANCA: ~75%
Chest radiographs are nonspecific but may show:
- peripheral consolidation, which may be transient/migratory
- small pleural effusions
Imaging features are nonspecific:
- peripheral or random parenchymal opacification (consolidation or ground glass)
- this tends to be the most frequent feature 1; can be transient
- parenchymal opacification is predominantly peripheral or random in distribution 1
- less common features include
- cavitation is rare and if present other co-existing pathology should be considered, e.g. granulomatosis with polyangiitis, infection 6
Delayed myocardial enhancement is a commonly described finding; can be intramyocardial, subepicardial or subendocardial 9-10.
Treatment and prognosis
Corticosteroids (most commonly prednisone) are the mainstay of treatment. Patients with cardiac, renal, gastrointestinal, or CNS involvement, require additional immunosuppression (e.g. cyclosporine, azathioprine).
The condition generally has a low mortality rate compared with other systemic vasculitides 11. Cardiac involvement may, however, be a significant contributor to disease-related death and may occur in up to 60% of cases 8,13.
History and etymology
It was first described in 1951 by Jacob Churg and Lotte Strauss, American physicians based in New York 4.
- for plain radiographic appearances, consider eosinophilic pneumonia
- 1. Worthy SA, Müller NL, Hansell DM et-al. Churg-Strauss syndrome: the spectrum of pulmonary CT findings in 17 patients. AJR Am J Roentgenol. 1998;170 (2): 297-300. AJR Am J Roentgenol (abstract) - Pubmed citation
- 2. Chung MP, Yi CA, Lee HY et-al. Imaging of pulmonary vasculitis. Radiology. 2010;255 (2): 322-41. doi:10.1148/radiol.10090105 - Pubmed citation
- 3. Jeong YJ, Kim KI, Seo IJ et-al. Eosinophilic lung diseases: a clinical, radiologic, and pathologic overview. Radiographics. 27 (3): 617-37. doi:10.1148/rg.273065051 - Pubmed citation
- 4. Churg J, Strauss L. Allergic granulomatosis, allergic angiitis, and periarteritis nodosa. Am. J. Pathol. 27 (2): 277-301. Free text at pubmed - Pubmed citation
- 5. Kim YK, Lee KS, Chung MP et-al. Pulmonary involvement in Churg-Strauss syndrome: an analysis of CT, clinical, and pathologic findings. Eur Radiol. 2007;17 (12): 3157-65. doi:10.1007/s00330-007-0700-4 - Pubmed citation
- 6. Amundson DE. Cavitary pulmonary cryptococcosis complicating Churg-Strauss vasculitis. South. Med. J. 1992;85 (7): 700-2. South. Med. J. (link) - Pubmed citation
- 7. Mahr A, Moosig F, Neumann T et-al. Eosinophilic granulomatosis with polyangiitis (Churg-Strauss): evolutions in classification, etiopathogenesis, assessment and management. Curr Opin Rheumatol. 2014;26 (1): 16-23. doi:10.1097/BOR.0000000000000015 - Pubmed citation
- 8. Neumann T, Manger B, Schmid M et-al. Cardiac involvement in Churg-Strauss syndrome: impact of endomyocarditis. Medicine (Baltimore). 2009;88 (4): 236-43. doi:10.1097/MD.0b013e3181af35a5 - Pubmed citation
- 9. Marmursztejn J, Vignaux O, Cohen P et-al. Impact of cardiac magnetic resonance imaging for assessment of Churg-Strauss syndrome: a cross-sectional study in 20 patients. Clin. Exp. Rheumatol. 2010;27 (1 Suppl 52): S70-6. Pubmed citation
- 10. Marmursztejn J, Cohen P, Duboc D et-al. Cardiac magnetic resonance imaging in Churg-Strauss-syndrome. Impact of immunosuppressants on outcome assessed in a prospective study on 8 patients. Clin. Exp. Rheumatol. 2010;28 (1 Suppl 57): 8-13. Pubmed citation
- 11. Solans R, Bosch JA, Pérez-Bocanegra C et-al. Churg-Strauss syndrome: outcome and long-term follow-up of 32 patients. Rheumatology (Oxford). 2001;40 (7): 763-71. doi:10.1093/rheumatology/40.7.763 - Pubmed citation
- 12. Sinico RA, Di Toma L, Maggiore U et-al. Renal involvement in Churg-Strauss syndrome. Am. J. Kidney Dis. 2006;47 (5): 770-9. doi:10.1053/j.ajkd.2006.01.026 - Pubmed citation
- 13. Broncano J, Vargas D, Bhalla S, Cummings KW, Raptis CA, Luna A. CT and MR Imaging of Cardiothoracic Vasculitis. (2018) Radiographics : a review publication of the Radiological Society of North America, Inc. 38 (4): 997-1021. doi:10.1148/rg.2018170136 - Pubmed