EDUCATION

EOSINOPHILIC GRANULOMATOSIS WITH POLYANGITIIS (EGPA, CHURG-STRAUSS SYNDROME)

Clinical features

Eosinophilic Granulomatosis with Polyangitiis (also known as Churg-Strauss syndrome) is a rare systemic vasculitis characterized by inflammation of the blood vessels, primarily of small size, leading to blood flow restriction and to consequent damage of vital organs and tissues.
EGPA can be associated with pulmonary, ear-nose-throat, cutaneous, cardiac, intestinal, renal and neurological manifestations.
The symptoms of EGPA can range from mild to life-threatening, and may vary among individuals, however almost all patients have asthma and/or sinus polyps, and hypereosinophylia (i.e., an increased level of white blood cells called eosinophils).

Other symptoms include:
  • Fever
  • Fatigue/malaise
  • Rapid and sudden weight loss
  • Muscle and joint pain
  • Skin rashes
  • Numbness or tingling of the hands or feet
  • Sudden loss of strength in the hands or feet
  • Chest pain or palpitations
  • Increasing shortness of breath or coughing
  • Abdominal pain
  • Presence of blood in the stools
  • Kidney disease

Etiopathogenesis

The etiopathogenesis of EGPA is not fully understood.
As a vasculitis, it is classified among autoimmune diseases; indeed, EGPA is known as an ANCA-associated vasculitis, as auto-antibodies attacking the body’s own blood protein (anti-neutrophil cytoplasmic antibody) can be detected in some patients.
However, infectious and environmental risk factors have been described, and they could play a role as triggers of EGPA onset or relapse, particularly on subjects with a genetic susceptibility.

Diagnosis

The diagnosis of EGPA is not based on a single test, but rather considers a number of factors, including clinical history, laboratory tests, imaging, and, when indicated, a biopsy of an affected tissue or organ.

Among the most useful tests to diagnose EGPA are:
  • Urinalysis: Excessive protein or presence of red blood cells may indicate inflammation of the kidneys.
  • Blood tests: The ANCA test (i.e., the search for autoantibodies against anti-neutrophil cytoplasmic proteins), when positive, can be helpful in confirming diagnosis. However, a positive ANCA test is not a specific marker for EGPA diagnosis: indeed, only around 30-50 percent of individuals with EGPA are ANCA positive, and ANCA-test can be positive also in case of other ANCA-associated vasculitis (different from EGPA). Other common tests include blood inflammatory parameters, such as the erythrocyte sedimentation rate (ESR) and the C-reactive protein (CRP) test. All of these tests may support a diagnosis of EGPA, but are not conclusive on their own. A tissue biopsy is typically needed.
  • Tissue biopsy: This surgical procedure removes a small tissue sample from an affected vessel or organ, which is examined under a microscope for signs of inflammation or tissue damage.
  • Imaging studies: X-rays and computed tomography (CT) scans may reveal pulmonary or ear-nose-throat involvement.
  • Heart echocardiogram: All patients with EGPA should be screened for heart involvement.

Treatment

EGPA is a serious but treatable disease. Treatment typically includes corticosteroids to reduce inflammation, mostly used in combination with immune-modulating/immunosuppressants therapies, such as methotrexate azathioprine, mycophenolate mofetil, or cyclophosphamide.
To date, novel therapeutic strategies (including the biologic agents rituximab and mepolizumab) have been developed, to reduce the need of steroids, the possible adverse events related to the long-term use of immune-modulating/immunosuppressants medications, as well as to guarantee a better control of the disease.

Disease course

Even with effective treatment, EGPA is a chronic illness with cycles of relapse and remission. For this reason, regular doctor visits and ongoing monitoring of lab and imaging tests are important to guarantee the disease control and to avoid serious complications.

Most relevant scientific publications and insights

C. Marvisi, R.A. Sinico, C. Salvarani, D. Jayne , D. Prisco, B. Terrier, G. Emmi, A. Vaglio, European EGPA Study Group

C. Marvisi et al.

New perspectives in eosinophilic granulomatosis with polyangiitis (EGPA): report of the first meeting of the European EGPA Study Group

P.A. Lyons, J.E. Peters, F. Alberici, J. Liley, R.M.R. Coulson, W. Astle, C. Baldini, F. Bonatti, M.C. Cid, H. Elding, G. Emmi, J. Epplen, L. Guillevin, D.R.W. Jayne, T. Jiang, I. Gunnarsson, P. Lamprecht, S. Leslie, M.A. Little, D. Martorana, F. Moosig, T. Neumann, S. Ohlsson, S. Quickert, G. A. Ramirez, B. Rewerska, G. Schett, R.A. Sinico, W. Szczeklik, V. Tesar, D. Vukcevic, European Vasculitis Genetics Consortium, B. Terrier, R.A. Watts, A. Vaglio, J.U. Holle, C. Wallace, K.G.C. Smith

P.A. Lyons et al.

Genome-wide association study of eosinophilic granulomatosis with polyangiitis reveals genomic loci stratified by ANCA status

S. Moiseev, X. Bossuyt, Y. Arimura, D. Blockmans, E. Csernok, J. Damoiseaux, G. Emmi, L.F. Flores-Suárez, B. Hellmich, D. Jayne, J.C. Jennette, M.A. Little, A.J. Mohammad, F. Moosig, P. Novikov, C. Pagnoux, A. Radice, K. Sada, M. Segelmark, Y. Shoenfeld, R. A. Sinico, U. Specks, B. Terrier, A.G. Tzioufas, A. Vaglio, M. Zhao, J.W. Cohen Tervaert, European EGPA Study Group

S. Moiseev et al.

International Consensus on ANCA Testing in Eosinophilic Granulomatosis with Polyangiitis

A. Canzian, N. Venhoff, M.L. Urban, S. Sartorelli, A.M. Ruppert, M. Groh, N. Girszyn, C. Taillé, F. Maurier, V. Cottin, C. de Moreuil, V. Germain, M. Samson, M. Jachiet, L. Denis, V. Rieu, P. Smets, G. Pugnet, A. Deroux, C.A. Durel, A. Aouba, P. Cathébras, C. Deligny, S. Faguer, H. Gil, B. Godeau, F. Lifermann, S. Phin-Huynh, M. Ruivard, P. Bonniaud, X. Puéchal, J.E. Kahn, J. Thiel, L. Dagna, L. Guillevin, A. Vaglio, G. Emmi, B. Terrier 1, French Vasculitis Study Group and the European EGPA Study Group

A. Canzian et al.

Use of Biologics to Treat Relapsing and/or Refractory Eosinophilic Granulomatosis With Polyangiitis: Data From a European Collaborative Study

M. Papo, R.A. Sinico, V. Teixeira, N. Venhoff, M.L. Urban, M. Iudici, J. Mahrhold, F. Locatelli, G. Cassone, F. Schiavon, B. Seeliger, T. Neumann, C. Kroegel, M. Groh, C. Marvisi, M. Samson, T. Barba, D. Jayne, A. Troilo, J. Thiel, B. Hellmich, S. Monti, C. Montecucco, C. Salvarani, J.E. Kahn, B. Bonnotte, C.A. Durel, X. Puéchal, L. Mouthon, L. Guillevin, G. Emmi, A. Vaglio, B. Terrier

M. Papo et al.

Significance of PR3-ANCA positivity in eosinophilic granulomatosis with polyangiitis (Churg-Strauss)

M. Zampieri, G. Emmi, M. Beltrami, C. Fumagalli, M.L. Urban, L.L. Dei, A. Marchi, M. Berteotti, A. Tomberli, K. Baldini, A. Bettiol, S. Pradella, E. Silvestri, N. Marchionni, A. Vaglio, I. Olivotto, D. Prisco

M. Zampieri et al.

Cardiac involvement in eosinophilic granulomatosis with polyangiitis (formerly Churg-Strauss syndrome): Prospective evaluation at a tertiary referral centre

F. Maritati, F. Peyronel, P. Fenaroli, F. Pegoraro, V. Lastrucci, G.D. Benigno, A. Palmisano, G.M. Rossi, M.L. Urban, F. Alberici, P. Fraticelli, G. Emmi, M. Corradi, A. Vaglio

F. Maritati et al.

Occupational exposures and smoking in eosinophilic granulomatosis with Polyangiitis (Churg-strauss syndrome)

A. Bettiol, R.A. Sinico, F. Schiavon, S. Monti, E.P. Bozzolo, F. Franceschini, M. Govoni, C. Lunardi, G. Guida, G. Lopalco, G. Paolazzi, A. Vacca, G. Gregorini, P. Leccese, M. Piga, F. Conti, P. Fraticelli, L. Quartuccio, F. Alberici, C. Salvarani, S. Bettio, S. Negrini, C. Selmi, S. Sciascia, G. Moroni, L. Colla, C. Manno, M.L. Urban, A. Vannacci, M.R. Pozzi, P. Fabbrini, S. Polti, M. Felicetti, M.R. Marchi, R. Padoan, P. Delvino, R. Caporali, C. Montecucco, L. Dagna , A. Cariddi, P. Toniati, S. Tamanini, F. Furini, A. Bortoluzzi, E. Tinazzi, L. Delfino, I. Badiu, G. Rolla, V. Venerito, F. Iannone, A. Berti, R. Bortolotti, V. Racanelli, G. Jeannin, A. Padula , A. Cauli, R. Priori, A. Gabrielli, M. Bond, M. Tedesco, G. Pazzola, P. Tomietto, M. Pellecchio, C. Marvisi, F. Maritati, A. Palmisano, C. Dejaco, J. Willeit, S. Kiechl, I. Olivotto, P. Willeit, D. Prisco, A. Vaglio, G. Emmi, Italian EGPA Consortium

A. Bettiol et al.

Risk of acute arterial and venous thromboembolic events in eosinophilic granulomatosis with polyangiitis (Churg-Strauss syndrome)