Eosinophilic granulomatosis with polyangiitis (EGPA), formerly known as Churg-Strauss syndrome, is a rare condition characterized by asthma, high levels of eosinophils, and inflammation of small- to medium-sized blood vessels. The disease affects an estimated one to three people per million. EGPA can involve many organ systems, including the lungs, sinuses, skin, heart, gastrointestinal tract, kidneys, and nervous system.
The cause of EGPA is unknown, although eosinophils are considered to play a prominent role in the disease symptoms.
Asthma is the hallmark of EGPA, occurring in more than 95 percent of people with this disease. Symptoms of asthma, which include wheezing, breathlessness, chest tightness, and coughing, may occur months or years before the onset of vasculitis, or inflammation of the blood vessels.
Additional EGPA symptoms vary depending on which tissues and organs the disease affects. Up to two-thirds of people with EGPA develop skin lesions such as lumps and blisters. Other possible symptoms include abdominal pain, diarrhea, joint and muscle aches, and nerve damage.
Inflammation of blood vessels in the heart can lead to heart attack or heart failure. This accounts for approximately half of the deaths attributable to EGPA.
There are no specific tests for EGPA. When diagnosing EGPA, doctors consider a person’s symptoms and results from blood tests, imaging tests, and biopsy—the removal of a small piece of tissue—of an involved organ.
People with EGPA have high levels of eosinophils in their blood. Some also have elevated anti-neutrophil cytoplasmic antibodies (ANCAs), which attack immune cells called neutrophils. ANCAs are common in other forms of vasculitis, such as granulomatosis with polyangiitis, and occur in 40 to 60 percent of people with EGPA.
Chest X-rays or computed tomography (CT) scans that show inflammation or tissue damage in the lungs or sinuses can be useful for diagnosing EGPA. Doctors also may perform additional tests, such as urinalysis, lung function testing, nerve conduction studies, or examination of the gastrointestinal tract, to assess the extent of disease and determine which organs are involved.
Biopsy of the lungs or other affected tissues, such as the skin or peripheral nerves, is important to confirm EGPA and rule out similar disorders. By examining the biopsy sample under a microscope, healthcare professionals can identify signs of vasculitis and confirm the presence of eosinophils in the tissue.
While there is no cure for EGPA, the disease can be controlled with appropriate treatment. The standard treatment for EGPA is corticosteroids. Once symptoms are under control, the corticosteroid dose is gradually decreased. Many patients continue to take low doses of corticosteroids to maintain remission.
However, if EGPA affects the heart, kidney, gastrointestinal tract, or central nervous system or if high doses of corticosteroids are required, doctors may prescribe additional immunosuppressive therapy. The drug cyclophosphamide, in combination with corticosteroid treatment, can induce remission in patients with severe EGPA. Once remission is achieved, patients typically are switched to immunosuppressive drugs with fewer side effects, such as azathioprine or methotrexate. Doctors also may use these drugs to reduce the amount of corticosteroids that people with EGPA need to take. Long-term use of high-dose corticosteroids can cause numerous side effects, including increased susceptibility to infection, weight gain, cataracts, brittle bones, diabetes, and changes in mood and personality.
In addition, most people with EGPA receive treatment for asthma symptoms according to standard asthma guidelines.
Read more about asthma.
NIAID researchers and their colleagues at the National Institute of Arthritis and Musculoskeletal and Skin Diseases continue to evaluate potential new EGPA treatments. Learn more about current efforts in the Research section.
Last Updated April 23, 2014
Last Reviewed April 23, 2014