Eosinophilic Granulomatosis with Polyangiitis (EGPA), also known as Churg-Strauss Syndrome, is a rare chronic autoimmune disease that causes severe ashtma and vasculitis, i.e., inflammation of blood vessels. This disease particularly affects small and medium-sized blood vessels and leads to organ damage. As a multisystem disease, EGPA can affect various parts of the body, making diagnosis more difficult.
EGPA Symptoms: how does the disease manifest?
EGPA symptoms are varied and often hard to pinpoint. The most common early signs include asthma-like symptoms and hay fever, which may persist for years. The disease progresses in three phases:
- Allergic phase:
Early signs include hay fever, asthma, and hives (urticaria). Urticaria is a skin condition causing red, itchy welts. It may be triggered by allergies or inflammatory processes. The exact cause of urticaria in EGPA is not fully understood but is likely linked to the immune response. - Eosinophilic phase:
In this phase, eosinophils—a type of white blood cell—invade tissues in large numbers. This can damage organs such as the lungs, digestive system, or heart. The lungs are especially frequently affected, leading to breathing problems, cough, and lung infiltrates. - Vasculitic phase:
In advanced stages, vasculitis occurs, affecting mainly small arteries and veins. This can lead to severe organ damage, including heart issues, kidney damage, or neurological impairments.
Typical signs of Churg-Strauss
- Asthma and breathing difficulties
- Hay fever (an allergic reaction that causes sneezing, runny or stuffy nose, itchy or watery eyes, and itchy throat or ears
- Hives (urticaria)
- Joint and muscle pain
- Weight loss and general malaise
- Nerve damage (polyneuropathy)
- Abdominal pain or digestive issues
- Heart problems or heart failure
Causes and Triggers
The exact causes of EGPA are not fully known. It is believed to be triggered by an immune system malfunction, therefore, people predisposed to asthma or allergies (like hay fever) have a higher risk. Urticaria triggers such as allergies or infections may also play a role. EGPA is often associated with inflammatory necrosis in blood vessels caused by the immune system.
EGPA Diagnosis: How is the disease identified?
Diagnosis is based on specific clinical criteria and lab tests. The American College of Rheumatology (ACR) criteria include:
- Presence of asthma
- Eosinophils making up more than 10% of white blood cells
- Lung abnormalities
- Symptoms of polyneuropathy
- Sinusitis
- Vascular infiltrates with eosinophils
At least four of these criteria must be met for a diagnosis. Imaging like X-rays or CT scans of the lungs can provide additional insights. A biopsy of affected tissue (e.g., skin or nerves) may also help confirm the diagnosis.
Treatment of EGPA
Treatment mainly involves high-dose glucocorticosteroids, which suppress the immune system and reduce vessel inflammation. In more severe cases or when steroid response is inadequate, additional immunosuppressive medications, intravenous immunoglobulins, or monoclonal antibodies such as mepolizumab may be used. These targeted therapies help control eosinophilic inflammation.
Most patients show significant improvement with steroid therapy. Moreover, about 90% experience noticeable symptom relief.
Frequency: people living with Churg-Strauss around the globe
EGPA is a rare disease. According to Schindler & Venhoff (2023), the frequency is about 10.7 to 17.8 cases per million people. Incidence rates vary by region: in Europe and North America, it’s estimated at 10–15 cases per million annually; in Latin America and Asia, data are limited, but prevalence appears to be lower—likely due to underdiagnosis or reporting differences.
For example, in Germany, approximately 500 to 600 new cases are diagnosed each year, with an average patient age of about 48 years. Despite its rarity, symptoms are more common in people with asthma or allergic conditions such as hay fever.
Similarly, according to the Polish Ministry of Health, approximately 700 people in Poland are affected by Eosinophilic Granulomatosis with Polyangiitis (EGPA) and Hypereosinophilic Syndrome (HES) combined.
In contrast, for Brazil, Colombia, and Canada, specific national incidence data for EGPA is limited. However, based on the estimated global incidence of 2.7 cases per million people per year, we can approximate the annual number of new EGPA cases in each country as follows:
| Country | Estimated Population (2025) | Estimated New Cases per Year |
|---|---|---|
| Brazil | 218,803,058 | ~591 cases |
| Colombia | 53,425,635 | ~144 cases |
| Canada | 40,126,723 | ~108 cases |
These estimates highlight the rarity of the condition, but also underscore the importance of awareness and early diagnosis—especially in individuals with asthma or allergic conditions.
Prognosis and Life Expectancy
EGPA is not curable, but early diagnosis and treatment can significantly improve outcomes. With ongoing therapy, many patients achieve long-term remission with controlled symptoms. Conversely, without treatment, life expectancy is notably reduced, and organ damage progresses.
The prognosis depends heavily on disease severity and organs affected. Severe outcomes occur when the heart, kidneys, or central nervous system are involved. Heart complications are the leading cause of death. Nevertheless, with appropriate treatment, the 5-year survival rate exceeds 80%.
Early Diagnosis and Targeted Therapy are Key
Churg-Strauss syndrome (EGPA) is a complex, serious illness that requires early diagnosis and comprehensive treatment. Symptoms like asthma, hay fever, hives, and organ damage are crucial warning signs. Targeted therapies using steroids and immunosuppressants can slow disease progression and significantly improve quality of life.
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References:
Schindler, V., & Venhoff, N. (2023). Eosinophile Granulomatose mit Polyangiitis. Aktuelle Rheumatologie, 48(1), 50–59. Available at Thieme Connect. Accessed March 22, 2025.
Chung, S. A., et al. (2023). Evidence-based guideline for the diagnosis and management of eosinophilic granulomatosis with polyangiitis. Nature Reviews Rheumatology, 19, 393–406. Available at Nature Reviews Rheumatology. Accessed March 22, 2025.
Clinical practice guidelines for EGPA. Available at American College of Rheumatology (ACR). Accessed March 22, 2025.
Eksperci postulują leczenie biologiczne dla rzadkich chorób eozynofilowych. Available at Serwis Zdrowie. Accessed March 22, 2025.