Churg-Strauss syndrome

Date Updated: 09/15/2025

Overview

Eosinophilic granulomatosis with polyangiitis, shortened to EGPA, is a rare condition that causes inflammation in small- to medium-size blood vessels. This inflammation can lessen blood flow to important organs and tissues, such as the heart, kidneys and nerves. If not treated, this condition can damage organs and tissues. EGPA used to be called Churg-Strauss syndrome.

The first sign of EGPA typically is asthma that develops in adulthood. Many people also have nasal allergies, sinus infections and nasal polyps. As EGPA progresses, it may cause rashes, stomach pain or bleeding, and numbness or tingling in the hands and feet.

Although there is no cure for EGPA, treatment with steroids and other medicines that calm the immune system can help manage symptoms and lessen complications. These treatments depend on how serious the condition is and which organs are affected.

Symptoms

EGPA symptoms are different for each person. Some people have mild symptoms, while others may develop serious or even life-threatening symptoms. Without treatment, symptoms typically get worse over time. The condition often progresses through three stages:

Allergic stage. This first stage often lasts for years. It typically includes new or worsening asthma, nasal allergies and repeated sinus infections.
Eosinophilic stage. In this stage, the body makes too many eosinophils. Eosinophils are a type of white blood cell that plays a role in allergic reactions. Eosinophils can build up in tissues and organs, causing damage. Common issues in this stage include lung symptoms such as coughing or wheezing and digestive issues such as stomach pain or bleeding, nausea and vomiting.
Vasculitic stage. This final stage involves vasculitis, which is the medical term for inflammation of small- to medium-size blood vessels. Vasculitis lessens blood flow and may harm the heart, kidneys, skin, nerves and other organs.

These stages may overlap, and not everyone goes through all three stages.

Other symptoms may include:

Loss of appetite and weight loss.
Joint and muscle pain.
Fatigue, weakness or a general feeling of being unwell.
Skin rash or sores.
Pain, numbness or tingling in the hands and feet.
Nasal polyps.
Hearing loss.

When to see a doctor

See your healthcare professional if you have asthma or nasal allergies that suddenly get worse. See your healthcare professional if you develop breathing difficulties or a runny nose that doesn't go away, especially if you have facial pain as well. And see your healthcare professional if you have unusual rashes, digestive issues, or burning, numbness or tingling in your hands and feet.

These symptoms can be caused by many conditions. But if EGPA is suspected, early diagnosis and treatment are key to preventing serious complications.

Causes

The exact cause of EGPA isn't fully known. It's likely a combination of genetic and environmental factors. For some people, things such as allergens or certain medicines may trigger an overreaction in the immune system. And instead of protecting the body from bacteria and viruses, the immune system starts attacking healthy tissues. Over time this can lead to inflammation in the blood vessels and damage to organs and tissues.

Risk factors

Anyone can develop EGPA, but it most often is diagnosed in people around age 50. You may be at risk if you have:

A history of asthma, especially asthma that started when you were an adult.
Ongoing nasal or sinus issues.
Allergies.
Nasal polyps.
A family history of autoimmune diseases.
Contact with things that may trigger allergies or immune responses.

Having these risk factors doesn't mean you'll develop EGPA, but they may increase your chances.

Complications

EGPA can affect many parts of the body, including the lungs, sinuses, skin, digestive system, kidneys, muscles, joints and heart. If not treated, the condition can lead to permanent damage and may be life-threatening.

Complications depend on the organs involved. Complications may include:

Nerve damage, also called neuropathy. EGPA can damage the nerves in your hands and feet. This can cause numbness, burning, pain and muscle weakness.
Heart disease. Inflammation caused by EGPA can affect the heart and lead to chest pain, heart attack or heart failure.
Kidney damage. If EGPA affects your kidneys, it can cause a condition called glomerulonephritis. This can lessen your kidneys' ability to filter waste, leading to serious health issues.

Prevention

There is no known way to prevent EGPA since the exact cause is unknown. But you can take these steps to reduce the risk of complications:

Get regular medical care if you have asthma or allergies.
Tell your healthcare professional about any new or worsening symptoms.
Follow your treatment plan closely if you are diagnosed with EGPA.
Avoid known triggers that cause allergy or asthma flare-ups.

Early diagnosis and treatment are the best ways to prevent serious health issues from this condition.

Diagnosis

There is no single test to diagnose EGPA. Healthcare professionals typically use a combination of tests to look for signs of inflammation, high eosinophil levels and damage to organs. These tests may include:

Blood tests. A blood test can detect certain antibodies in your blood that can suggest, but not confirm, a diagnosis of EGPA. A blood test also can check for high levels of eosinophils. High levels of this type of white blood cell can support the diagnosis of EGPA but are not specific to it. Other conditions, including asthma, also can increase eosinophils.
Imaging tests. X-rays, MRI scans or CT scans can show issues in the lungs or sinuses. If heart issues are suspected, your healthcare professional may order an echocardiogram to look at how your heart is working.
Tissue biopsy. If other tests suggest EGPA, a small sample of tissue may be taken from your lungs, skin or another affected area. The sample is examined under a microscope to look for inflamed blood vessels, called vasculitis, to confirm the diagnosis.

Your care team considers your medical history, symptoms and response to treatment when making a diagnosis.

Treatment

Although there's no cure for EGPA, medicines can help reduce inflammation, manage symptoms and prevent complications.

Corticosteroids

The main treatment for EGPA is a steroid called prednisone. This medicine helps lessen inflammation quickly. You may start on a high dose to get the condition under control. Then, your healthcare professional gradually lowers the dose to the smallest amount needed to keep your symptoms under control.

Taking corticosteroids at high doses or for a long time can lead to serious side effects. These include weight gain, high blood sugar or diabetes, and cataracts. Side effects also can include infections that are hard to treat and bone loss, called osteoporosis.

Your healthcare team will monitor you closely and may recommend steps to reduce these risks.

Other medicines that calm the immune system

For people with mild symptoms, a corticosteroid alone may be enough. Other people may need more than just steroids. Your healthcare professional may add other medicines to help calm the immune system, especially if your symptoms are more serious or if steroids alone aren't enough.

The only medicines approved by the U.S. Food and Drug Administration specifically for EGPA are mepolizumab (Nucala) and benralizumab (Fasenra). These medicines target eosinophils and often are used with other treatments. Other medicines that may be used include:

Azathioprine (Azasan, Imuran).
Cyclophosphamide (Cytoxan).
Methotrexate (Trexall).
Rituximab (Rituxan).

These medicines can weaken your immune system, so your healthcare team monitors you for infections and other side effects. The goal is to control the inflammation, prevent flare-ups and protect your organs.

Self care

Long-term use of corticosteroids can cause side effects. You can lower your risk by taking good care of your overall health:

Protect your bones. Ask your healthcare professional how much vitamin D and calcium you should get in your diet. Talk with your healthcare professional about whether you should take supplements to help prevent bone loss.
Stay active. Exercise helps keep your bones strong and your weight in a healthy range. Activities such as walking, jogging and strength training are especially helpful to improve bone health.
Eat a healthy diet. Steroids can cause high blood sugar levels and, eventually, type 2 diabetes. A healthy diet can help manage your weight and keep blood sugar levels steady. Choose foods such as fruits, vegetables, lean proteins and whole grains.

Coping and support

Living with an illness like EGPA can be challenging. These tips may help you cope:

Learn about the condition. Understanding EGPA helps you manage your care and prepare for changes.
Build a support system. Family and friends can be a great source of comfort and support. You also may benefit from talking to a counselor or medical social worker who's familiar with the disease. Many people find it helpful to join a support group for people living with EGPA. Talk with members of your care team about online or in-person support groups they may recommend.

Preparing for your appointment

If you have symptoms of EGPA, make an appointment with your healthcare professional. Early diagnosis and treatment can improve your outcome.

You may be referred to a specialist, such as a rheumatologist, immunologist or pulmonologist. A rheumatologist is a doctor who specializes in joint and immune system diseases. An immunologist is a doctor who specializes in immune system diseases. A pulmonologist is a doctor who specializes in lung conditions.

Here's some information to help you get ready for your appointment.

What you can do

When you make an appointment, ask if you need to do anything ahead of time, such as avoid eating or drinking. Ask if you should plan to stay for observation after any tests.

Bring a list of:

Your symptoms and when they started, even those that seem unrelated to EGPA.
Key medical information, including other conditions with which you've been diagnosed.
All medicines, vitamins and other supplements you take, including doses.
Questions to ask your healthcare professional.

If you've seen other healthcare professionals for your condition, bring notes or letters you have summarizing their findings. Bring copies of recent chest X-rays or sinus X-rays if you have them. Take a family member or friend along to help you remember all of the information you receive.

Basic questions to ask your healthcare professional may include:

What do you think is causing my symptoms?
Are there other possible causes?
What tests will I need?
What treatment do you recommend?
What healthy changes can I make to help reduce or manage my symptoms?
How often should I come in for follow-up tests?

What to expect from your doctor

A healthcare professional who sees you for possible EGPA is likely to ask you:

When did your symptoms start?
Have your asthma or allergy symptoms gotten worse?
Do you have breathing issues or sinus infections?
Do you have stomach issues such as nausea or diarrhea?
Have you noticed numbness, pain or weakness in your arms or legs?
Have you lost weight without trying?
Do you have any history of allergies, asthma or autoimmune conditions?