Get advice for managing Multiple Sclerosis: Watch the video.

Hypereosinophilic Syndrome

What is hypereosinophilic syndrome?

Hypereosinophilic syndrome (HES) is a group of conditions where you have too many eosinophils in your blood. Eosinophils are white blood cells that fight infection with parasites (small living creatures). They are also present with certain allergic diseases, such as asthma. They slightly increase in number during these conditions or when you take certain drugs or medicines. With HES, the increased numbers of eosinophils stay in your body for too long and cause damage to your organs. The eosinophils cause damage from swelling inside the organs of your body. This happens most often in the brain, heart, lungs, and skin. You may also have swelling of your kidneys, intestines, liver, and spleen.

What causes hypereosinophilic syndrome?

The exact cause of HES is not known. Problems in your immune system may cause HES. The immune system is your body's defense system against infections and diseases. A chemical imbalance in your body or damage to the cells that make eosinophils may cause HES.

What are the signs and symptoms of hypereosinophilic syndrome?

You may have any of the following:

  • Chest pain.

  • Fever, feeling very weak, tiring very easily, or weight loss.

  • Redness, swelling, itching, or flaking of your skin.

  • Weakness or numbness in parts of your body.

  • Throwing up, having watery stools, or pain in your abdomen (stomach).

  • Trouble breathing or having a dry cough for a long time.

How is hypereosinophilic syndrome diagnosed?

Your caregiver will ask you about your medical, travel, and drug history. Other medical conditions may cause you to have the same symptoms as HES. Your caregiver will check if you have other conditions that cause eosinophils to increase. He will do a physical exam on you. You may also have other tests to check your organs for damage. You may have any of the following:

  • Blood tests: You may need blood taken to give caregivers information about how your body is working. The blood may be taken from your hand, arm, or IV.

  • Bone marrow biopsy: This is a procedure where a sample of bone marrow is removed and sent to a lab for tests. Bone marrow is the soft, spongy tissue inside the bone. The skin over your upper hipbone is first cleaned. Caregivers put numbing medicine into your skin so you will have little pain. You caregiver may also give you medicine for anxiety and pain through an intravenous (IV) tube in your vein (blood vessel). A bandage is put on the biopsy area after the tissue sample is taken. Ask your caregiver for more information about bone marrow biopsy.

  • Echocardiogram:

    • This test is also called an echo. It is a type of ultrasound, using sound waves to show pictures of the size and shape of your heart. An echo also looks at how your heart moves when it is beating. These pictures are seen on a TV-like screen. This test can tell how well your heart is pumping. An echo can also find problems, such as a blood clot in your heart or thickening of your heart muscle. Ask your caregiver for more information about transthoracic echocardiogram.

  • Stool test: This is a test where a sample of your stool is examined to see if you have parasites.

  • Chest x-ray: This is a picture of your lungs and heart. Caregivers use it to see how your lungs and heart are doing. Caregivers may use the x-ray to look for signs of infection like pneumonia, or to look for collapsed lungs. Chest x-rays may show tumors, broken ribs, or fluid around the heart and lungs.

How is hypereosinophilic syndrome treated?

You may have any of the following:

  • Medicines:

    • Immune system and chemotherapy medicines: These medicines may slow the making of eosinophils to decrease the number of eosinophils in your blood.

    • Steroid medicine: This medicine decreases inflammation (redness), pain, and swelling. Inflammation may be found in organs damaged by eosinophils. Steroids may also decrease the number of eosinophils and prevent further damage. This medicine can be very helpful for your condition, but it has side effects. Be sure you understand why you need steroids. Do not stop taking this medicine without your caregivers OK. Stopping on your own can cause problems.

  • Bone marrow transplant: This is a procedure where you receive healthy bone marrow from a donor. Bone marrow is the tissue where blood cells, including eosinophils, are made. You will receive medicine to weaken your own bone marrow before receiving the donor bone marrow. Your caregiver may use this procedure if all other medicines do not decrease your symptoms. Ask your caregiver for more information about bone marrow transplant.

Where can I find support and more information?

HES may be a life-changing condition for you and your family. Accepting that you have HES may be hard. You and those close to you may feel sad, angry, or frightened. These are normal feelings. Talk to your caregivers, family, or friends about your feelings. Contact the following for more information:

  • American Partnership for Eosinophilic Disorders
    3419 Whispering Way Drive
    Richmond , TX 77469
    Phone: 1- 713 - 498-8216
    Web Address:

Care Agreement

You have the right to help plan your care. Learn about your health condition and how it may be treated. Discuss treatment options with your caregivers to decide what care you want to receive. You always have the right to refuse treatment. The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

© 2013 Truven Health Analytics Inc. Information is for End User's use only and may not be sold, redistributed or otherwise used for commercial purposes. All illustrations and images included in CareNotes® are the copyrighted property of A.D.A.M., Inc. or Truven Health Analytics.

Learn more about Hypereosinophilic Syndrome

Learn how medication, diet, and exercise are key to managing Multiple Sclerosis. Click Here