Table of ContentsView AllTable of ContentsWhat It IsCausesMost Common SignComplicationsOther SymptomsDiagnosisTreatmentCan It Be Prevented?OutlookQuestions to AskWhen to See a Provider
Table of ContentsView All
View All
Table of Contents
What It Is
Causes
Most Common Sign
Complications
Other Symptoms
Diagnosis
Treatment
Can It Be Prevented?
Outlook
Questions to Ask
When to See a Provider
Hypereosinophilicsyndromes are a varied group of rare blood diseases. The primary factor they have in common is a very high level of a type of white blood cell calledeosinophils. While usually an essential part of the immune system, too many eosinophils in various parts of the body can cause organ damage.
These syndromes can cause disease and symptoms in the skin, heart, lungs, and gastrointestinal (GI) tract. Most hypereosinophilic syndromes are not cancer. But some people may develop blood cancer (leukemia) after diagnosis.
This article covers the signs, symptoms, causes, complications, and treatment options for hypereosinophilic syndromes. It will discuss if hypereosinophilic syndromes can be cured and the link between these diseases and leukemia or cancer.
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What Is Hypereosinophilic Syndrome?
Hypereosinophilic syndrome is when the body has too many eosinophils in the blood or tissues for a prolonged time. These white blood cells are typically crucial to the immune system, playing an active role in allergies and fighting off diseases, especially parasites. As part of that role, they cause inflammation.
Having too many eosinophils in the bloodstream is calledeosinophilia. It can be a symptom of many diseases and conditions. People are typically diagnosed with hypereosinophilic syndrome when these other diseases are ruled out as the cause of their high levels of eosinophils.
In hypereosinophilic syndromes, the eosinophils aren’t functioning generally as immune system cells. They build up in tissues and cause damage. In these cases, healthcare providers can’t find a cause for the high number of white blood cells. They build up to high levels that can damage the body’s organs.
Studies have found that hypereosinophilic syndromes develop between 0.3 and 6.3 out of every 100,000 people.
What Causes Hypereosinophilic Syndrome?
There is no single cause of hypereosinophilic syndrome. In most cases, healthcare providers can’t find a reason for the high levels of eosinophils.Research suggests that different people develop this disease for different reasons. They may be genetic, an early sign of cancer, an unknown infection, or other health problems.
Hypereosinophilic syndromes are classified into one of six types based on the underlying cause, as follows:
The only known risk factor for developing hypereosinophilic syndrome is being an adult male between the ages of 20 and 50. About 90% of HES cases are males in middle age.
Most people with MHES are male, but there is no clear difference in occurrence between sexes for other types of HES.People of all sexes can get various types of HES, which has also been seen in kids.(Note that when health authorities and research are cited, the terms for sex or gender from the source are used.)
Hypereosinophilic syndrome is not leukemia. But some people who develop hypereosinophilic syndrome discover that they have a blood disorder—commonly cancer of the white blood cells called leukemia. It may take several years after hypereosinophilic syndrome is first found for healthcare providers touncover leukemia.
What’s the Most Common Sign of Hypereosinophilic Syndrome?
A skin rash or swelling is the most common and obvious sign of hypereosinophilic syndrome.About 50% to 69% of people with hypereosinophilic syndrome have a rash. Not all people with hypereosinophilic syndrome do. It depends on what organs the eosinophils occupy.
The rash also looks different in different people. It can be red, swollen itchy lumps, like swelling under the skin (angioedema), or look more likehivesor a skin allergy.
This photo contains content that some people may find graphic or disturbing.See PhotoReproduced with permission from © DermNetdermnetnz.org2023.
This photo contains content that some people may find graphic or disturbing.See Photo
This photo contains content that some people may find graphic or disturbing.
Reproduced with permission from © DermNetdermnetnz.org2023.
Complications Associated With Hypereosinophilic Syndrome
Hypereosinophilic syndromes affect organs other than the skin. HES in the heart, lungs, stomach, intestines, and other organs can lead to organ dysfunction. Almost half (44%) of people with HES have lung symptoms, and 38% have intestinal issues. Eventually, about 20% develop heart issues.
These complications can cause additional symptoms and include:
Other Signs and Symptoms of Hypereosinophilic Syndrome
Other common symptoms of hypereosinophilic syndromes include:
How Is Hypereosinophilic Syndrome Diagnosed?
Historically, a diagnosis of hypereosinophilic syndrome requires two blood tests four weeks to six months apart that both show a blood level of more than 1,500 eosinophils per microliter.
An average blood eosinophil number is 350 to 500 per microliter. A number anywhere between 500 and 1500 may be called mild eosinophilia. Moderate eosinophilia may fall between 1,500 and 5,000 eosinophils per microliter. Severe eosinophilia is above 5,000 eosinophils per microliter.
Healthcare providers then have to rule out other causes of eosinophilia before they can diagnose HES.Common reasons for eosinophilia include:
Ruling out these causes can require a lot of testing. This includes multiple stool samples or blood tests, allergy testing, and imaging of affected organs to rule out other causes of the symptoms. Abone marrow biopsy(removing a sample for examination in the lab) can rule out cancers or indicate an innate disease of eosinophils.
Genetic testing looks for changes associated with hypereosinophilic syndromes. Imaging studies, like chest X-rays andechocardiograms, assess damage to the heart and lungs. Healthcare providers will also check your liver and kidney function,vitamin B12 levels,erythrocyte sedimentation rate, and serum tryptase levels.
How Is Hypereosinophilic Syndrome Treated?
Treatment for hypereosinophilic syndrome depends on the cause of the disease. It typically focuses on lowering the high eosinophil levels in your blood and tissues to reduce the damage they do. It also aims to reduce inflammation directly and slow disease progression.
Treatments vary based on the organs that are affected. Other health issues can also complicate treatment. It can be hard to predict how serious the disease will be in a given person.
People who are not having symptoms do not need treatment. A healthcare provider will closely monitor these people for organ damage and complications.
Corticosteroids
Treatment with corticosteroids like prednisone is often the first treatment choice. With steroid use, studies have found that 70% to 85% of people see their eosinophil numbers returning to normal levels and control those levels for a long time.
This isn’t a cure, though. Eosinophilia and symptoms come back once steroids are stopped. And long-term, high-dose steroid use can lead to bone loss, infections, adrenal insufficiency, hip joint collapse, and stunted growth. Side effects include swelling, weight gain, increased appetite, diabetes, moon face (full, rounded face), and mood disturbances.
Chemotherapy
Chemotherapies used for HES include Hydrea (hydroxyurea).They are often used with corticosteroids or for people who do not respond to steroids.
Chemotherapy can have harmful side effects, including:
Chemotherapy is used only in severe cases and requires careful monitoring.
Interferon Alpha (IFNa)
Interferon alpha can cause influenza-like side effects such as fever, chills, muscle aches, headaches, and joint pain. It can also lead to low blood counts and elevated liver enzymes that require careful monitoring and are especially problematic when a person already has liver damage from the eosinophils. About 25% to 30% of people stop taking Interferon alpha due to side effects.
Targeted Treatments
Monoclonal Antibodies
When HES does not react to traditional treatments, specific monoclonal antibody treatments may help. These include:
Can I Prevent Hypereosinophilic Syndrome?
There is no way to prevent hypereosinophilic syndromes. If you know you’re at risk, work with a healthcare provider to monitor and treat symptoms before developing organ damage.
What’s the Outlook for Hypereosinophilic Syndrome?
HES prognosis depends on what’s causing the disease. It cannot be cured, but medications can control most types. How the disease responds to these treatments plays a significant role in how the condition plays out.
Prognosis depends on what organs the eosinophils are attacking and how much damage they’ve done. If the damage is already severe, it can’t be undone, and HES may be fatal. The most common cause of death in cases of HES is heart failure. Today, more than 80% of HES patients survive five years or more.
Other causes of death for people with HES, according to studies, include infection (20%), other cancers (20%), blood clots (13%), and vascular disease (13%).
Questions to Ask Your Healthcare Provider
If you’ve been diagnosed with HES, you may consider asking your provider:
When to See a Healthcare Provider
If you’re diagnosed with HES and your symptoms worsen, talk to your healthcare provider immediately. If you think you have signs and symptoms of HES, schedule an exam.
When to Seek Emergency CareIf you have HES and have heart symptoms like chest pain, heartburn, nausea, and swelling, go to the emergency room immediately.
When to Seek Emergency Care
If you have HES and have heart symptoms like chest pain, heartburn, nausea, and swelling, go to the emergency room immediately.
Summary
Hypereosinophilic syndromes are a group of rare blood diseases. They have an abnormally high level of eosinophil white blood cells, which can cause inflammation and damage tissues and organs. The organs affected include the skin, heart, lungs, and gastrointestinal tract.
The most common sign of hypereosinophilic syndrome is a skin rash or swelling. Other symptoms include weakness, fatigue, cough, trouble breathing, muscle aches, and fever. Complications include heart failure, kidney damage, and blood clots.
Healthcare providers diagnose hypereosinophilic syndrome after ruling out other potential causes. The cause of hypereosinophilic syndromes is often unknown, but some have a genetic origin. Treatment aims to reduce eosinophil levels and inflammation. Typical treatments include corticosteroids, chemotherapy, and targeted therapies. Monoclonal antibodies can help.
Hypereosinophilic syndrome outlook depends on organ damage and response to treatment. While there is no cure, it can be managed with medications.
8 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.American Academy of Allergy Asthma & Immunology.Hypereosinophilic syndrome symptoms, diagnosis, treatment & management.American Partnership for Eosinophilic Disorders.Hypereosinophilic syndromes.Schuster B, Zink A, Eyerich K.Medical algorithm: diagnosis and treatment of hypereosinophilic syndrome.Allergy. 2020;75(11):3003-3006. doi:10.1111/all.14368Klion AD.How I treat hypereosinophilic syndromes.Blood. 2015; 126(9):1069–1077. doi:10.1182/blood-2014-11-551614Gotlib J.World Health Organization-defined eosinophilic disorders: 2017 update on diagnosis, risk stratification, and management.Am J Hematol. 2017;92(11):1243-1259. doi:10.1002/ajh.24880Klion A.Hypereosinophilic syndrome: approach to treatment in the era of precision medicine.Hematology Am Soc Hematol Educ Program. 2018;2018(1):326-331. doi:10.1182/asheducation-2018.1.326DermNet.Hypereosinophilic syndrome.Podjasek JC, Butterfield JH.Mortality in hypereosinophilic syndrome: 19 years of experience at Mayo Clinic with a review of the literature.Leuk Res. 2013;37(4):392-395. doi:10.1016/j.leukres.2012.12.016
8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.American Academy of Allergy Asthma & Immunology.Hypereosinophilic syndrome symptoms, diagnosis, treatment & management.American Partnership for Eosinophilic Disorders.Hypereosinophilic syndromes.Schuster B, Zink A, Eyerich K.Medical algorithm: diagnosis and treatment of hypereosinophilic syndrome.Allergy. 2020;75(11):3003-3006. doi:10.1111/all.14368Klion AD.How I treat hypereosinophilic syndromes.Blood. 2015; 126(9):1069–1077. doi:10.1182/blood-2014-11-551614Gotlib J.World Health Organization-defined eosinophilic disorders: 2017 update on diagnosis, risk stratification, and management.Am J Hematol. 2017;92(11):1243-1259. doi:10.1002/ajh.24880Klion A.Hypereosinophilic syndrome: approach to treatment in the era of precision medicine.Hematology Am Soc Hematol Educ Program. 2018;2018(1):326-331. doi:10.1182/asheducation-2018.1.326DermNet.Hypereosinophilic syndrome.Podjasek JC, Butterfield JH.Mortality in hypereosinophilic syndrome: 19 years of experience at Mayo Clinic with a review of the literature.Leuk Res. 2013;37(4):392-395. doi:10.1016/j.leukres.2012.12.016
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
American Academy of Allergy Asthma & Immunology.Hypereosinophilic syndrome symptoms, diagnosis, treatment & management.American Partnership for Eosinophilic Disorders.Hypereosinophilic syndromes.Schuster B, Zink A, Eyerich K.Medical algorithm: diagnosis and treatment of hypereosinophilic syndrome.Allergy. 2020;75(11):3003-3006. doi:10.1111/all.14368Klion AD.How I treat hypereosinophilic syndromes.Blood. 2015; 126(9):1069–1077. doi:10.1182/blood-2014-11-551614Gotlib J.World Health Organization-defined eosinophilic disorders: 2017 update on diagnosis, risk stratification, and management.Am J Hematol. 2017;92(11):1243-1259. doi:10.1002/ajh.24880Klion A.Hypereosinophilic syndrome: approach to treatment in the era of precision medicine.Hematology Am Soc Hematol Educ Program. 2018;2018(1):326-331. doi:10.1182/asheducation-2018.1.326DermNet.Hypereosinophilic syndrome.Podjasek JC, Butterfield JH.Mortality in hypereosinophilic syndrome: 19 years of experience at Mayo Clinic with a review of the literature.Leuk Res. 2013;37(4):392-395. doi:10.1016/j.leukres.2012.12.016
American Academy of Allergy Asthma & Immunology.Hypereosinophilic syndrome symptoms, diagnosis, treatment & management.
American Partnership for Eosinophilic Disorders.Hypereosinophilic syndromes.
Schuster B, Zink A, Eyerich K.Medical algorithm: diagnosis and treatment of hypereosinophilic syndrome.Allergy. 2020;75(11):3003-3006. doi:10.1111/all.14368
Klion AD.How I treat hypereosinophilic syndromes.Blood. 2015; 126(9):1069–1077. doi:10.1182/blood-2014-11-551614
Gotlib J.World Health Organization-defined eosinophilic disorders: 2017 update on diagnosis, risk stratification, and management.Am J Hematol. 2017;92(11):1243-1259. doi:10.1002/ajh.24880
Klion A.Hypereosinophilic syndrome: approach to treatment in the era of precision medicine.Hematology Am Soc Hematol Educ Program. 2018;2018(1):326-331. doi:10.1182/asheducation-2018.1.326
DermNet.Hypereosinophilic syndrome.
Podjasek JC, Butterfield JH.Mortality in hypereosinophilic syndrome: 19 years of experience at Mayo Clinic with a review of the literature.Leuk Res. 2013;37(4):392-395. doi:10.1016/j.leukres.2012.12.016
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