Eosinophilia
Condition
Definition
Eosinophilia is a higher than normal number of eosinophils. Eosinophils are a type of white blood cell. They help protect the body from certain types of infections. They are also involved in allergic reactions.
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Causes
Eosinophilia may be caused by:
- Problems in genes that control cell growth
- A change in the number of cells due to certain cancers
- Health problems, such as infections, problems with the immune system, or allergies
Risk Factors
Eosinophilia is more common in people who have family members with it.
Other things that may raise the risk are:
- Allergies, including food allergies
- Infections, mainly those caused by parasites
- Inflammatory conditions
- Skin problems
- Certain blood cancers
- Reactions to medicines
- Exposure to certain toxins
Symptoms
Some people may not have symptoms. The symptoms a person will have depend on what is causing the eosinophilia. For example:
- Asthma:
- Wheezing
- Breathing problems
- Infections from a parasite:
- Belly pain
- Loose stools (poop)
- Fever
- Cough
- Rashes
Diagnosis
The doctor will ask about symptoms and past health. A physical exam may be done.
Initial tests may be:
- Blood tests
- Stool tests
- Biopsy
- Bone marrow tests
Other tests may be done, depending on the problems the person is having. They may include:
Treatment
The goal is to treat the underlying cause of the eosinophilia. Corticosteroids may be given to ease inflammation. This will also lower the number of eosinophils.
Prevention
There are no known guidelines to prevent eosinophilia.
American Academy of Allergy, Asthma, and Immunology
American Society of Hematology
CANADIAN RESOURCES:
Canadian Allergy, Asthma, and Immunology Foundation
Health Canada
American Academy of Allergy, Asthma, and Immunology
American Society of Hematology
CANADIAN RESOURCES:
Canadian Allergy, Asthma, and Immunology Foundation
Health Canada
References
- Eosinophilia. Cleveland Clinic website. Available at:https://my.clevelandclinic.org/health/diseases/17710-eosinophilia.
- Eosinophilia. Merck Manual Professional Version website. Available at: https://www.merckmanuals.com/professional/hematology-and-oncology/eosinophilic-disorders/eosinophilia.
- Eosinophilia—approach to the patient. EBSCO DynaMed website. Available at: https://www.dynamed.com/approach-to/eosinophilia-approach-to-the-patient.
- World Health Organization (WHO) 2017 update on diagnosis, risk stratification, and management of WHO-defined eosinophilic disorders can be found in Am J Hematol 2017 Nov;92(11):1243.
Contributors
- Daniel A. Ostrovsky, MD
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