DefinitionBy Mayo Clinic staff
Eosinophilia (e-o-sin-o-PHIL-e-uh) is a higher than normal level of eosinophils, one of the five major types of disease-fighting white blood cells.
High levels of eosinophils can circulate in your blood (blood eosinophilia), but high eosinophil concentrations may also occur at the site of an infection or inflammation (tissue eosinophilia).
Tissue eosinophilia may be found in tissue samples taken during an exploratory procedure or in samples of certain fluids, such as mucus released from nasal tissues. If you have tissue eosinophilia, the level of eosinophils in your bloodstream is likely normal.
Blood eosinophilia may be detected with a blood test, usually as part of a complete blood count. A count of more than 500 eosinophils per microliter of blood is generally considered eosinophilia in adults. A count of more than 1,500 eosinophils per microliter of blood that lasts for several months is called hypereosinophilic syndrome.
- Weller PF. Approach to the patient with eosinophilia. http://www.uptodate.com/home/index.html. Accessed Dec. 6, 2010.
- Roufosse F, et al. Clinical manifestations, pathophysiology, and diagnosis of the hypereosinophilic syndromes. http://www.uptodate.com/home/index.html. Accessed Dec. 6, 2010.
- Eosinophilic-associated gastrointestinal disorders (EGIDs). American Partnership for Eosinophilic Disorders. http://www.apfed.org/downloads/EGID%20brochure_2008_Web_Final.pdf. Accessed Dec. 6, 2010.
- Wardlaw AJ. Eosinophils and their disorders. In: Lichtman MA, et al. Williams Hematology. 8th ed. New York, N.Y.: McGraw-Hill Companies; 2010. http://www.accessmedicine.com/resourceTOC.aspx?resourceID=69. Accessed Dec. 6, 2010.
- Eosinophilia. The Merck Manuals: The Merck Manual for Healthcare Professionals. http://www.merckmanuals.com/professional/sec11/ch139/ch139b.html#sec11-ch139-ch139b-613. Accessed Dec. 6, 2010.
- Wilkinson JM (expert opinion). Mayo Clinic, Rochester, Minn. Dec. 14, 2010.
- Noel P (expert opinion). Mayo Clinic, Rochester, Minn. Dec. 15, 2010.
- Laboratory Reference Values. Eosinophils. Rochester, Minn. Mayo Foundation for Medical Education and Research. January 2011.