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.
Eosinophilia is usually found when your doctor has ordered blood tests to help diagnose a condition you're already experiencing. It's not often an unexpected finding or simply discovered by chance.
Talk to your doctor about what these results mean. Evidence of blood or tissue eosinophilia and results from other tests may indicate the cause of your illness, or your doctor may suggest other tests to assess your condition.
Because a separate condition is often the cause of eosinophilia, it's important to determine what other conditions or disorders you may have. If you get an accurate diagnosis and can treat any relevant conditions or disorders, the eosinophilia will likely resolve.
However, if you have persistent hypereosinophilic syndrome, it's important to continually work with doctors and monitor your health, as this condition may cause significant complications over time.
Jan. 22, 2011
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