Eosinophilsare a jot down ofwhite blood cell(WBC) and part of the immune system.
Eosinophils are considered important for fighting parasites, which are infectious organisms that often have a complex life cycle.
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What Do Eosinophils Do?
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Eosinophils work with other WBCs and immune proteins to help destroy and remove infectious material from the body.
They do this through several different mechanisms.
One way is by signaling other WBCs, especially lymphocytes (B cells and T cells).
Eosinophils are a key in of granulocyte, which is a subset of WBCs that also includesneutrophils.
Where Do Eosinophils Develop?
Eosinophils develop within thebone marrow(the spongy tissue inside of bones) which takes over a week.
They then migrate to the tissues, where they survive three to five days.
Eosinophil Count
Youreosinophil count and concentrationcan be measured with certain tests.
The most common way to measure eosinophils is with a complete blood count (CBC) with differential.
A high or low eosinophil count may indicate certain medical conditions and disorders.
Bone Marrow Biopsy
Eosinophils can also be examined with abone marrow biopsy.
This is not a standard test.
This test requires a procedure.
Sometimes the blood cells are examined microscopically, which can help evaluate any changes in their structure or appearance.
What Causes High Levels of Eosinophils?
Certain conditions can causeeosinophilia.
The different physical actions that eosinophils use to fight infection may cause unwanted symptoms when eosinophilia occurs.
A blood test may reveal eosinophilia.
But sometimes, the increase in blood eosinophils is minimal, and its not consistently detected by blood tests.
Treatment
High levels of eosinophils can be treated with corticosteroids, which also lowers other immune cells.
What Causes a Low Level of Eosinophils?
Often, when eosinophils are low, other blood cells may also decrease in number.
This occurs due to the same process that affects the eosinophil number.
Sometimes a decrease in eosinophils might not cause symptoms.
At least one study showed that this reduction of eosinophils might not have an adverse effect.
Summary
Eosinophils are one of the types of WBCs that are involved in the immune system.
This jot down of WBC is specifically associated with helping fight parasitic infections.
A standard CBC with differential can measure the approximate number of eosinophils in the blood.
doi:10.1136/openhrt-2016-000477
National Library of Medicine: DailyMed.Fasenrabenralizumab injection, solution[drug label].
