eosinophilia

pathology

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July 23, 2026

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Eosinophilia is a condition characterized by an abnormal increase in the number of eosinophils in the blood. Eosinophils are a type of white blood cell that are readily stained by acidic dyes like eosin, which gives them a red appearance under a microscope. They are typically found at sites of allergic reactions and parasitic infections.123

Eosinophils are produced in the bone marrow and migrate to tissues such as the skin and lungs. They play a role in hypersensitivity and inflammatory responses, and are involved in defending the body against parasites like flatworms. An elevated eosinophil count in the blood is characteristic of allergic states and parasitic infections.21

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blood disease
Leukocytosis
Eosinophilic leukocytosis, an increase in the number of eosinophilic leukocytes, is encountered in many allergic reactions and parasitic infections. It is especially characteristic of trichinosis—a disorder resulting from infestation by trichina larvae, which are ingested when poorly cooked infected pork is eaten.
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Eosinophilic leukocytosis, an increase in the number of eosinophilic leukocytes, is encountered in many allergic reactions and parasitic infections. It is especially characteristic of trichinosis—a disorder resulting from infestation by trichina larvae, which are ingested when poorly cooked infected pork is eaten.
Read More