Clinical Trial: Activation and Function of Eosinophils in Conditions With Blood or Tissue Eosinophilia

Study Status: Recruiting
Recruit Status: Recruiting
Study Type: Observational




Official Title: Eosinophil Activation and Function in Parasitic Infections and Other Conditions With Increased Tissue or Peripheral Blood Eosinophilia in Humans

Brief Summary:

This study will investigate how, why and under what conditions eosinophils (a type of white blood cell) become activated and will examine their function in immune reactions. Eosinophil counts often rise in response to allergies, asthma, and parasitic worm infections. They can also go up in uncommon autoimmune conditions and, rarely, in association with tumors. Elevated levels of these cells is called eosinophilia. Usually, eosinophilia causes no apparent symptoms, but in rare cases there may be local swelling and itching, allergic lung problems, heart disease or nerve damage caused by the release of toxic substances in these cells into body tissues.

Patients 1 to 100 years of age with eosinophil counts greater than 750/ml or an abnormal accumulation of eosinophils in the skin or body tissues may be eligible for this study. All participants will have a thorough medical history, physical examination and blood tests. Depending on the person's age and symptoms, other diagnostic tests may be done, including specialized studies of the eye, lungs, skin, bone marrow, nerves or heart. This is not a treatment study, and no experimental treatments will be offered. Patients who require treatment will receive standard medical care.

Certain other procedures may be requested solely for research purposes. All participants will be asked to donate extra blood for laboratory studies investigating how immune cells and other immune substances in the blood act to stimulate a rise in eosinophils. In addition, some participants may undergo one or more of the following:

  • <TAB>Annual Follow-up evaluations - Physical examinations and blood tests to evaluate changes in the patient's condition and eosinophil counts over time.
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