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

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ClinicalTrials.gov Identifier: NCT00001406
Recruitment Status : Recruiting
First Posted : November 4, 1999
Last Update Posted : March 27, 2023
Information provided by (Responsible Party):
National Institutes of Health Clinical Center (CC) ( National Institute of Allergy and Infectious Diseases (NIAID) )

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:

  • Annual Follow-up evaluations - Physical examinations and blood tests to evaluate changes in the patient's condition and eosinophil counts over time.
  • Bone marrow biopsy and aspiration will be recommended during the initial evaluation, and in certain patients at other times when it is important to look directly at the newly developing cells in the bone marrow. For this procedure an area of skin and bone is anesthetized with xylocaine (an anesthetic similar to that used by dentists), and a very sharp needle is used to sample the bone marrow for evaluation. Bone marrow biopsy and aspiration can have side effects of pain and/or bleeding into the skin and soft tissues at the site of the procedure. Rarely the area at the biopsy site can become infected, and is treated with antibiotics.
  • Genetic testing: Some of the blood drawn from you as part of this study will be used for genetic tests. Genetic tests can help researchers study how health or illness is passed on to you by your parents or from you to your children. Any genetic information collected or discovered about you or your family will be confidential.
  • Leukapheresis (only patients 18 years and older) to collect large numbers of certain cells - In this procedure, whole blood is collected through a needle placed in an arm vein. The blood circulates through a machine that separates it into its components. The white cells are then removed and the rest of the blood is returned to the body, either through the same needle used to draw the blood or through a second needle placed in the other arm.

Condition or disease
Immune System Diseases Eosinophilia Helminthiasis Hypersensitivity Parasitic Disease

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Study Type : Observational
Estimated Enrollment : 800 participants
Observational Model: Cohort
Time Perspective: Prospective
Official Title: Eosinophil Activation and Function in Parasitic Infections and Other Conditions With Increased Tissue or Peripheral Blood Eosinophilia in Humans
Actual Study Start Date : April 21, 1997

Resource links provided by the National Library of Medicine

Volunteers with elevated eosinophil counts in the peripheral blood or tissues; or a relative of a volunteer with eosinophilia

Primary Outcome Measures :
  1. To understand the mechanisms driving eosinophilia and disease pathogenesis in patients with a wide range of eosinophilic disorders [ Time Frame: Ongoing assessment ]
    Identification and characterization of clinical and genetic variants of hypereosinophilic syndromes.

Secondary Outcome Measures :
  1. To assess the signs and symptoms experienced by patients with HES [ Time Frame: Ongoing ]
    Creation of a patient-related outcomes questionnaire for use in future treatment studies of HES

  2. To understand the mechanisms of action of therapeutic agents used or in development for the treatment of HES [ Time Frame: Ongoing ]
    Delineation of the effects of therapeutic agents on eosinophil development, activation, recruitment to the tissues and/or apoptosis

  3. To determine the mechanisms underlying eosinophil activation and recruitment to the blood and tissues [ Time Frame: Ongoing ]
    Identification of biomarkers of disease activity and specific organ involvement in eosinophilic disorders; identification of new therapeutic targets for the treatment of HES

  4. To develop a diagnostic algorithm that accurately classifies eosinophilic patients by underlying etiology [ Time Frame: Ongoing ]
    Identification of laboratory and clinical tests that distinguish between clinical and genetic variants

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

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Ages Eligible for Study:   1 Year to 100 Years   (Child, Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
Participants with marked eosinophilia, eosinophilia in tissues or suspected eosinophilic end organ involvement will be seen on this protocol. Evaluation of family members may be of interest when a genetic cause of eosinophilia in suspected in a study participant.

To be eligible to participate in this study, an individual must meet all of the following criteria:

  1. Stated willingness to comply with all study procedures and availability for the duration of the study
  2. Male or female, aged 1-100
  3. Ability of subject (or Legally Authorized Representative (LAR)) to understand and sign a written informed consent document

    Eosinophilic Patients only:

  4. Documented peripheral blood count >1500/mm3, tissue eosinophilia (abnormal accumulation of eosinophils in the skin or other body tissues) or suspected eosinophilic end organ involvement
  5. Primary (non-NIH) physician for routine medical care

    Relatives only:

  6. Extended family member of an eosinophilic participant on this protocol


An individual who meets any of the following criteria will be excluded from participation in this study:

  1. Any condition(s) or diagnosis, physical and/or psychological, that the investigator feels precludes the patient from participation in the study.

    Relatives only:

  2. Females must not be pregnant

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00001406

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Contact: Nicole C Holland-Thomas, R.N. (301) 402-5969 hollandnc@mail.nih.gov
Contact: Amy D Klion, M.D. (301) 435-8903 aklion@niaid.nih.gov

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United States, Maryland
National Institutes of Health Clinical Center Recruiting
Bethesda, Maryland, United States, 20892
Contact: For more information at the NIH Clinical Center contact Office of Patient Recruitment (OPR)    800-411-1222 ext TTY dial 711    ccopr@nih.gov   
Sponsors and Collaborators
National Institute of Allergy and Infectious Diseases (NIAID)
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Principal Investigator: Amy D Klion, M.D. National Institute of Allergy and Infectious Diseases (NIAID)
Additional Information:
Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):

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Responsible Party: National Institute of Allergy and Infectious Diseases (NIAID)
ClinicalTrials.gov Identifier: NCT00001406    
Other Study ID Numbers: 940079
First Posted: November 4, 1999    Key Record Dates
Last Update Posted: March 27, 2023
Last Verified: March 20, 2023

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Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Keywords provided by National Institutes of Health Clinical Center (CC) ( National Institute of Allergy and Infectious Diseases (NIAID) ):
Helminth Parasites
Natural History
Additional relevant MeSH terms:
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Parasitic Diseases
Immune System Diseases
Leukocyte Disorders
Hematologic Diseases