Investigation of Hematologic Parameters in Mastocytosis and Idiopathic Anaphylaxis
N/A
N/A
Both
Mastocytosis, Anaphylaxis
Trial Information
Investigation of Hematologic Parameters in Mastocytosis and Idiopathic Anaphylaxis
Anaphylaxis is a severe systemic hypersensitivity reaction caused by release of mediators
from mast cells and basophils. Signs and symptoms of anaphylaxis may include generalized
flushing, hives, stuffy nose, red and itchy eyes, difficulty in breathing, swelling of the
tongue, throat, palms and soles, gastrointestinal cramping, lightheadedness and loss of
consciousness. Although most common causes of anaphylaxis include foods, drugs and stinging
insects, a causative factor is not identified in up to 50% of the patients with recurrent
anaphylactic episodes. Mast cells are important mediators of anaphylaxis. This study will
examine the hypothesis that some patients with unexplained anaphylaxis may have systemic
mastocytosis, a disorder of pathologic mast cell proliferation, as an underlying cause. In
addition, it will investigate hematopoietic cells, which result in their tissue mast cells
being more susceptible to degranulation. The study will enroll patients with mastocytosis
with or without flushing or anaphylaxis, and patients with unexplained flushing or
anaphylaxis. Patients will receive a clinical evaluation, blood tests and a bone marrow
biopsy and aspirate. Research studies planned include flow cytometric analysis of blood and
bone marrow cells, investigation of mutations or polymorphisms in genes involved in mast
cell growth and differentiation, determination of surrogate disease markers and examination
of mast cell growth and function. The study will improve the understanding of the
mechanisms involved in anaphylactic reactions, which could in turn lead to development of
strategies to better prevent or treat the episodes.
Inclusion Criteria
INCLUSION CRITERIA FOR PATIENTS WITH MASTOCYTOSIS:
Age equal to or greater than 18 years.
Diagnosis of mastocytosis established by presence of typical urticaria pigmentosa skin
lesions or a bone marrow biopsy.
Letter of referral from prospective study participant's local doctor.
Ability to give informed consent.
EXCLUSION CRITERIA FOR PATIENTS WITH MASTOCYTOSIS:
Age less than 18 years.
Lack of a referral physician.
Presence of co-morbid conditions which, in the judgment of the investigator or the
referring physician, may put the patient at undue risk for travel (such as an acute
infection, severe thrombocytopenia).
Inability to provide informed consent.
Inability or refusal to undergo a bone marrow biopsy and aspirate.
Known allergy to latex or Lidocaine.
INCLUSION CRITERIA FOR PATIENTS WITH UNEXPLAINED FLUSHING OR ANAPHYLAXIS:
Age equal to or greater than 18 years.
Presence of flushing or anaphylaxis with negative workup for known causes such as
carcinoid syndrome, pheochromocytoma, food allergy.
Ability to give informed consent.
EXCLUSION CRITERIA FOR PATIENTS WITH UNEXPLAINED FLUSHING OR ANAPHYLAXIS:
Same as for patients with mastocytosis.
Known cause for anaphylaxis or flushing.
Frequent life-threatening anaphylactic episodes: History of 6 or more separate attacks
resulting in ER visits in the 6 months preceding the referral.
INCLUSION CRITERIA FOR RELATIVE:
To have a first-degree relative accepted to the protocol as a patient with unexplained
anaphylaxis, flushing or mastocytosis.
Ability to give informed consent. For minors, ability of the parent to give informed
consent.
There are no age restrictions.
Type of Study:
Observational
Study Design:
N/A
Authority:
United States: Federal Government
Study ID:
030010
NCT ID:
NCT00047918
Start Date:
October 2002
Completion Date:
August 2004
Related Keywords:
- Mastocytosis
- Anaphylaxis
- Mast Cells
- Bone Marrow
- Flushing
- Mutations
- Mastocytosis
- Anaphylaxis
- Anaphylaxis
- Mastocytosis
- Urticaria Pigmentosa
- Mastocytoma
Name | Location |
|---|---|
| National Institute of Allergy and Infectious Diseases (NIAID) | Bethesda, Maryland 20892 |
