Pathogenesis of Physical Induced Urticarial Syndromes
- Urticaria is a common itchy skin disorder that may occur spontaneously or on exposure to a physical trigger (called physical urticaria).
- Researchers are studying the genetic basis of a physically induced urticarial syndrome. Once called familial cold urticaria, this condition is now called familial cold autoinflammatory syndrome (FCAS). FCAS is an autoinflammatory disease, a group of inherited disorders characterized by unprovoked episodes of inflammation. Patients with FCAS often have hives, joint pain, and fever following general exposure to cold.
- Patients with FCAS have a mutation in a gene that makes a protein called cryopyrin. Cryopyrin seems to be involved with the production of a proinflammatory mediator called interleukin-1 (IL-1). Patients with FCAS and others with autoinflammatory syndromes have benefited from medication that blocks the effects of IL-1.
- To investigate mechanisms that may cause physical hives or urticaria.
- To reproduce urticaria through challenge testing (procedures to test the skin for a reaction to a stimulus), followed by mast cell studies, measurement of IL-1, genetic studies, and other molecular studies to lead to a better understanding of urticaria and to design safe and more effective treatments.
- Patients between 6 months and 65 years of age with a documented history of clinically reproducible physical urticaria that triggers hives and that has been evaluated by a physician. Patients should have a letter of referral, including copies of pertinent medical history and laboratory studies, from a referring physician.
- Affected and nonaffected family members of such patients.
- Exclusion criteria include (1) the presence of conditions that may put the subject at undue risk, such as acute infection, severe thrombocytopenia (a lower than normal number of platelets in the blood), or significant cardiovascular disease; (2) any condition that would make the subject unsuitable for enrollment in this study; and (3) a history of HIV, other known immunodeficiency, or evidence of chronic Hepatitis B and/or C infection.
Researchers will conduct the following tests to verify which triggers cause the hives:
- History and physical exam to determine the relationship between the trigger and appearance of the hives.
- Blood samples for baseline screening (additional samples may be taken within 8 hours of triggering hives).
- Verification of hives using standard challenge testing.
- Procedures to trigger urticaria (the challenge testing) include dermatographism (stroking the skin), delayed pressure urticaria (direct pressure), cold-induced urticaria (cold exposure), cholinergic urticaria (exercise, hot water), solar urticaria (sun exposure), localized heat urticaria (direct heat exposure), aquagenic urticaria (room temperature water), and vibratory angioedema (direct vibratory stimulus exposure).
- Participants who have a positive history for hives and failed challenge testing (that is, hives resulted from the triggers) will be asked to provide a skin biopsy and additional bloods samples for research purposes.
- Participants will be asked to return to the clinic within 1 month if multiple triggers could not be verified during the initial visit, or to return for additional research evaluations, which may include a skin punch biopsy and blood sample collection. Patients may have to stay at the hospital overnight, if required to document the disease.
- Nonaffected family members who enroll in this protocol will provide samples for comparison with the family member who has a history of hives.
- Participants will receive a small financial compensation for the skin biopsy.
|Study Design:||Time Perspective: Prospective|
|Official Title:||Pathogenesis of Physical Induced Urticarial Syndromes|
|Study Start Date:||April 2009|
Urticaria is a common skin disorder that is classified according to its chronicity into acute and chronic forms. It may occur spontaneously or on exposure to a physical factor. In the latter case, the urticaria is classified as a "physical urticaria". Physical urticaria may be induced by mechanical and applied pressure, exercise, or exposure to cold, heat, sun, water, or vibration. The urticarial lesions are generally thought to be the result of mast cell activation and degranulation, which is supported by the finding of increased levels of serum histamine during some urticarial flares. Passive transfer experiments, whereupon serum from affected donors is transferred into recipient's skin followed by physical stimulation with resultant urticaria at the site of challenge, have been positive in some instances. This suggests the presence of an intrinsic factor in serum, such as IgE, which then mediates activation of tissue mast cells. However, the pathogenesis in general remains unclear and a genetic basis for these disorders has not been elucidated.
Recently, the genetic basis for an autoinflammatory syndrome characterized by cold induced urticarial lesions along with fevers and joint inflammation has been found, These patients have mutations in the cold-induced autoinflammatory syndrome t (CIASI) gene that encodes a protein called cryopyrin. Cryopyrin is part of a multiprotein complex termed the inflammasome that regulates IL-1 beta production, and plays a critical role in innate immunity. In Schnitzler's syndrome, another autoinflammatory disorder, patients present with chronic urticaria and monoclonal gammopathy. These patients and those with cryopyrinopathies respond dramatically with IL-1beta antagonist therapy.
The focus of this protocol will be to determine the role of the inflammasome and mast cell activation in the pathogenesis of physical induced urticaria. Subjects will undergo a clinical evaluation that will include verification of their urticaria. Blood and tissue samples, if available, will be collected for analysis. The analysis will be targeted toward the determination of IL-1beta and other cytokine levels, screening for mutations in the inflammasome, gene expression studies and immunohistochemistry in tissue samples. In addition, a search for levels of expression of mast cell activating proteins and sequencing for polymorphisms may be incorporated.
|Contact: Hirsh D Komarow, M.D.||(301) firstname.lastname@example.org|
|United States, Maryland|
|National Institutes of Health Clinical Center, 9000 Rockville Pike||Recruiting|
|Bethesda, Maryland, United States, 20892|
|Contact: For more information at the NIH Clinical Center contact Patient Recruitment and Public Liaison Office (PRPL) 800-411-1222 ext TTY8664111010 email@example.com|
|Principal Investigator:||Hirsh D Komarow, M.D.||National Institute of Allergy and Infectious Diseases (NIAID)|