An observational study in Hypersensitivity, Immediate, Autoinflammatory Syndromes and Physical Urticaria, sponsored by National Institute of Allergy and Infectious Diseases (NIAID). Completed at 1 site in United States. Open to participants aged 2 Years to 90 Years. Per ClinicalTrials.gov, last updated 2026-03-30.
Sponsored by National Institute of Allergy and Infectious Diseases (NIAID) · Observational
Background:
Objectives:
Eligibility:
Design:
Researchers will conduct the following tests to verify which triggers cause the hives:
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.
The goal of this protocol is thus to gain a better understanding of the pathogenesis of physical urticaria through the investigation of subjects with severe and unusual phenotypes and/or inherited patterns of disease. 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 novel serum mediators, mast cell activation and mutational analysis in families with inherited patterns.
35 studies on the registry are indexed under Cryopyrin-Associated Periodic Syndromes; 5 are open to participants now.
Browse Cryopyrin-Associated Periodic Syndromes studies →National Institute of Allergy and Infectious Diseases (NIAID) is the lead sponsor of 2,446 studies on the registry; 179 are open to participants now.
Of its 405 completed or terminated interventional studies of FDA-regulated products, 302 (75%) have results posted.
Compared within Cryopyrin-Associated Periodic Syndromes, this study's primary condition as ClinicalTrials.gg classifies it; the registry's first condition term is Hypersensitivity, Immediate. The counts are of registry records indexed under each term, refreshed daily. How we classify →
Primary clinical
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Affected subjects/guardian must:
Non-affected relatives/guardian must:
Healthy volunteers must:
EXCLUSION CRITERIA:
The following criteria apply to all subjects:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Platelets
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Affected physical urticaria
Healthy volunteer
Unaffected relative
to determine the role of mast cell activation and genetic predisposition in the pathogenesis of physically induced urticaria.
The patient s physical urticaria will be verified through standard testing.
Time frame: 12/31/2028
Plan to share: No — IDP will not be shared since sequencing is performed through NIH Centralized sequencing.
Ran from Jun 2009 to primary completion in Jun 2024, 179 months.
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This study is completed, as verified in Mar 2026. You cannot join it, but the record below documents what was studied.
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Cryopyrin-Associated Periodic Syndromes →
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