Study Status: Recruiting
Recruit Status: Recruiting
Study Type: Observational
Official Title: Studies in the Pathogenesis of Idiopathic Anaphylaxis
Brief Summary:
This study will explore the possible cause of unexplained, or idiopathic, anaphylaxis. Anaphylaxis is a rapid, life-threatening, severe reaction that occurs suddenly after contact with an allergy-causing substance, usually a particular food, drug or stinging insect. The allergen triggers mast cells to release several substances, including histamine. Histamine is responsible for many of the symptoms that may occur, such as flushing, hives, swelling of the palms and soles or tongue and vocal cords, nasal congestion, itching and tearing of the eyes, shortness of breath and wheezing, stomach pain, vomiting, low blood pressure, loss of consciousness, shock, and, rarely, death. Severe episodes of anaphylaxis are treated with epinephrine (adrenaline), followed by oral antihistamines and steroids. In more than half of cases of anaphylaxis, a clear cause is not identified. These cases are called idiopathic anaphylaxis. There is no cure or long-term preventive therapy for patients with recurrent episodes of idiopathic anaphylaxis.
People between 18 and 55 years of age who have idiopathic anaphylaxis episodes at least 6 times a year (with at least one episode every 3 months) may be eligible for this study.
Participants are evaluated at the NIH Clinical Center with the following tests and procedures: