5 Clinical Trials for Various Conditions
This research is being done to see if the amount of an enzyme in blood (called serum mast cell tryptase) changes before and after surgery. The investigators would like to see if these amounts are related to knee stiffness and pain in subjects that undergo a total knee replacement.
Background: - Allergic inflammation is central to allergy-related diseases and disorders, such as asthma, food allergies, and atopic dermatitis. Atopic dermatitis, commonly called eczema is a chronic, noncontagious skin condition, usually starting in the first years of life, which causes itching and scaling of an individual s skin. Because atopic dermatitis is a common condition in children who have allergy-related diseases, including asthma, researchers are interested in studying both individuals with atopic dermatitis and their close relatives (parents and children) to better understand how allergy-related diseases develop and progress. In addition, some patients with inherited disorders with features including atopic dermatitis or other aspects of allergy such as food allergy, asthma, hay fever, hives, and others, will also be seen. Objectives: - To study the natural history of diseases of allergic inflammation, such as atopic dermatitis or genetic disorders associated with allergic inflammation. Eligibility: * Children and adolescents between 1 month and 21 years of age who have a documented history of moderate to severe atopic dermatitis. * Individuals between 1 month and 80 years of age who have a suspected genetic or inherited allergy disorder related to atopic dermatitis or allergic pathways. * Child and adult relatives of eligible participants will also be studied on this protocol. Design: * The study will require one initial visit to the National Institutes of Health Clinical Center (lasting 1-5 days), as well as any required follow-up visits for treatment and research studies. Participants will receive treatment for atopic dermatitis and other allergic diseases as part of the study for up to 1 year. * Participants will have some or all of the following tests as part of this study: * A detailed physical examination and medical history * Allergy skin prick testing to examine participants' responses to different allergens. * Blood samples for additional allergen testing, testing the immune system, and other research purposes * Skin punch biopsy to take a skin sample * Lung function tests to measure airflow from the lungs and inflammation * Food-related tests to diagnose potential food allergies * Leukapheresis to collect white blood cells only * Research samples, including stool specimens, saliva samples, buccal swabs (to collect cells from the inside of the cheek), and skin cell samples * Clinical digital photography to provide images of affected and healthy skin. * Participants will be asked to return for follow-up visits and tests for up to 1 year after the initial visit(s).
This study will examine growth factors that promote and inhibit mast cell proliferation resulting in mastocytosis, a disease of excessive mast cells in the body. These cells can release chemicals that cause itching, blisters, flushing, bone pain and abdominal pain. Patients up to 80 years of age with mastocytosis may be eligible for this 1-day study. Participants will have one visit at NIH lasting up to 8 hours, during which they will undergo the following tests and procedures: * Medical history and physical examination. * Laboratory studies, if medically indicated. * Blood tests to identify genetic changes important in the growth, development, and functioning of mast cells. * Bone marrow aspiration and biopsy. For the bone marrow procedure, the skin over the hipbone and the outer surface of the bone itself are numbed with local anesthesia. Then, a special needle is inserted into the hipbone and about 1 tablespoon of bone marrow is drawn into a syringe. Another needle is inserted into the same area to collect a small piece of the bone marrow. Additional procedures may include allergen testing, urinalysis, and 24-hour urine collection. Participants will receive an evaluation of their mastocytosis.
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 13 and 70 years of age who have idiopathic anaphylaxis, or have anaphylaxis that is caused by specific allergens such as food, venom, or drugs and medications may be eligible for this study. Participants are evaluated at the NIH Clinical Center with the following tests and procedures: * Medical history, physical examination and blood tests. * Bone marrow biopsy. For this test, the skin over the hipbone and the outer surface of the hipbone itself are numbed with local anesthesia. Then, a needle is inserted into the hipbone and a small amount of bone marrow is drawn into a syringe. The needle also cuts a small core of bone marrow, which is removed for analysis. * Other tests that may be needed for evaluation of the patient s condition.
Background: * Omalizumab is an approved drug for the treatment of asthma by the Food and Drug Administration. * Researchers are now studying this drug in a double-blind placebo-controlled manner to assess efficacy in patients with idiopathic anaphylaxis (recurrent hypersensitive allergic episodes for which a cause is not identified). * The study will improve understanding of the mechanisms involved in anaphylactic reactions as a response to the downregulation (a decrease in the number of receptors on the surface of cells) in mast cell (a resident cell with several types of tissues) activation, and lead to the development of strategies to better prevent or treat anaphylaxis. Objectives: * To determine whether treatment with omalizumab will reduce or prevent episodes of unprovoked anaphylaxis (an acute allergic reaction) in subjects with a history of idiopathic anaphylaxis. * To assess pharmacodynamics (physiological effects of a drug) and identify patients with undiagnosed mastocytosis (rare disorders caused by too many mast cells). * To investigate cellular and molecular mechanisms of signaling and the effect of omalizumab on mast cells or basophils (a cell in the leukocyte family that releases histamine, which affects allergic response) and explore other regulatory pathways that may be involved with modulation of mast cell degranulation. Eligibility: * Patients between 18 and 70 years of age who have been diagnosed with idiopathic anaphylaxis, a diagnosis that is made only after other causes of anaphylaxis have been considered. * Patients with documented anaphylaxis episodes (mild to severe) at least six times within the past 1 year period, at least once within the last 4 months, and with at least one of the following: * Elevated serum tryptase above baseline within 2 hours of the event. * Emergency room visit with documented anaphylaxis without a known cause established by the acute onset of an illness (minutes to several hours) with involvement of the skin, mucosal tissue, or both (generalized hives, itching or flushing, swollen lips-tongue-throat) and at least one of the following: (1) respiratory compromise or gastrointestinal involvement (shortness of breath, wheeze-bronchospasm, throat tightness, low oxygen levels, nausea, vomiting, or abdominal pain); or (2) reduced blood pressure or associated symptoms of end-organ dysfunction (collapse, loss of consciousness, or loss of bladder or bowel control). * Hospitalization for anaphylaxis. * Patients must provide a letter of referral, with copies of pertinent medical history and laboratory tests, from the prospective participant s local physician, and have the ability to give informed consent. * Women with childbearing potential must have a negative pregnancy test, and must agree to practice abstinence or effective birth control from the start of the protocol and for 3 months following the last injection of the study drug. Design: * Participants will undergo a clinical evaluation, blood tests, and a bone marrow biopsy and aspirate. * Participants will be randomized to either drug or placebo and will receive two doses of omalizumab or a matched placebo while hospitalized, followed by continued outpatient therapy, every 2 to 4 weeks, for up to 6 months. * Participants will remain on the assigned regimen for 6 months or until they have experienced new onset of severe adverse event on one occasion within 24 hours of study medication that are related to the study drug, whichever comes first. At that time, the participant will be discontinued from drug administration.