How is ige measured

But it does not reveal what you are allergic to. A specific IgE test will help identify your particular allergy. If your results indicate an allergy, your health care provider may refer you to an allergy specialist or recommend a treatment plan. Your treatment plan will depend on the type and severity of your allergy. People at risk for anaphylactic shock, a severe allergic reaction that can cause death, need to take extra care to avoid the allergy-causing substance.

They may need to carry an emergency epinephrine treatment with them at all times. Learn more about laboratory tests, reference ranges, and understanding results. An IgE skin test is another way to detect allergies, by measuring IgE levels and looking for a reaction directly on the skin. Your health care provider may order an IgE skin test instead of, or in addition to, an IgE allergy blood test.

The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. Allergy Blood Test. What is an allergy blood test? What is it used for? Why do I need an allergy blood test? What happens during an allergy blood test? Will I need to do anything to prepare for the test? You don't need any special preparations for an allergy blood test.

If you have questions about the allergen-specific IgE test or what the test results mean, talk to your doctor. Reviewed by: Larissa Hirsch, MD. Larger text size Large text size Regular text size. What Is a Blood Test? What if I Have Questions? Evaluation of patients with suspected diseases associated with elevations in total immunoglobulin E IgE , including allergic disease, primary immunodeficiencies, infections, malignancies, or other inflammatory diseases.

Immunoglobulin E IgE is one of the 5 classes of immunoglobulins and is defined by the presence of the epsilon heavy chain. It is the most recently described immunoglobulin, having first been identified in IgE exists as a monomer and is present in circulation at very low concentrations, approximately fold lower than that of IgG.

The physiologic role of IgE is not well characterized, although it is thought to be involved in defense against parasites, specifically helminthes. The function of IgE is also distinct from other immunoglobulins in that it induces activation of mast cells and basophils through the cell-surface receptor Fc epsilon RI.

Fc epsilon RI is a high-affinity receptor specific for IgE that is present at a high density on tissue-resident mast cells and basophils. Because of this high-affinity interaction, almost all IgE produced by B cells is bound to mast cells or basophils, which explains the low concentration present in circulation. Cross-linking of the Fc epsilon RI-bound IgE leads to cellular activation, resulting in immediate release of preformed granular components histamine and tryptase and subsequent production of lipid mediators prostaglandins and leukotrienes and cytokines interleukin-4 and interleukin Elevated concentrations of IgE are generally thought of in the context of allergic disease.

However, increases in the amount of circulating total serum IgE can also be found in various other diseases, including primary immunodeficiencies, infections, inflammatory diseases, and malignancies.