An IgE Blood Test is used to evaluate immunoglobulin status in possible atopic disease. Atopic disease indicates a predisposition toward the development of certain allergic reactions such as hay fever (allergic rhinitis), asthma, eczema (atopic dermatitis), food allergies and other conditions.
No fasting is required for the Immunoglobulin E blood test from Walk-In Lab, and results are typically delivered in two to three days.
In normal individuals, the concentration of IgE in serum typically represents <0.001 percent of total immunoglobulins present. When sensitive individuals are exposed to allergens, IgE class immunoglobulins are important in mediating the atopic reactions that occur. IgE consists of four chains: two light chains and two heavy chains. This structure is similar to other immunoglobulins. Each of the IgE molecule’s heavy chains contain a variable region that accounts for antigen specificity. IgE myeloma is extremely rare, therefore the clinical utility of measuring IgE levels typically involves mediating the allergic response. Most IgE molecules in serum are bound to the surface of basophilic granulocytes and mast cells. The interaction of allergens with the cell-bound allergen-specific IgE can cause these cells to initiate an allergic reaction by releasing histamines and other vasoactive substances.
Approximately half of individuals with allergic rhinitis or asthma have elevated levels of IgE. A large number of individuals with allergies and elevated levels of IgE to specific allergens will have normal levels of total IgE however. Some studies indicate that total IgE levels can be elevated in patients with atopic dermatitis and the concentration of IgE can correlate with the severity of eczema. Patients with parasitic infections, immunodeficiency or allergic bronchopulmonary aspergillosis may also have elevated levels of total IgE.