Measurement of serum levels of which immunoglobulin is used as a screening test for multiple allergies?

The measurement of serum levels of IgE is crucial in screening for multiple allergies. IgE is a type of antibody that plays a significant role in the allergic response. When an individual is exposed to an allergen, the immune system may produce IgE antibodies specific to that allergen. Elevated levels of IgE in the serum can indicate an individual's sensitization to various allergens, making it an effective biomarker for allergic conditions such as asthma, hay fever, and food allergies.

IgE's involvement in allergic reactions occurs when it binds to allergens and triggers mast cells and basophils to release histamines and other mediators, leading to allergy symptoms. This immediate hypersensitivity reaction is a hallmark of allergy testing. Therefore, testing for elevated serum IgE levels is a standard approach to assessing and diagnosing allergies in patients.

In contrast, IgG is mainly associated with the responses to infections and long-term immunity, IgA is primarily found in mucosal areas and secretions, and IgM is the first antibody produced in response to an infection. While these immunoglobulins serve essential functions in the immune system, they are not typically used as screening tests for allergies. This specificity of IgE for allergic responses is why it is the correct choice in this