IgE
What it measures, and what changes the number.
Immunoglobulin E (IgE) is the antibody class involved in allergic reactions and in the response to some parasites. It circulates in very small amounts compared with other antibodies. This test measures total IgE in serum, meaning all IgE regardless of what it targets.
It is often read alongside allergen screens such as Phadiatop, allergen-specific IgE tests, eosinophil counts and eosinophil cationic protein, since these together describe allergic and eosinophil activity. It may also be included with other immunoglobulins such as IgG and IgA.
Total IgE is measured by immunoassay and does not usually require fasting. Expected values depend strongly on age and differ between assay platforms, and results may be expressed in kU/L or IU/mL. Total IgE is a different test from specific IgE to a single allergen. Labs may print it as IgE, Total IgE, Immunoglobulin E or Inmunoglobulina E.
Often read alongside: Phadiatop (inhalant screen), Eosinophils, Eosinophils %, Eosinophil cationic protein (ECP), IgG