: Egg Yolk Basophil-Binding Antibody, Qualitative

: What This Test Measures

: The test looks for antibodies in the blood that bind to basophils after exposure to egg yolk material. Basophils are a type of white blood cell involved in allergic responses; binding of antibodies to these cells is one way laboratories assess sensitization to a specific allergen.

: Why It May Be Ordered

: A healthcare provider may order this test when evaluating a possible allergy to egg yolk, especially when skin or other antibody tests are inconclusive or when symptoms suggest a reaction. It is generally ordered alongside a careful history of exposure and symptoms.

: How the Test Is Performed

: A blood sample is collected from a vein, usually in the arm, and sent to a specialized laboratory. The laboratory incubates the sample with egg yolk proteins and measures whether antibodies bind to basophils, reporting a qualitative result.

: What Results Mean

: A positive result suggests antibodies against egg yolk proteins are present, which may indicate sensitization, but it does not by itself diagnose an allergy. A negative result makes sensitization less likely but must be considered with symptoms, timing of exposure, and other test findings.