Casein (f78) IgE

Casein (f78) IgE - This test is an allergen-specific IgE antibody test that quantifies an individual's IgE response to casein. It is an in vitro quantitative assay, which is intended to be used in conjunction with other clinical information to aid in the diagnosis of food allergy [1].

While allergen-specific serum IgE testing is considered comparable to skin testing in many instances, both the American Academy of Allergy, Asthma, and Immunology and the American College of Allergy, Asthma, and Immunology recognize that allergen-specific serum IgE testing may be preferred in some clinical situations. These include 1) the presence of widespread skin disease, 2) the recent use of antihistamines or other medications that can affect the results of allergy skin tests, 3) uncooperative patients, and 4) medical history suggesting that allergen skin testing would pose a significant risk for a serious allergic reaction [1].

Food-specific IgE tests are extremely sensitive. However, a positive test result only indicates that a patient is IgE sensitized to the food of concern. Many IgE-sensitized patients do not develop any symptoms when this food is ingested. A diagnosis of food allergy should only be made by a trained medical provider, after conducting a thorough clinical evaluation [2,3]. While food-specific IgE test results may contribute to that evaluation, they cannot replace it. In this regard, detection of food-specific IgE in serum provides evidence of IgE sensitization, but a history of clinical reactivity to the food of concern, is required to make a diagnosis of IgE-mediated food allergy. Moreover, several forms of food hypersensitivity are not associated with the presence of food-specific IgE in serum.

More specific information about this allergen can be found at http://www.phadia.com/en/Products/Allergy-testing-products/ImmunoCAP-Allergen-Information/Food-of-Animal-Origin/Allergen-Components/nBos-d-8-Casein-Milk/

1. Bernstein IL, et al. Ann Allergy Asthma Immunol. 2008;100(suppl 3):S1-S148.
2. Sampson HA, et al. J Allergy Clin Immunol. 2014;134(5):1016-1025.
3. Boyce JA, et al. J Allergy Clin Immunol. 2010;126(6 suppl):S1-S58.

• Preferred Specimen(s): 0.3 mL serum 
• Alternative: NA 
• Minimum Volume: 0.15 mL 
• Collection Instructions: NA 

• Transport Container: Serum separator tube (SST) 
• Transport Temperature: Room Temperature 
• Specimen Stability: 
• Room temperature: 14 days 
• Refrigerated: 14 days 
• Frozen: 30 days 
• Reject Criteria: NA