Casein

Casein is the main protein found in cow's milk, accounting for approximately 80% of its total protein content. In some individuals, the immune system mistakenly recognizes casein as an allergen, which may lead to the development of IgE-mediated allergic reactions.

Measurement of casein-specific IgE antibodies helps confirm sensitization to this protein, assess the risk of allergic reactions, and differentiate cow's milk allergy from other conditions, such as lactose intolerance.

Indications

The test is recommended for individuals with:

• skin redness, itching, or rash after consuming milk or dairy products;
• hives (urticaria);
• swelling of the lips, tongue, mouth, or throat;
• abdominal pain, nausea, vomiting, or diarrhea after consuming dairy products;
• cough, wheezing, or difficulty breathing after drinking milk;
• suspected allergy to cow's milk proteins;
• the need to identify the cause of allergic reactions;
• follow-up of patients with a confirmed milk allergy.

How does the allergic reaction develop?

In allergic individuals, the immune system mistakenly recognizes casein as a harmful substance and produces specific IgE antibodies. Upon subsequent exposure to the allergen, histamine and other biologically active substances are released, leading to symptoms such as itching, skin rash, swelling, digestive disturbances, cough, difficulty breathing, and other allergic manifestations.

Measuring casein-specific IgE helps confirm IgE-mediated allergic sensitization and assess the likelihood of allergic reactions following the consumption of milk and products containing casein.

Procedure

The test is performed using a venous blood sample.

The sample is analyzed in the laboratory to determine the level of casein-specific IgE antibodies. The test is safe because it does not require direct exposure to the allergen.