What is blood (serum) allergy testing?
Blood allergy testing is usually reserved for those cases in which skin testing cannot be performed. This scenario occurs when an animal cannot be sedated due to another medical reason or when appropriate drug (eg, steroids) withdrawal cannot be accomplished. Most dermatologist would agree that skin testing gives a better reflection of what the skin is reacting to compared to blood testing alone. Many times skin testing and blood allergy testing are used together to get a better overall assessment of which allergens are bothersome to the pet. It is important that other causes of pruritus (itch) have been excluded before performing and interpreting the blood allergy test alone, specifically in nonseasonal allergic individuals.
This test involves drawing a blood sample and sending to a laboratory for evaluation for environmental allergies. Although technically this is much easier to perform, most dermatologists feel that the results of blood allergy testing are less accurate than allergy skin testing. This test is usually reserved for those cases in which it is not possible to perform an allergy skin test. This situation occurs when sedation or drug withdrawal is not possible. Occasionally, both skin testing and blood testing will be recommended to more accurately assess an individual patient.
