The information in this website is intended only for healthcare professionals. By entering this site, you are confirming that you are a healthcare professional.
There are two types of specific IgE blood tests: Whole allergen and allergen components. A whole allergen blood test shows what type of allergen the patient is sensitized to, while an allergen component test can determine—down to the molecular level—what components (proteins) could be causing your reaction.
Whole allergen testing is used to confirm a suspected allergy, to determine your allergic triggers, or to even rule out an allergy all together.1-3 A simple blood test can reveal potential sensitization to hundreds of possible allergens with one blood sample. It can identify specific regional allergens and hundreds of food allergens as well. For instance, if you are experiencing symptoms at home and assume they are caused by a family pet, a blood test might reveal the true cause as dust mites. Whole allergen and component allergen test results can help provide accurate information on whether or not you are still sensitized to those allergens. Knowing the cause can ease stress when it comes to managing your symptoms.
Allergen component testing can help pinpoint the allergenic proteins causing the symptoms4 and bring peace of mind to someone who’s not sure what the primary cause of their symptoms is.
Allergen components can help:
1. Assess the risk for reaction – mild to severe (like anaphylaxis)
2. Explain symptoms due to cross-reactivity
3. Improve diagnostic accuracy
Each allergen source (what’s identified through whole allergen testing) contains one or more allergenic proteins. This information is important for your healthcare professional to improve your management plan.
For example, a positive component test result to specific peanut proteins helps identify that peanut is most likely the cause of your symptoms. This may also indicate that you are at risk for a systemic reaction (anaphylaxis), if peanuts are consumed.
Another example is when a child is allergic to milk or egg. In these cases a positive component test result to certain specific proteins indicates the child is most likely not to tolerate these foods, even if baked. However, if the test result is negative to these specific proteins, the child may tolerate milk and egg if baked, e.g. cake or cookies.
Cross-reactive proteins are more widely distributed and may be shared between a very wide range of allergen sources. Since they are similar in their structure, they may cause a cross-reactive allergic reaction. A good example is someone with a primary allergy to birch pollen. This may trigger a mild and localized peanut reaction because one of the peanut proteins is structurally similar to the protein in birch pollen and a cross-reaction may occur.
Component testing will help your healthcare professional identify what proteins are causing your reactions, which can make allergy management easier. So, instead of assuming you are allergic to peanuts, component testing may help to distinguish between a severe clinical allergy, as opposed to a milder cross-reaction.
By revealing your precise allergies, and testing for your unique proteins, blood testing may be able to help diagnose, and optimize your allergy management.