There is no current cure for peanut allergy. Accidental exposures are common and can be severe. To assess children who had severe reactions during oral peanut challenges, scientists identified certain biomarkers that would help them see who would be at higher risk with accidental ingestion of 0.1 gram of peanut protein (about half a peanut kernel).
Ways to identify peanut allergy at an allergists office are skin prick testing to peanuts as well as peanut IgE testing with components.
Ara h 2 is a discriminative marker to diagnose peanut allergy and as association with severity has been observed. Other tests that were studied were the basophil activation test (BAT) and ratio of IgG4/IgE to peanut. For the purposes of this blog we will only discuss the skin prick and IgE testing as this is what is most commonly used by allergists.
The probability of severe or life-threatening reactions to peanut showed in children those who had:
- Skin prick test to peanut greater than 8 mm
- Ara h 2-specific IgE greater than 1.4 KU/L
The patients identified are at risk of reacting to a low dose of the peanut and/or at risk of developing life-threatening reactions.
There is currently 1 FDA approved treatment for peanut allergy and another one currently in development.
For all patients who have peanut allergy including those who use Palforzia, they still need to continue to avoid all peanut products. Using the biomarkers identified above, this could help identify patients who are at highest risk for the most severe reactions after accidentally ingesting even a small amount of peanut. Nevertheless, all patients need to be vigilant and continue to read labels and avoid peanuts. An epinephrine auto-injector is a life-saving device that should be carried at all times in case of an anaphylactic reaction.