A month or so ago, I was lucky enough to participate in an online peanut allergy summit to learn more about the UKnowPeanut test for those with peanut allergies. I learned a lot and have been anxious to share, but wanted to you to hear about the testing straight from the source…enter Dr. Reinhardt, Medical Director of the ImmunoDiagnostics business of Thermo Fisher Scientific.
Dr. Reinhardt was kind enough to do a guest post here on The Food Allergy Mom, so you can learn more about this new molecular allergy test and what it means for individuals with peanut allergies.
A special thanks to Michelle and Dr. Reinhardt at Isitallergy for collaborating to make this information accessible to so many food allergy families!
Check back soon for a similar post from Dr. O’Connor, also a participant in the online peanut allergy summit!
“I’m Dr. Rob Reinhardt, Medical Director of the ImmunoDiagnostics business of Thermo Fisher Scientific and blogger at Is It Allergy. We recently hosted an online peanut allergy summit and I was happy to be offered the chance to write a guest post providing The Food Allergy Mom’s readers with more information about peanut allergy diagnosis and advances in testing technology.
Specifically, I’d like to talk about our new molecular allergy test, uKnow Peanut, an important new diagnostic tool that can help families dealing with suspected peanut allergy to better understand its risk and severity.
The uKnow Peanut test is the first simple blood test that can help predict the likelihood of a systemic reaction. It is a package of component tests, carefully selected to evaluate peanut IgE sensitization patterns at the molecular level. To understand how molecular allergy (or component) testing technology for peanut works, it’s important to first examine the makeup of the peanut.
Traditional allergy tests look for sensitization to the whole peanut. But with molecular testing, we can drill down to pinpoint a patient’s sensitivity to individual molecules within the peanut. This is important because a patient’s level of risk of reaction is directly correlated to the molecule(s) he or she is sensitized to. With this new technology, we can now diagnose and predict with greater certainty, the true risk of reaction for a patient with peanut allergy.
There are currently five allergen component tests cleared by the FDA. Three of the allergen components (Ara h 1, Ara h 2 and Ara h 3) are connected with a high risk of eliciting systemic reactions. In other words, sensitization to these proteins can help predict the likelihood of a severe reaction from exposure to peanut. Another component, Ara h 9 might give rise to systemic reactions.
Ara h 8 belongs to the family of proteins that mainly give rise to milder, localized reactions such as oral allergy syndrome (OAS). 99% of patients sensitized to Ara h 8 alone passed an oral food challenge at the highest dose or had already consumed peanuts without a reaction.
A recent clinical study determined that only one in four children sensitized to whole peanut have a high risk of severe reaction. So component testing means more clarity and perhaps a significant improvement in quality of life for families with children who have been diagnosed. The data from the study indicates that roughly 80 percent of children who are sensitized to peanut are not clinically allergic and may not be at risk for a severe reaction.
Knowing which protein(s) your child is sensitized to can make a big difference. As an example, Dr. Maeve O’Connor, an allergist from Charlotte, NC, shared a case study of her patient, “Margaret,” a 6 year old who tested positive for peanut allergy using traditional blood and skin prick testing. However, a recent episode where she accidentally ingested a granola bar with peanut – without incident – confused her parents.
Dr. O’Connor ordered a uKnow Peanut test and determined that Margaret was positive for Ara h 8, the protein that gives rise to local reactions and negative to those proteins associated with severe reactions. Armed with this information, Dr. O’Connor conducted a food challenge test and Margaret passed.
Margaret was one of the roughly 80 percent of children who are sensitized to peanut and are not clinically allergic, meaning they may not be at risk for a severe reaction. As a result of molecular allergy testing and as confirmed by the food challenge, she no longer has to sit at the peanut free table in the school cafeteria, and her parents can breathe easier knowing her true risk of reaction.
Dr. O’Connor tested another patient, “Thomas,” a 16 year old boy, who had a severe reaction to peanut at a young age and both skin tests and traditional blood tests were previously positive to peanut. His parents implemented a strict nut‐free diet, but as he got older, Thomas was not careful when his parents weren’t around, rarely carrying his epinephrine auto‐injector. The uKnow Peanut test showed high sensitivity to Ara h 2 and Ara h 8, indicating that Thomas is at risk for severe reactions. The positive test findings confirmed his sensitivity to a component highly associated with a severe reaction to peanut. He now understands the importance of carrying his epinephrine auto‐injector and alerting coaches and friends about the serious risks associated with his allergy.
Every child is different, and so are their peanut allergies. Our hope in educating the online community about peanut component testing is that we can help other families with peanut allergic kids to gain a more complete understanding about the nature of their children’s allergies. And remember, it is important to review uKnow Peanut or any test results comprehensively with your doctor to get the full picture of your child’s level of risk.
For any readers who want to learn more about molecular allergy testing, I encourage you to visit our blog, www.isitallergyblog.com, and connect with us on Facebook or Twitter @isitallergy. Please also feel free to direct any specific questions via email to: firstname.lastname@example.org
 Nicolaou et al. J Allergy Clin Immunol. 2010;125:191-197 2. Dang et al. J Allergy Clin Immunol. 2012;129:1056-1063.