Oral Food Challenges: “Undiagnosing” Food Allergies

The idea of eating a food that you’ve avoided your whole life because you have been allergic must be incredibly frightening. However, a recent article outlined the value of doing just this in a supervised clinical environment. Called an oral food challenge, patients that qualify are fed a tiny amount of their allergen over a specific time frame with the goal of eating an entire serving of the food without having a reaction. Those who can do that are no longer considered allergic. Oral food challenges are considered the gold standard for diagnosing a food allergy, but they’re also essential to “undiagnosing” a food allergy – or determining if the individual has outgrown the food allergy.

 

Many in the food allergy community, patients, families and clinicians, are concerned about the safety of an oral food challenge.  Researchers Kwei Akuete, et al. aimed to determine the prevalence of anaphylaxis in clinic-based oral food challenges across five food allergy centers between 2008 and 2013. There were 6,377 oral food challenges conducted during that time with anaphylaxis occurring 2% of the time. Epinephrine was administered 1% of the time overall for the total number of oral food challenges performed. The total rate of reactions was just 14%, meaning that 86% of participants passed their oral food challenge and were no longer considered allergic to their allergen.

 

In this study, most of the participants were considered low-risk, because they either had not had a reaction recently, were tolerant to ingestion, or had low levels of specific IgE unless cross-sensitization was suspected. According to the authors, the allergists office is the best place to conduct oral food challenges, because they are trained to manage anaphylaxis. Moreover, they state, “Allergists should perform this practice on a regular basis to ensure patients do not needlessly avoid foods for fear of allergic reactions and thus subsequently live with the anxiety related to avoidance.”

 

The study had multiple limitations such as the inability to collect “more robust data” because of changes in the way record were kept, determination of biphasic reactions (where a reaction occurs, is treated, and the reoccurs some time later), and to determine a complete picture of all food allergies. In addition, all of the sites involved were tertiary research sites with abundant resources. Also, there was not good differentiation between IgE-mediated and non-IgE-mediated food allergies in the study population as well as differences in the way that oral food challenges were recommended to patients.

 

Researchers determined that oral food challenges are safe and that allergists should perform them when indicated. Oral food challenges should not be conducted at home or without medical supervision. Patients and parents of allergic children should always discuss their questions, concerns, and plan of care with their healthcare provider.

 

Reference:
Akuete K, Guffey D, Israelsen R., et al. Multicenter prevalence of anaphylaxis in clinic-based oral food challenges. Ann Allergy Asthma Immunol. 2017:1-10.