Published Online: June 30, 2016
Oral food challenges are undertaken to determine whether a patient is truly allergic to a food. They can be used when allergy history and/or testing are not definitive, or when testing indicates a patient may have outgrown a food allergy. The challenge typically starts with a small amount of the food that is increased over several steps while monitoring for reactions. While this approach is often considered the gold standard for confirming food allergy, it is time and resource-intensive and poses a risk of anaphylaxis. While skin and blood testing can help predict which patients are likely to tolerate a food, they are not always diagnostic.
In a study published online in The Journal of Allergy and Clinical Immunology: in Practice, Andrew MacGinnitie and colleagues from Boston Children’s Hospital utilized a novel quality improvement initiative to make oral food challenges safer. Using a Standardized Clinical Assessment and Management Program (SCAMP), they stratified patients into low- and high-risk groups based on history of reactions, blood and skin testing and other criteria. High-risk challenges were undertaken in the hospital infusion center and used up to seven incremental steps. Lower-risk challenges were done in the allergy clinic using three steps. Clinicians could change these assignments if they documented their reasoning. The challenge results were then analyzed and the criteria iteratively improved.
The results of more than 1,000 challenges, involving a variety of foods, showed that while 10-20% of patients failed challenges, patients at risk of anaphylaxis were appropriately triaged to the infusion center. Only 1% of patients challenged in the clinic setting required epinephrine injections for a failed challenge, versus 5% of those in the infusion center. Asthma, even intermittent asthma not requiring daily treatment, emerged as a predictor of severe reactions. Over time, the SCAMP criteria were revised, allowing a higher proportion of challenges to be done safely in the clinic with an abbreviated challenge procedure, while identifying patients needing to be challenged more gradually with closer nursing supervision.
The authors concluded that individuals at high risk of severe reactions during food challenge could be prospectively identified, allowing those at lower risk to undergo modified challenges. Overall, more than 80% of patients passed their challenge and were able to reincorporate the challenged food into their diet.
The Journal of Allergy and Clinical Immunology: In Practice is an official journal of the AAAAI, focusing on practical information for the practicing clinician.