PURPOSE OF THE STUDY.
To determine the utility of food allergy panel testing among patients referred to a pediatric food allergy center.
New patients seen between September 2011 and December 2012 by 1 provider in a tertiary referral pediatric food allergy center at Southwestern Medical Center in Dallas, Texas.
This was a retrospective chart review. An analysis was performed to calculate the estimated cost of evaluation for patients who have received a food allergy panel.
Of 797 new patient encounters, 284 (35%) patients had received a food allergy panel. Only 90 (32.8%) patients had a history warranting evaluation for food allergy; 126 were avoiding a food on the basis of recommendations from the referring provider, and 112 (88.9%) were able to reintroduce at least 1 food into their diet. The positive predictive value of food allergy panel testing in this unselected population was 2.2%. The estimated cost of evaluation for this population was $79 412.
Food allergy panel testing often results in misdiagnosis of food allergy, overly restrictive dietary avoidance, and an unnecessary economic burden on the health system.
This clinical concept cannot be stressed enough! It is an important issue that comes up time and time again and needs to be appropriately understood. The results showed that panels of food-specific immunoglobulin (Ig)E testing have little utility as a screening tool. Misdiagnosis of food allergy is partially due to the low positive predictive values of IgE tests. Another reason for the misdiagnosis of IgE-mediated food allergy from these tests is a lack of understanding about what is a true food allergy, a specific immune response that occurs with a given food allergen. Testing should be guided by the clinical history and limited to the food(s) in question. The misdiagnosis of food allergy can lead to multiple consequences, including social consequences and nutritional deficiencies from inappropriate food restriction. Comprehensive evaluations consider the history in context of food allergy immunopathogenesis and epidemiology, select tests on these factors, and interpret them in context. Additional tests may include skin tests and physician-supervised oral food challenges. The concepts addressed in this investigation cannot be overemphasized, especially to busy general pediatricians who are bombarded with this type of testing data in their offices.
- Copyright © 2015 by the American Academy of Pediatrics