A Review of Food Challenges Performed on Children with Large Skin Prick Tests
Sunday, March 6, 2016
South Exhibit Hall H (Convention Center)
Malika Gupta, MD, Liron D. Grossmann, MD, Jonathan M. Spergel, MD PhD FAAAAI, Antonella Cianferoni, MD PhD FAAAAI
Rationale: Food allergy diagnosis is based on history, measurement of specific IgE by either serum IgE or skin prick tests (SPTs) and oral food challenges (OFCs). Large SPT wheal sizes (≥ 10mm) are associated with high rate of failed OFCs, and physician reluctance to perform OFCs. 

Methods: We examined OFC outcomes in children with SPTs ≥ 10 mm wheal size. The clinical characteristics of those who passed OFCs were compared with those who failed within this group. 

Results: Out of 2304 children who underwent OFCs, 328 (14%) had SPTs ≥ 10 mm. Within this group, 66% failed OFCs, and 26% were treated with epinephrine.  Failure rate varied for different food antigens with the majority of children undergoing OFCs for peanut, milk, egg, tree nuts failing (82%, 71%, 70%, 67%respectively), and the majority of children undergoing OFCs to meats, baked egg, baked milk and seeds  passing (78%, 75%, 67%, 60% respectively). Higher rate of epinephrine use was observed in OFCs to tree nuts, peanuts and seeds (46%, 40% and 36% respectively), and lower in  OFCs to baked egg, baked milk, milk, meat and egg (5%, 16%, 18%,22% and 23% respectively). 

Conclusions: Large SPTs are associated with a high rate of failed OFCs with a significant portion of these children receiving epinephrine, especially for tree nuts and peanuts.  However, several other food antigens have a high pass rate with low use of epinephrine despite a large SPT.  Thus, performance of supervised OFCs can be considered in certain situations despite large SPTs to avoid unnecessary restrictive diets.