* Abbreviations: CI — : confidence interval FPIAP — : food protein-induced allergic proctocolitis IgE-FA — : immunoglobulin E–mediated food allergy OR — : odds ratio Immunoglobulin E–mediated food allergy (IgE-FA) can be life-threatening in children, and rates are rising in the United States.1 We now know that early introduction of allergenic foods can reduce the risk of IgE-FA.2 Food protein-induced allergic proctocolitis (FPIAP) (also called cow’s milk protein allergy and/or intolerance or non–IgE-mediated milk allergy) is an early, common form of food allergy presenting with bloody or mucoid stools, often together with fussiness and feeding difficulty.3,4 Not thought to be associated with IgE-FA, … Address correspondence to Qian Yuan, MD, PhD, MassGeneral for Children, Massachusetts General Hospital, 55 Fruit St, CPZS 553, Boston, MA 02114. E-mail: qyuan{at}mgh.harvard.edu