Rectal Bleeding and Cow’s Milk Protein-induced Allergic Proctocolitis: A Prospective Study

Abstract

To assess time to resolution of food protein–induced allergic proctocolitis (FPIAP).In this study, researchers evaluated 76 infants aged <4 months with rectal bleeding (RB) referred to the pediatric gastrointestinal department at Trousseau Hospital in Paris, France, between May 2014 and December 2017. Only infants whose RB responded to a cow’s milk elimination diet were included in the study.This was a prospective cohort of infants with concern for cow’s milk protein (CMP) allergy who had resolution of RB with CMP elimination. Exclusion criteria included RB because of another etiology and exclusively breastfed infants. A total of 2 to 8 weeks after resolution of RB, CMP oral food challenge (OFC) was completed. If FPIAP was confirmed, OFC was repeated every 2 months after the age of 4 months to assess the time to tolerance of CMP. Ongoing FPIAP CMP was defined as RB, behavioral change, diarrhea, and vomiting. Tolerance was defined as CMP daily without symptoms.Only 31% of the cohort failed OFC at initial diagnostic challenge, meaning that over two-thirds of infants who initially responded to CMP exclusion did not have return of symptoms on rechallenge just weeks later. Of the patients confirmed to have FPIAP CMP, the median age of tolerance was determined to be 6.8 months, with >75% of the cohort tolerant by 10 months. Infants with a first-degree family history of atopic disease developed tolerance later (8.9 months versus 5.1 months).In this work, it was confirmed that the majority of RB in infants is likely not related to FPIAP CMP. This study also revealed that the time to resolution might be earlier than previously thought.Although there are no solid guidelines on introduction of CMP in presumed FPIAP CMP, the majority of patients exclude CMP until approximately 1 year. In this study, it was found that only one-third of RB before 4 months was due to FPIAP. Of those with FPIAP, CMP could be challenged earlier and at more frequent intervals depending on family wishes. A major limitation of this study is that exclusively breastfed infants were excluded and the lack of information on maternal diet in those who were nursing.