Risk Factors Influencing Tolerance and Clinical Features of Food Protein-Induced Allergic Proctocolitis

This multi-center study sought to describe the clinical features and natural course of disease in a large group of 257 infants with food protein induced allergic proctocolitis (FPIAP) with assessment of risk factors for persistence of disease.

Two hundred and fifty-seven infants diagnosed with FPIAP between 2014 and 2017 in 5 different allergy or gastroenterology outpatient clinics were included in this study.

Infants who were admitted with rectal bleeding and had a diagnosis of FPIAP were enrolled. Age, sex, time of onset and type of symptoms, causative food(s), concomitant diseases, physical evaluation results, skin prick testing results and laboratory findings (total IgE, food-specific IgE levels, eosinophil and neutrophil counts), treatment, and family history of allergic diseases were evaluated. Antibiotic use was assessed through medical record review. Food triggers were evaluated through elimination-reintroduction trials. Risk factors for persistent course were determined by logistic regression analyses.

Of 257 patients, 50.2% (n = 129) were girls. At diagnosis, 97.2% were breast-fed and 66.5% were exclusively breast-fed. Median duration of breast-feeding was 13 (IQR 6.5–18) months. The most common trigger was cow’s milk (99.2%). Twenty-four percent of the patients had multiple food allergies, and these children had more common antibiotic use (41.9% vs 11.8%), atopic dermatitis (21% vs 10.2%), wheezing (11.3% vs 1.5%), colic (33.8% vs 11.2%), and IgE sensitization (50% vs 13.5%) as compared with the single-food allergy group (P < .001, P = .025, P = .003, P < .001, respectively). The presence of colic (odds ratio [OR]: 5.128, 95% CI: 1.926–13.655, P = .001), IgE sensitization (OR: 3.964, 95% CI: 1.424–11.034, P = .008), and having allergy to multiple foods (OR: 3.679, 95% CI: 1.278–10.593, P = .001) were found to be risk factors for persistent disease after 1 year of age.

Infants with FPIAP and colic, IgE sensitization, or allergy to multiple foods should be followed more closely, with extended follow up due to the likelihood their disease will persist beyond one year of age.

There is a paucity of literature with primary data on the natural history of FPIAP, food triggers, and natural history of disease. This study comprehensively evaluates the symptoms, food triggers and IgE sensitization to food in a large number of patients. Risk factors for late tolerance have not been depicted in such a large group of FPIAP patients before. Given the relatively common proportion of children with FPIAP with multiple food allergies (24%) and IgE sensitization (23%), evaluating IgE in infants with FPIAP would be useful to help identify the infants with a more prolonged clinical course. It is also helpful to understand that in addition to cow’s milk, other food triggers for these infants include egg, tree nuts, wheat peanut, sesame, soy and corn. Elimination and reintroduction diets may be helpful in infants with FPIAP who have residual symptoms after cow’s milk elimination.