Outcomes and factors associated with tolerance in infants with non-IgE-mediated cow's milk allergy with gastrointestinal manifestations

Abstract Objectives To evaluate outcomes of oral food challenge (OFC) test to assess tolerance in infants with non-IgE-mediated cow's milk allergy (CMA) with gastrointestinal manifestations and explore clinical data predictive of these outcomes. Methods Single-center retrospective study including infants (age < 12 months) who were referred for CMA between 2000 and 2018 and underwent OFC on follow-up. A univariate logistic regression test was performed to evaluate variables associated with the outcomes of the follow-up OFC test. Results Eighty-two patients were included, 50% were male. Eighteen patients had a positive OFC test (22%). Most patients had presented with hematochezia (77%). The median age of symptom onset was 30 days. Two-thirds of the patients were on appropriate infant formula (extensively hydrolyzed or amino acid-based formula), exclusively or in association with breastfeeding. The median time on an elimination diet before the OFC test was 8 months (Q1 6 - Q3 11 months). All cases with positive follow-up OFC tests (n= 18) had been exposed to cow's milk-based formula before the first clinical manifestation of CMA. Five out of eight cases with Food Protein-Induced Enterocolitis Syndrome (FPIES) had positive OFC tests. Exposure to cow's milk-based formula before diagnosis, a history of other food allergies, hematochezia and diarrhea were predictors of a positive OFC test. Conclusions In infants with non-IgE-mediated CMPA with gastrointestinal manifestations, the use of cow's milk-based formula, a history of other food allergies, and hematochezia and diarrhea upon initial presentation were associated factors for the later achievement of tolerance.

Proctocolite induzida por proteína alimentar - teste de provocação oral deve ser realizado para confirmar o diagnóstico de alergia ao leite de vaca em neonatos? / Induced proctocolitis - oral food challenge should be done to confirm the diagnosis of cow's milk allergy in neonates?

ABSTRACT Background: Suspicion of food protein-induced proctocolitis based on empirical understanding of rectal bleeding can lead to misdiagnosis. Objective: to verify clinical and evaluative characteristics of patients who presented neonatal rectal bleeding and were on a restricted cow's milk diet. Methods: A cross-sectional retrospective study included patients followed up in a tertiary care center, who presented rectal bleeding in the neonatal period. The analyzed data included gender, gestational age, type of delivery, use of antibiotics during the last trimester of pregnancy, use of parenteral nutrition before the first manifestation, use of mechanical ventilation, initial clinical manifestations associated with rectal bleeding, diet before the first manifestation, period of elimination diet, oral food challenge (OFC) results and symptoms presented in cases of positive OFC. Fisher's exact test and Mann-Whitney test were used to analyze the data. The level of significance was set to 5%. Results: Forty-two patients were selected: 30 preterm infants, 34 cesarean deliveries, 10 exclusively breastfed patients before rectal bleeding. Median age at OFC was 6.3 months old. Median of length of the elimination period before OFC was 5.9 months. OFC was negative in 33/42 (79%) patients and positive in 9/42 (21%). There was no association between OFC results and the evaluated data. The main symptom observed in patients with positive OFC was blood in stools. Conclusion: OFC was negative in most cases of suspected cow's milk allergy due to rectal bleeding in neonates, most of them with a history of prematurity.

RESUMO Contexto: A suspeita de proctocolite induzida por proteína alimentar (PCIPA) com base na compreensão empírica de sangramento retal pode levar a diagnósticos equivocados. Objetivo Verificar as características clínicas e evolutivas de pacientes que apresentavam sangramento retal neonatal e faziam uso de dieta restrita com leite de vaca. Métodos: Estudo transversal retrospectivo com pacientes acompanhados em um centro terciário, que apresentaram sangramento retal no período neonatal. Os dados analisados incluíram: sexo, idade gestacional, tipo de parto, uso de antibióticos no último trimestre da gravidez, uso de nutrição parenteral antes da primeira manifestação, uso de ventilação mecânica, manifestações clínicas iniciais associadas ao sangramento retal, dieta antes da primeira manifestação, período de dieta de eliminação, resultados do teste de provocação oral (TPO) e sintomas apresentados em casos de TPO positivo. O teste exato de Fisher e o teste de Mann-Whitney foram usados para analisar os dados. O nível de significância adotado foi de 5%. Resultados: Quarenta e dois pacientes foram selecionados: 30 prematuros, 34 partos cesáreos, 10 pacientes amamentadas exclusivamente antes do sangramento retal. A idade média na ocasião do TPO foi de 6,3 meses. A mediana da duração do período da dieta de eliminação antes do TPO foi de 5,9 meses. O TPO foi negativo em 33/42 (79%) pacientes e positivo em 9/42 (21%). Não houve associação entre os resultados do TPO e os dados avaliados. O principal sintoma observado em pacientes com TPO positivo foi sangue nas fezes. Conclusão: O TPO foi negativo na maioria dos casos de suspeita de alergia ao leite de vaca devido a sangramento retal em neonatos, a maioria deles com história de prematuridade.