The Natural Course of Adult-Onset Food Protein-Induced Enterocolitis Syndrome.

BACKGROUND: Adult-onset food protein-induced enterocolitis syndrome (FPIES) has been increasingly recognized in recent years. Adult FPIES differs from pediatric FPIES in terms of dietary triggers and symptoms, thus further broadening the clinical phenotypes of the disease. The natural history of FPIES in adulthood is poorly characterized. OBJECTIVE: To evaluate the natural course of FPIES in adults. METHODS: We performed an ambispective study of adults diagnosed with acute FPIES during 2016-2021. Data on age, sex, symptoms, implicated food, and oral food challenge (OFC) outcomes at baseline and during follow-up were analyzed. RESULTS: Forty-two adults were included (83.3% female; median age at diagnosis, 40 years). The predominant symptoms were diarrhea (92.9%) and abdominal cramps (71.4%); vomiting was reported by 59% of patients. The most common triggers were shellfish (n = 19, 45.2%) and fish (n = 19, 45.2%). The mean number of reactions before diagnosis was 6.3 (2-15). Twenty-one OFCs were carried out with the offending food in 15 patients. Six patients achieved tolerance (40%) after a mean of 17.8 months (range, 6-36 months). Twelve of all OFCs performed were positive (57.1%). The absolute leukocyte and neutrophil counts measured before and 1 to 2 hours after the positive challenge showed a mean increase of 3045 and 2736 cells/µL, respectively. Serum tryptase, C-reactive protein, and eosinophil and platelet values did not change significantly after the OFC. CONCLUSION: Some patients may outgrow adult-onset FPIES.

Poor prognosis of food protein-induced enterocolitis syndrome to fish.

BACKGROUND: Fish is the most common causative food of food protein-induced enterocolitis syndrome (FPIES) in Southern Europe. In children with FPIES, the development of tolerance varies according to the culprit food and specifically fish seems to have a poorer prognosis than other solid foods. We sought to evaluate the fish-FPIES resolution rate in children. METHODS: A descriptive retrospective analysis of children with fish-FPIES, followed during the last 20 years, was performed. The offending fish, age and symptoms at onset, the coexistence of atopic diseases and FPIES to other foods were registered. All the children included had undergone an oral food challenge (OFC) with the offending fish. We recorded those children that overcame their fish-FPIES and those that did not outgrow the disease. RESULTS: Seventy children were enrolled in this study (median age: 9 yo; IQR 6.4-13.8). Forty-two (60%) achieved tolerance to the offending fish with a median age of 4 years (IQR: 3-5). Among children ≤5 yo (n = 40), 35 (87.5%) developed tolerance; among 6-8yo (n = 14), 40% developed tolerance; and only 12.5% among those ≥9 yo (n = 16) developed tolerance. Twenty-eight children did not outgrow the disease (median age: 8.9 yo; IQR: 9-13.8). We did not find any statistical differences regarding the offending fish, presence of single vs multiple fish-FPIES, symptoms at the beginning, coexistence of other atopic diseases or the coexistence of other FPIES, between the children who overcame the disease and those who did not. CONCLUSION: One in five children with FPIES to fish will not overcome the disease during childhood.