The Diagnostic Value And Safety Of Open Food Challenge In The Diagnosis Of Gastrointestinal Food Allergy In Infants

ObjectiveTo evaluate the diagnostic value and safety of open food challenge in the diagnosis of gastrointestinal food allergy in infants.MethodsWe retrospectively reviewed medical records of 55 infants with gastrointestinal food allergy who underwent food challenge at the Department of Gastroenterology, Children’s Hospital of Chongqing Medical University, between February 2012 and January 2016.ResultsOf the 55 infants, 37 infants were diagnosed with FPIPC, 18 with FPIES. The diseases onset age were from 20 hours to 7 months(median age: 30 days). The infants were diagnosed at age from 2 days to 295 days(median: 48 days). The length of history ranged from 2 days to 100 days(median: 23 days). The interval time between diagnosis and food challenge were from 4 to 41 weeks(median: 7.7 weeks). The main clinical manifestation included diarrhea(40 infants,72.72%), bloody stools(36 infants,65.45%), vomiting(23 infants, 41.81%), abdominal distension(10 infants, 18.18%), hematemesis(4 infants, 7.27%), dehydration(7 infants, 12.72%), skin eruption(18 infants, 32.72%), cough(4 infants, 7.27%), etc.After avoidance of suspected food allergens, all allergic symptoms disappeared within 1 day to 47 days. Symptoms in 36 infants disappeared within 3 days, of which 22 infants disappeared within 1 day. There were 38 positive OFCs(1 infant was challenged with both cow’s milk protein and egg) and 18 negative OFCs. Among the positive cases, 35 infants underwent cow’s milk challenge, 1 infant with goat’s milk challenge, 1 infant with cow’s milk and egg challenge. After ingestion of suspected allergenic foods, the initial symptoms appeared after 10 minutes to 54 hours. All the symptoms included rashes(19 cases), diarrhea(17 cases), vomiting(9 cases), hematochezia(3 cases), dysphoria(1 case), and cough(1 case). Blood routine tests and stool routine tests were done 6-8 hours later, with increased blood WBC found in 9 cases and increased EOS in 11 cases. There were 9 cases with WBC in stool and 13 cases with positive OB. No serious allergic reactions occurred during the OFCs.ConclusionThe clinical manifestation of gastrointestinal food allergy is atypical, and the disease onset of which is anonymous. The diagnosis is based on the detail history, clinical manifestation, whether symptoms would disappear after elimination diet and(or) positive OFC. OFC is the gold standard for the diagnosis of food allergy, which is affected by ages, tested foods, and the consistent with food avoidance. Negative OFC indicate that patients are not allergic to the tested foods, but other potential allergenic foods should not be ignored. The open food challenge is an easy, safe and valuable test for the diagnosis of gastrointestinal food allergy.