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Randomized Double-Blind Placebo-Controlled Crossover Trial for the Diagnosis of Non-Celiac Gluten Sensitivity in
R Francavilla1, F Cristofori1, L Verzillo1
1Interdisciplinary Department of Medicine-Pediatric Section, University of Bari, Bari, Italy.
Objectives:
Non-celiac gluten sensitivity (NCGS) is characterized by intestinal and extra-intestinal symptoms that are related to the ingestion of gluten in subjects who are not affected by either celiac disease (CD) or wheat allergy (WA). In this multicenter study, we aim for the first time to evaluate the prevalence of NCGS in pediatric subjects with chronic functional gastrointestinal symptoms associated with gluten ingestion using a double-blind placebo-controlled (DBPC) gluten challenge with crossover.
Methods:
Among 1,114 children with chronic gastrointestinal symptoms (negative CD and WA), those exhibiting a positive correlation between symptoms and gluten ingestion were eligible for a diagnostic challenge including the following phases: run-in, open gluten-free diet (GFD) and DBPC crossover gluten challenge. Patients were randomized to gluten (10 g/daily) and placebo (rice starch) for 2 weeks each, separated by a washout week. The gluten challenge was considered positive in the presence of a minimum 30% decrease of global visual analogue scale between gluten and placebo.
Results:
Out of 1,114 children, 96.7% did not exhibit any correlation with gluten ingestion. Thirty-six children were eligible; after the run-in and open GFD, 28 patients entered the gluten challenge. Eleven children (39.2%; 95% CI: 23.6-53.6%) tested positive.
Conclusions:
This is the first demonstration of the existence of NCGS in children that reinforce the need for a DBPC for the diagnosis as the diagnosis is ruled out in >60% of cases. The registration identifier in ClinicalsTrials.gov is NCT02431585.
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