DDW ePoster Library

Number: Tu1346
ROLE OF ATYPICAL FOOD ALLERGIES IN FUNCTIONAL DYSPEPSIA: EVALUATION BY SIX-FOOD ELIMINATION DIET AND CONFOCAL LASER ENDOMICROSCOPY FOOD ALLERGY TESTING

Society: AGA
Track: Functional GI and Motility Disorders

Author(s): Jolien Schol¹, Lukas Michaja Balsiger², Joran Toth², Lucas Wauters¹, Karen Van Den Houte², I-Hsuan Huang², Tim Vanuytsel¹, Florencia Carbone¹, Jan F. Tack^{1, 3, 4}

Institution(s): 1. Katholieke Universiteit Leuven Universitaire Ziekenhuizen Leuven, Leuven, Flanders, Belgium. 2. Katholieke Universiteit Leuven, Leuven, Flanders, Belgium. 3. Goteborgs universitet Sahlgrenska Akademin, Goteborg, Sweden. 4. Rome Foundation, Raleigh, NC, United States.

Introduction: Functional dyspepsia is defined by Rome IV criteria and comprises the subgroups postprandial distress syndrome (PDS) and epigastric pain syndrome (EPS). In PDS, characterized by early satiety and postprandial fulness, duodenal increased eosinophil counts and decreased mucosal integrity have been implicated in symptom generation. Food-induced local allergic type reactions are a major candidate cause for these alterations. Confocal laser endomicroscopy (CLE) previously showed acute food-triggered disruption of the duodenal epithelial barrier in irritable bowel syndrome (IBS).
Aim: The aim of the current study was to evaluate whether common allergenic foods may contribute to symptom generation in PDS and whether this involves CLE-detectable atypical duodenal food allergic reactions.
Methods: In Rome IV PDS patients, classical allergic sensitization to nutrients was excluded by serum IgE tests. Patients followed a six-food (wheat, milk, egg, nuts, soy and (shell)fish) elimination diet for 8 weeks and filled out the validated Leuven Postprandial Distress Scale diary. A diet-induced decrease in PDS score of Â0.7 from baseline was considered a response. CLE was performed during upper GI endoscopy after i.v. fluorescein 10% administration and duodenal mucosal integrity was visualized before and after sequential application of dissolved aliquots (5mL) of fish, nuts, egg white, soy, milk and wheat protein. The procedure was stopped after a positive reaction. Duodenal biopsies were obtained after food exposures to evaluate trans-epithelial electrical resistance in Ussing chambers and compared to the same measures at an index upper endoscopy. Data are reported as mean±SEM. Results were considered significant if p<.05.
Results: In ten recruited patients (80% female, 36±4y, BMI 23.0±1.0 kg/m^2) the PDS score improved significantly on six-food elimination diet (1.8±0.22 to 0.9±0.26 (p<0.0001)) generating an 80% responder rate. Six PDS patients (100% female, 35±8y, BMI 22.2±0.9 kg/m^2), of whom 50% had overlap with EPS and 33% with IBS, underwent CLE. In all patients, acute extravasation of fluorescein and cell shedding was identified on CLE after food exposure (fig.1). These acute food-triggered disruptions of the epithelial barrier occurred in reaction to wheat (33%), egg white (33%), soy (16%) or milk (16%). Compared to baseline, transepithelial duodenal electrical resistance tended to decrease after food exposure (39.6±4.6 Ωcm^2 vs.24.2±4.3 Ωcm^2, p=0.057).
Conclusion: In PDS, CLE demonstrates duodenal atypical food-allergy-type reactions and a 6-food elimination diet improves symptoms. CLE findings of food-triggered disruption of the epithelial barrier are consistent with ex vivo permeability measurements. These observations confirm a role for food-induced duodenal mucosal alterations in the pathophysiology of PDS.