Useful biomarkers in pediatric eosinophilic duodenitis and their existence: a case-control, single-blind, observational pilot study.

Objectives: The aim of this study was to determine whether screening for food hypersensitivity could be a clinically useful biomarker for eosinophilic duodenitis in the pediatric population.

Patients And Methods: Twenty-two patients with functional dyspepsia and 19 controls with no significant history of gastrointestinal or allergic disorders were enrolled. Participants underwent skin prick, atopy patch, and serum-specific (S)-IgE, -IgG, and -IgG4 testing to corn, wheat, soy, peanut, milk, and egg. Participants in the patient group also underwent endoscopy with biopsies as part of standard care.

Results: Three participants in the patient group did not exhibit duodenal eosinophilia on biopsy and were excluded from data analyses. The patient group consisted of 13 females and 6 males, 8 to 17 years of age. The control group consisted of 10 females and 9 males, 8 to 17 years of age. Seven patients had at least 1 positive reaction to food by skin prick, atopy patch, or SIgE testing compared with 7 controls; odds ratio 1; 95% confidence interval 0.3 to 3.7. Receiver operating characteristics curves showed SIgG and SIgG4 performed poorly or no better than chance for predicting group assignment.

Conclusions: Allergy screening for the foods tested was not useful as a biomarker for eosinophilic duodenitis in this small study. A higher rate of positive reactions to patch testing was observed in the control group than previous studies have reported. The incidence of a positive food patch test in nonselected subjects needs further investigation. Method standardization and establishment of reference intervals are needed for atopy patch tests, SIgG, and SIgG4 to better evaluate the clinical value of these measures.