Elimination Diet Strategies and Histologic Remission in Children With Eosinophilic Gastrointestinal Disorders

This is a prospective observational cohort study of children aged 2-17 years diagnosed with eosinophilic gastrointestinal disorders (EGIDs). Children undergoing upper and/or lower gastrointestinal endoscopy for clinical indications will be evaluated using multiple segment-specific biopsies. Patients with histologic eosinophilic infiltration consistent with an EGID, after exclusion of other relevant causes, will be eligible for inclusion.

Elimination diets used in routine clinical practice may include single-, two-, four-, or six-food elimination strategies involving commonly implicated foods such as milk, egg, soy, wheat, nuts/peanuts, and seafood. The type and extent of dietary elimination will be determined independently by the treating physician based on the patient's clinical history and clinical assessment. No dietary strategy will be assigned by the study protocol. Dietary management will be conducted with dietitian support, and nutritional status will be monitored.

Clinical symptoms, anthropometric measurements, laboratory parameters, endoscopic findings, and segment-specific histologic eosinophil counts will be prospectively recorded. Follow-up endoscopy with biopsies from the same gastrointestinal segments is planned as part of clinical care approximately 8-12 weeks after initiation of the elimination diet. Clinical and histologic responses to dietary treatment will be evaluated.

Patients achieving clinical and histologic remission will continue dietary management according to routine clinical care and will subsequently undergo planned food reintroduction. Foods will be reintroduced individually, and recurrence of symptoms and, when clinically indicated, histologic recurrence will be recorded. The study will also evaluate growth, nutritional safety, dietary adherence, and factors associated with clinical and histologic response. No additional invasive procedure will be performed solely for research purposes.

Inclusion criteria

• Age 2-17 years.
• Presence of gastrointestinal symptoms such as abdominal pain, vomiting, diarrhea, hematemesis, or hematochezia.
• Undergoing upper and/or lower gastrointestinal endoscopy for a clinical indication.
• Histologic eosinophilic infiltration consistent with an eosinophilic gastrointestinal disorder.
• Exclusion of other relevant causes of gastrointestinal eosinophilia.

Exclusion criteria

• Inflammatory bowel disease, parasitic infection, celiac disease, drug-associated enteropathy, hypereosinophilic syndrome, or other identified causes of gastrointestinal eosinophilia.
• Known primary immunodeficiency.
• Active malignancy.
• Systemic rheumatologic disease.