Prospective, pragmatic standard of care clinical trial comparing dietary therapies of standard dairy elimination diet alone (DED) to dairy elimination plus food additive elimination (FREE)

Eosinophilic esophagitis (EoE) is a chronic inflammatory disorder of the esophagus. Primary symptoms manifest while eating and include dysphagia, chest pain, and food impaction. EoE was first described in the 1990s, but is increasingly recognized worldwide. It affects both adults and children.

Given that EoE is thought to be an allergen driven disease, elimination diets are considered logical and safe first-line treatment options. Elimination diets focus on the removal of the food groups most likely to evoke the inflammatory response (e.g. dairy, wheat, soy, egg, etc.). This is the first study to examine the effects of an additive free diet on eosinophilic esophagitis.

Primary Objective: To compare histologic outcomes (eosinophils per high power field: eos/hpf) of DED and FREE in children with eosinophilic esophagitis.

Secondary Objective: To compare endoscopic outcomes (Eosinophilic Esophagitis Endoscopic Reference scores: EREFs) of DED and FREE in children with eosinophilic esophagitis

Tertiary Objectives: To compare symptomatic (Pediatric Eosinophilic Esophagitis Symptom Severity Module v2.0: PEESS) and quality of life (Peds-QL EoE Module 1) outcomes of DED and FREE in children with eosinophilic esophagitis

The investigators plan to enroll 72 patients over 4 sites each enrolling 18 patients per site in a 16-month period (approximately 1 patient per month per site) having 9 patients per site in each group (DED and FREE).

The investigators will enroll patients > 5- <17 years of age with isolated esophageal eosinophilia (>15 eos/hpf). Patients with food impaction, peripheral eosinophilia > 1,500 µL , concomitant GI inflammatory conditions, history of upper GI tract surgery (e.g. fundoplication), acid reflux by pH probe, anaphylactic food allergies, severe developmental delay, taking recently prescribed inhaled corticosteroids or oral corticosteroids, have other medical conditions likely interfere with the study, has a significant psychiatric condition, has taken a PPI in the last 4 weeks, has taken swallowed steroids in the last 12 weeks, or are not fluent in spoken and written English will be excluded.

Participants will be enrolled at: Nemours Children's Hospital, Orlando, FL; Alfred I Dupont Hospital, Wilmington, DE; Seattle Children's Hospital, Seattle, WA

Once eligibility criteria are met, participants will be randomized to DED or FREE study groups. Participants will receive dietary education. Lead dietitians from each site will be identified and the approaches to dietary education will be standardized. Dietary education will be completed at the baseline visit and during follow up phone calls throughout the study.Each participant will complete all study visits in 12 weeks.

Inclusion Criteria:

1. An Institutional Review Board (IRB) approved written Parental Permission form is signed and dated by the parent or legal representative/caregiver.
2. If applicable, an Institutional Review Board (IRB) approved written Assent form is signed and dated by the participant.
3. The participant/parent(s) or legal representative(s)/caregiver(s) are considered reliable and capable of adhering to the protocol call schedule and dietary requirements.
4. The participant is >2 years to <18 years of age.
5. The participant has isolated esophageal eosinophilia (>15 eos/hpf).
6. The family has access to the internet to complete weekly surveys and to a telephone to complete weekly follow up calls.
7. The biopsy used to diagnose eosinophilic esophagitis was taken no more than 12 weeks prior to the date of enrollment.

Exclusion Criteria:

1. The participant has peripheral eosinophilia > 1,500 µL
2. The participant has concomitant GI inflammatory conditions (e.g. celiac disease, inflammatory bowel disease).
3. The participant has a history of upper GI tract surgery (e.g. fundoplication)
4. Acid reflux by pH probe is suggested (*A pH probe is not required, but may be done as standard of care)
5. The participant has severe developmental delay that, in the opinion of the investigator, could jeopardize the participant's ability to participate in the study.
6. The participant has taken prednisone in the last 12 weeks, or has taken fluticasone or budesonide in the last 8 weeks.
7. The participant has other significant medical conditions that, in the opinion of the provider, would impact the participant's ability to participate in the study.
8. The participant has a psychiatric condition that, in the opinion of the investigator, could jeopardize the participant's ability to participate in the study.
9. The participant does not speak or read English fluently.
10. The participant is currently taking a PPI (If discontinued, no washout required.)
11. The participant is currently on or previously failed a dairy free diet for EoE.