Eosinophilic esophagitis (EoE) is an emerging allergic condition of the esophagus, predominantly triggered by food antigens. Yet, food allergy testing (via skin test or IgE titlre) is suboptimal to detect culprit foods in EoE.  Unfortunately, effective dietary strategies (elemental diet , empiric 6-food elimination diet) are often not popular among patients and physicians because of their high level of restriction and/or numerous endoscopies required. Studies have shown that up to three quarters of patients on a 6-food elimination diet have only one or two food triggers triggering their disease with the most common causative food being cow´s milk, followed by wheat and egg. Therefore, the majority of responders to a 6-food elimination diet would benefit from less restrictive dietary schemes.

In a multicenter study recently published in The Journal of Allergy & Clinical Immunology (JACI), Molina-Infante and Lucendo and colleagues evaluated the effectiveness of a new step-up empiric dietary strategy in 130 pediatric and adult EoE patients. All EoE patients, who were unresponsive to a previous proton pump inhibitor trial, initially underwent a 2-food elimination diet (milk and gluten-containing cereals). Non-responders were gradually offered a 4-food elimination diet (2-food elimination diet + withdrawal of egg and legumes) and then a 6-food group elimination diet (4-food elimination diet + withdrawal of nuts and fish/seafood), in case of unresponsiveness.

The authors found that 2-, 4- and 6-food elimination diets were effective in 43%, 60% and 79% of patients, with no differences between children and adults. Compared to initial 6-food elimination diet, a step-up strategy reduced endoscopic procedures and diagnostic process time by 20%. In responders to a 2-food elimination diet, the most frequent culprit foods were milk (52%), gluten-containing grains (16%) and both (28%). EoE induced only by milk was present in 18% and 33% of adults and children, respectively. Interestingly, 90% of responders to a 2- or 4-food elimination diet had one or two food triggers, whereas all responders to a 6-food had 3 or more.

Compared to a 6-food elimination diet, this new step-up empiric approach has potential to quickly identify a majority of responders, avoiding unnecessary dietary restrictions, likely saving endoscopies and shortening the diagnostic process. Most responders to a 2-or 4-food were shown to have one or two food triggers, so these patients may be best candidates for long-term treatment by avoidance of the culprit foods.  These findings provide useful and realistic clinical information on the efficacy of different empiric dietary strategies and the most frequent causative foods, suggesting that the 6-food elimination diet may be a latter rather than first resort for highly motivated patients. This new step-up approach has potential to ease decision-making in clinical practice and help engage both EoE patients and physicians with dietary therapy.

The Journal of Allergy and Clinical Immunology (JACI) is the official scientific journal of the AAAAI, and is the most-cited journal in the field of allergy and clinical immunology.