Clinical, Endoscopic, and Histologic Benefit With Comprehensive Type IV Hypersensitivity Patch Testing in Adults With Eosinophilic Esophagitis.

Eosinophilic esophagitis (EoE) is a chronic, immune-mediated disorder of increasing incidence. Although empiric elimination diets are commonly used EoE therapies, adoption of allergy testing to guide elimination diets has been more limited. This likely stems from testing that has often focused on immediate type I hypersensitivity (ie, skin-prick or serum-specific IgE testing) rather than comprehensive type IV hypersensitivity patch tests (CPT), which identify delayed-type allergens. Although atopy patch tests have been less successful for food triggers, CPTs can evaluate the potential role of additives and aeroallergens in EoE. Our study aimed to determine if avoiding aeroallergens and additives to everyday products based on a CPT would lead to symptomatic and histologic improvement in patients with EoE who had not responded to proton pump inhibitors (PPIs) alone.