Specific IgG4s offood antigens may be found to be elevated in patients with EoE howevertheir pathogenetic role is still unclear, as they could be an attempt of the immune system to down-regulate the Th-2 response, or a class switch from IgE in the natural history of the disease [3,21,40,43]. Here, IGHE is linked to eosinophilic esophagitis.