IGHE and allergic disease: Evidence suggests that the infant microbiome plays a role in IgE-mediated food allergy, asthma, and eczema, but this connection has not been explored with FPIES infants.26 Since maternal antibiotic usage during pregnancy has been associated with allergy, asthma, and eczema in infants, it is plausible that maternal antibiotic usage is associated with FPIES.10,27–29 The increase in maternal antibiotic usage seen in the FPIES group could indicate that the maternal microbiome impacts FPIES development.