IGHE and Alzheimer disease: However, the immunopathogenic roles of common environmental allergens, such as house dust mite (HDM) allergens, in the development of skin lesions in IgE-allergic AD have not yet been precisely clarified [3], although previous studies using animal models have indicated that eczematous skin reactions could possibly be induced by IgE-allergic sensitization [9] and that HDM allergens can promote an IgE-allergic AD phenotype in a mouse model [10].