Although the pathogenetic roles of HDMs (mainly D. farinae and D. pteronyssinus) in AD remain controversial [3], clinical studies have demonstrated that the prevalence of serum-specific IgEs against HDM allergens, the major allergens for patients with IgE-allergic AD, is approximately 70% to 95% in patients with IgE-allergic AD [17,18]. Here, IGHE is linked to Alzheimer disease.