IL4 and Alzheimer disease: Dupilumab, an anti-IL-4/IL-13 receptor monoclonal antibody, improves clinical outcomes in pediatric AD, but longitudinal data on culture-based skin and nasal microbial changes remain limited.<h4>Objective</h4>To assess dupilumab efficacy in children with moderate-to-severe AD unresponsive to conventional therapy and to describe skin and nasal microbial colonization patterns at the 12-month time point compared with moderate AD receiving conventional topical therapy and healthy controls.<h4>Methods</h4>Prospective observational study.