While topical first-line therapies for AD (i.e., corticosteroids, PDE4 inhibitors, calcineurin inhibitors) may be intolerable or ineffective in HND, promising options include antifungal agents and more recently, JAK inhibitors, OX40/OX40L inhibitors, and anti-IL-13 therapy. The gene discussed is TNFRSF4; the disease is tooth and nail syndrome.