Repeat patch testing in a patient with allergic contact dermatitis improved on dupilumab

Dupilumab, the first monoclonal antibody approved by the US Food and Drug Administration for the treatment of moderate-to-severe atopic dermatitis (AD), inhibits interleukin (IL)-4 and IL-13 via blockade of IL-4Ra, inhibiting helper T cell (Th)2 signaling. Allergic contact dermatitis (ACD) has a complex and dynamic pathophysiology, in which at least 1 or more of the Th1, Th2, and Th17/22 pathways may mediate reactions. Patients with AD are at risk of ACD. Here we present a patient with AD and ACD who was patch tested before starting dupilumab and during therapy.