Syringotropic hypersensitivity reaction associated with infliximab and leflunomide combination therapy in a child with psoriatic arthritis
A 17‐year‐old boy with refractory psoriatic arthritis and alpha‐1 antitrypsin deficiency who developed a syringotropic hypersensitivity reaction after 9 months of therapy with infliximab and leflunomide is described. Clinically, our patient showed a vasculitic‐like skin rash involving both palms and soles, and histopathological examination revealed a syringotropic lymphocytic infiltrate directed toward the intra‐epidermal portion of the eccrine ducts. These features have not been previously associated with infliximab or leflunomide therapy and represent a unique cutaneous hypersensitivity reaction that does not fit any known description of an immune‐mediated hypersensitivity reaction.