Seven Plus Seven Equals Four

T helper type 2 cells (Th2) has strong correlation with IgG4 disease severity, where its production of the cytokine interleukin 4 (IL-4) is instrumental in the pathogenesis of IgG4-related disease. Dupilumab, a monoclonal antibody and antagonist of IL-4 and IL-13 receptors, is approved for treatment of chronic rhinosinusitis and should theoretically prevent development of IgG4-related disease. Our patient is a 59 year old male with eosinophilic asthma and chronic rhinosinusitis who developed severe progressive orbital inflammatory disease, initially presenting as eosinophilic granulomatosis with polyangiitis but ultimately diagnosed as IgG4 disease despite dupilumab.