On the other hand, Wallace et al. reported that baseline serum IgE elevations, in addition to elevations in serum IgG4 and blood eosinophil counts, could be useful predictors of relapses in patients with IgG4-RD treated with rituximab [32], suggesting the significant association between serum IgE and the clinical course or prognosis in this disease. Here, IGHE is linked to immunoglobulin G4-related sclerosing disease.