CRP and immunoglobulin G4-related sclerosing disease: Sasaki T et al. reported that the pattern of organ involvement, atopic history, levels of IgA, and CRP were quite distinctive, and they suggested that the combination of involved orbits, lacrimal glands, salivary glands or pancreas, and an atopic history, IgA < = 330 mg/dL, and CRP < = 0.80 mg/dL may be useful for the differentiation of IgG4-RD from MCD [13].