Immunoglobulin G4-related disease (IgG4-RD) is a systemic disease characterized by lymphoplasmacytic inflammation, fibrosis, and elevated levels of IgG4 in tissues and eventually in the blood. IgG4-RD is a recently described disease and encompasses classic entities such as Riedel’s thyroiditis, Mikulicz syndrome, and Küttner’s tumor. It is a rare disease that affects middle-aged men, especially...
