[IgG4-related disease]

IgG4-related disease is a systemic fibroinflammatory syndrome of unknown etiology characterized by local inflammatory swelling and tumefactive lesions in one or several organs. It unifies several diseases previously thought to be unrelated. Recently, diagnostic criteria for the disease have been formulated and were complemented by an international consensus on histopathological assessment. In general, the disease activity can be rapidly controlled by high doses of prednisolone (0.6 mg/kg body weight); however, relapses, either local or in other regions, are frequent during tapering of the steroid dose. Commonly used steroid-sparing agents are only partially effective. Persistent local inflammatory activity may result in permanent organ damage. In refractory cases rituximab treatment has been used with good success. In the long-term care of affected patients a probable increased risk of malignancies (e.g. solid tumors and lymphoma) requires attention.