[IgG4-related disease]

IgG4-related disease (IgG4-RD) is an entity first described less than 20 years ago, characterized by tumorous swelling of affected organs. Differentiation from malignant disease, systemic infections and other systemic autoimmune diseases can be challenging. Typical histopathologic findings facilitate a diagnosis in a compatible clinical context. Because nearly every organ system can be affected, management of IgG4-RD is a challenging task requiring multidisciplinary work-up and treatment. Medical treatment usually consists of glucocorticoids, which may be combined with other immunosuppressives. Surgical or interventional treatment may be necessary if complications arise. Since high-quality evidence is lacking for most aspects of the management of IgG4-RD, international collaborative studies are urgently needed.