In a review of the literature concerning autoimmune pancreatitis we had special interest for the concept of IgG4-related pathology as a systemic disease with several clinical manifestations. In general, IgG4-positivity can not only be found in the pancreas, but also at the level of the kidneys, extrahepatic biliary ducts, gallbladder, lungs, salivary glands, lacrimal glands, retroperitoneal tissue, ureters, prostate, meninges and lymph nodes. IgG4 seems to be a central key player in the pathophysiology of this disease.