[Recent Updates of Immunoglobulin G4-related Pancreatobiliary Disease]

Abstract

Type 1 autoimmune pancreatitis and IgG4-related sclerosing cholangitis (IgG4-SC) are the pancreatobiliary manifestations of IgG4-related disease. IgG4-related disease is a newly named fibroinflammatory condition that is characterized by tumefactive lesions that contain dense lymphoplasmacytic infiltrates rich in IgG4-positive cells and often by elevated serum IgG4 concentrations. IgG4-related pancreatobiliary disease is often disguised as pancreatobiliary malignancies owing to its tumefactive nature and clinical presentations, such as obstructive jaundice. The differentiation of IgG4-SC from primary sclerosing cholangitis is also essential because of the significant differences in treatment responses and prognosis. A timely diagnosis of IgG4-related pancreatobiliary disease can lead clinicians to prescribe adequate glucocorticoid treatment that can reverse the pancreatobiliary duct strictures and obstructive jaundice. On the other hand, the diagnosis of IgG4-related pancreatobiliary disease is sometimes challenging because there is no single diagnostic clinical test. The diagnosis of IgG4-related pancreatobiliary disease rests on fulfilling the diagnostic criteria, including imaging, serology, other organ involvement, histology, and response to steroids. Approximately 50% of patients with IgG4-related pancreatobiliary disease experience relapse, despite IgG4-related pancreatobiliary disease showings a favorable short-term prognosis after glucocorticoid therapy. To reduce the relapse, long maintenance treatment for 3 years may be necessary. The purposes of this review were to emphasize the clinical problem of diagnosing IgG4-related pancreatobiliary disease as well as to highlight the use of the published guidelines for the diagnosis and management of IgG4-related pancreatobiliary disease.

Keywords: Autoimmune pancreatitis; IgG4-related sclerosing cholangitis; Immunoglobulin G4-related disease.

Fig. 1

Imaging features of autoimmune pancreatitis, immunoglobulin G4-related sclerosing cholangitis, and other organ involvement. (A) Diffuse enlargement of pancreatic parenchyma with a capsule-like rim. (B) Multiple round or wedge-shaped lesions (arrows) in the kidney. (C) Retroperitoneal fibrosis (arrows) encasing the aorta. (D) Diffuse irregular narrowing (arrows) of the main pancreatic duct. (E) Bile duct wall thickening (arrows) with a preserved bile duct lumen. (F) Hilar bile duct stricture with an intrahepatic bile duct stricture.