Clinical practice guidelines for IgG4‐related sclerosing cholangitis

Abstract

IgG4‐related sclerosing cholangitis (IgG4‐ SC ) is a distinct type of cholangitis frequently associated with autoimmune pancreatitis and currently recognized as a biliary manifestation of IgG4‐related disease. Although clinical diagnostic criteria of IgG4‐ SC were established in 2012, differential diagnosis from primary sclerosing cholangitis and cholangiocarcinoma is sometimes difficult. Furthermore, no practical guidelines for IgG4‐ SC are available. Because the evidence level of most articles retrieved through searching the PubMed, Cochrane Library, and Igaku Chuo Zasshi databases was below C based on the systematic review evaluation system of clinical practice guidelines MINDS 2014, we developed consensus guidelines using the modified Delphi approach. Three committees (a guideline creating committee, an expert panelist committee for rating statements according to the modified Delphi method, and an evaluating committee) were organized. Eighteen clinical questions ( CQ s) with clinical statements were developed regarding diagnosis (14 CQ s) and treatment (4 CQ s). Recommendation levels for clinical statements were set using the modified Delphi approach. The guidelines explain methods for accurate diagnosis, and safe and appropriate treatment of IgG4‐ SC .

Difficulty in the diagnosis of isolated immunoglobulin G4‐related sclerosing cholangitis

“…Characteristic cholangiographic features may allow discrimination of IgG4‐SC from PSC; short annular or band‐like strictures, diverticulum‐like outpouching, and beaded or pruned‐tree appearance, which are typical of PSC are rarely observed in IgG4‐SC. In contrast, IgG4‐SC has longer strictures and more prestenotic dilatation . Takagi et al .…”

“…IgG4‐SC is frequently associated with AIP, but it is referred to as “isolated IgG4‐SC” when it is not associated with AIP . Clinical practice guidelines for IgG4‐SC have been published . The diagnosis is straightforward if IgG4‐SC is associated with AIP or other IgG4‐related diseases.…”

“…Imaging reflects the characteristic pathological findings of IgG4‐SC. Three characteristic pathological findings are evident in cases of IgG4‐SC . First, inflammation occurs in the submucosa, and the epithelium is preserved.…”

“…Endoscopic biopsy through Vater's papilla of the bile duct is necessary for ruling out cholangiocarcinoma in cases with localized stenosis. However, the sensitivity for detecting malignancy (55–72%) is low …”

“…This combination is also useful for diagnosing type 1 IgG4‐SC because type 1 IgG4‐SC is frequently associated with AIP. EUS is recommended when ERC is not indicated in patients for whom the diagnosis is definite and pathological approaches to the biliary stenosis are unnecessary . EUS can also provide precise information of AIP.…”