Sclerosing cholangitis with thumbprint appearance and incomplete steroid response

Adult bile duct strictures: differentiating benign biliary stenosis from cholangiocarcinoma

Biliary epithelial cells preferentially respond to various insults under chronic pathological conditions leading to reactively atypical changes, hyperplasia, or the development of biliary neoplasms (such as biliary intraepithelial neoplasia, intraductal papillary neoplasm of the bile duct, and cholangiocarcinoma). Moreover, benign biliary strictures can be caused by a variety of disorders (such as IgG4-related sclerosing cholangitis, eosinophilic cholangitis, and follicular cholangitis) and often mimic malignancies, despite their benign nature. In addition, primary sclerosing cholangitis is a well-characterized precursor lesion of cholangiocarcinoma and many other chronic inflammatory disorders increase the risk of malignancies. Because of these factors and the changes in biliary epithelial cells, biliary strictures frequently pose a diagnostic challenge. Although the ability to differentiate neoplastic from non-neoplastic biliary strictures has markedly progressed with the advance in radiological modalities, brush cytology and bile duct biopsy examination remains effective. However, no single modality is adequate to diagnose benign biliary strictures because of the low sensitivity. Therefore, understanding the underlying causes by compiling the entire clinical, laboratory, and imaging data; considering the under-recognized causes; and collaborating between experts in various fields including cytopathologists with multiple approaches is necessary to achieve an accurate diagnosis.

Comparison of intraductal ultrasonography findings between primary sclerosing cholangitis and IgG4-related sclerosing cholangitis

BACKGROUND AND AIM

Comparisons of intraductal ultrasonography (IDUS) findings between primary sclerosing cholangitis (PSC) and IgG4-related sclerosing cholangitis (IgG4-SC) have not been elucidated. We aimed to clarify the differences in transpapillary IDUS findings between PSC and IgG4-SC.

METHODS

We retrospectively compared transpapillary IDUS findings between 15 patients with PSC and 35 patients with IgG4-SC between 2004 and 2014.

RESULTS

IDUS findings of circular-asymmetric wall thickness, irregular inner margin, diverticulum-like outpouching, unclear outer margin, heterogeneous internal echo, and disappearance of three layers were significantly higher in PSC than in IgG4-SC (P < 0.001). Irregular inner margin, diverticulum-like outpouching, and disappearance of three layers were specific IDUS findings for PSC compared to IgG4-SC. Diverticulum-like outpouching on IDUS and endoscopic retrograde cholangiogram (ERC) was observed in 10 (67%) and five (33%) of 15 patients with PSC, respectively. However, based on IDUS and ERC, diverticulum-like outpouching was not observed in any patient with IgG4-SC. All five patients with diverticulum-like outpouching on ERC had diverticulum-like outpouching on IDUS, and five (50%) of 10 patients without diverticulum-like outpouching on ERC had diverticulum-like outpouching on IDUS.

CONCLUSIONS

The IDUS findings differed between PSC and IgG4-SC. Irregular inner margin, diverticulum-like outpouching, and disappearance of three layers are specific IDUS findings for PSC compared to IgG4-SC. IDUS is a more useful procedure than ERC for the early detection of diverticulum-like outpouching.