Primary sclerosing cholangitis (PSC) remains a rare but potentially devastating chronic, cholestatic
liver disease. PSC causes obstruction of intra- and/or extra-hepatic bile ducts by
inflammation and
fibrosis, leading to biliary obstruction,
cirrhosis and
portal hypertension with all associated sequelae. The most dreaded consequence of PSC is
cholangiocarcinoma, occurring in 10-20% of patients with PSC, and with population-based estimates of a 398-fold increased risk of
cholangiocarcinoma in patients with PSC compared to the general population. We use the 4-D approach to endoscopic evaluation and management of PSC based on currently available evidence. After laboratory testing with liver chemistries and high-quality cross-sectional imaging with MRCP, the first D is Dominant
stricture diagnosis and evaluation. Second, Dilation of
strictures found during ERCP is performed using balloon dilation to as many segments as possible. Third, Dysplasia and
cholangiocarcinoma diagnosis is performed by separated brushings for conventional cytology and fluorescence in situ hybridization (FISH), and consideration for direct cholangioscopy with SpyGlass™. Fourt and finally, Dosing of
antibiotics is critical to prevent peri-procedural
cholangitis. The aim of this review article is to explore endoscopic tools and techniques for the diagnosis and management of PSC and provide a practical approach for clinicians.