Evaluation of Mayo endoscopic subscore in ulcerative colitis with concomitant primary sclerosing cholangitis

This article relates to the discussion of a recent study published by Wohl <i>et al</i>. Primary sclerosing cholangitis (PSC) is a chronic inflammatory liver disease that affects the intra- and extrahepatic bile ducts and is strongly associated with ulcerative colitis (UC). Endoscopic evaluation of UC is feasible and reliable in routine clinical practice, and the Mayo endoscopic subscore (MES) is one of the most commonly used endoscopic evaluation measures for UC. Patients with PSC-UC are at higher risk of developing cancer and biliary tract cancer. Endoscopic scoring alone appears unreliable, and histopathological evaluation is essential to accurately assess and make effective therapeutic decisions for PSC-UC. Therefore, we aimed to discuss the accuracy of MES in patients with UC and PSC-UC and to explore the consistency between MES and the Nancy histological index.