The new definition of dominant stricture in primary sclerosing cholangitis: Prevalence and clinical significance.

Background and Aims: A new definition of dominant stricture (NDS) has recently been defined for patients with primary sclerosing cholangitis (PSC). Prevalence and clinical features of this, compared to traditional dominant stricture (TDS), have not been reported. Methods: In this single‐centre longitudinal prospective cohort study, all PSC patients who underwent endoscopic retrograde cholangiopancreatography (ERCP) between October 2021 and 2022 were recruited. Symptoms of cholestasis, laboratory values (P‐alkaline phosphatase, P‐Bilirubin), Helsinki PSC‐score, brush cytology findings and need for endoscopic therapy (i.e. dilation, stenting) were prospectively collected. Results: Overall, 228 patients with PSC underwent 248 ERCPs. NDS was detected in 43 (17%; 36 patients) and TDS without NDS (TDS group) was detected in 62 (25%; 58 patients) ERCPs, respectively; in the remaining 143 ERCPs, neither TDS nor NDS was seen (no dominant stricture [NoDS] group). PSC duration (median 8 years) and patient's age did not differ between the three groups; males presented more often with NDS. Patients with NDS were more often symptomatic, had higher cholestatic liver enzymes, advanced bile duct disease and markers of biliary inflammation (p <.001). Patients with NDS needed dilation (81%) and stenting (21%) more often than the TDS group (60% and 5%, respectively). Dysplasia in brush cytology was more common in TDS (5%) and NDS (9%) than in NoDS (3%) groups (p =.04), but did not differ between TDS and NDS groups. Conclusions: Dominant stricture according to the new definition developed in 17% of PSC patients in our cohort and identifies patients with more advanced disease, biliary inflammation and need of endo‐therapy. [ABSTRACT FROM AUTHOR]