Inflammatory Bowel Disease in Primary Sclerosing Cholangitis: A Robust yet Changing Relationship

Background: Primary sclerosing cholangitis (PSC) has a well-established association with inflammatory bowel disease (IBD) and may represent a distinctive phenotype. It is unknown whether changes in the clinical and endoscopic presentation of newly diagnosed IBD among patients with PSC might have occurred over time. Methods: Initial clinical and endoscopic presentations of IBD in PSC were studied for 2 different time periods: 1993 to 1997 (early cohort) compared with 2003 to 2007 (recent cohort). Results: The baseline characteristics were similar in the 57 early cohort and 72 recent cohort patients. Compared with the recent cohort, alkaline phosphatase concentrations were higher in the early cohort (7.1 versus 2.6 x upper limit of normal, P = 0.0001). PSC was diagnosed before IBD in the recent cohort compared with the early cohort (50% versus 35%, P = 0.0009). The initial clinical and endoscopic presentations of IBD were similar in the 2 cohorts. The majority of patients had mild pancolitis, whereas rectal sparing and backwash ileitis were detected in one third and one fourth of patients, respectively. In addition, no differences in IBD outcomes or PSC characteristics were revealed. Immunomodulators and biological treatments were more commonly used in the recent cohort when compared with the early cohort (90% versus 56%, P = 0.03, and 13% versus 4%, P = 0.08, respectively). Conclusions: IBD in PSC has unique characteristics, and the clinical features of this unique presentation have remained stable over time. A shift in the timing of diagnosis of the 2 diseases has occurred in recent years, with PSC being more often diagnosed first.