Published online Feb 14, 2015. doi: 10.3748/wjg.v21.i6.1956
Peer-review started: June 12, 2014
First decision: August 6, 2014
Revised: October 31, 2014
Accepted: January 8, 2015
Article in press: January 8, 2015
Published online: February 14, 2015
Processing time: 244 Days and 22.3 Hours
AIM: To review the current literature for the specific clinical characteristics of inflammatory bowel disease (IBD) associated with primary sclerosing cholangitis (PSC).
METHODS: A systematical review for clinical characteristics of IBD in PSC was performed by conducting a broad search for “primary sclerosing cholangitis” in Pubmed. “Clinical characteristics” were specified into five predefined subthemes: epidemiology of IBD in PSC, characteristics of IBD in PSC (i.e., location, disease behavior), risk of colorectal cancer development, IBD recurrence and de novo disease after liver transplantation for PSC, and safety and complications after proctocolectomy with ileal pouch-anal anastomosis. Papers were selected for inclusion based on their relevance to the subthemes, and were reviewed by two independent reviewers. Only full papers relevant to PSC-IBD were included. Additionally the references of recent reviews for PSC (< 5 years old) were scrutinized for relevant articles.
RESULTS: Initial literature search for PSC yielded 4704 results. After careful review 65 papers, comprising a total of 11406 PSC-IBD patients, were selected and divided according to subtheme. Four manuscripts overlapped and were included in two subthemes. Prevalence of IBD in PSC shows a large variance, ranging from 46.5% to 98.7% with ulcerative colitis (UC) being the most common type (> 75%). The highest IBD rates in PSC are found in papers reviewing both endoscopic and histological data for IBD diagnosis. Although IBD in PSC is found to be a quiescent disease, pancolitis occurs often, with rates varying from 35% to 95%. Both backwash ileitis and rectal sparing are observed infrequently. The development of dysplasia or colorectal carcinoma is increased in PSC-IBD; the cumulative 10 years risk varying between 0% and 11%. Exacerbation of IBD is common after liver transplantation for PSC and de novo disease is seen in 1.3% to 31.3% of PSC-IBD patients. The risk for development of pouchitis in PSC-IBD is found to be significant, affecting 13.8% to 90% of the patients after proctocolectomy with ileo anal-pouch anastomosis.
CONCLUSION: IBD in primary sclerosing cholangitis represents a distinct phenotype that differs from UC and Crohn’s disease and therefore requires specialized management.
Core tip: Inflammatory bowel disease (IBD) in primary sclerosing cholangitis (PSC) is observed to have different characteristics in comparison with conventional IBD without PSC. Based on these differences a distinct phenotype of IBD is suspected. Existing literature was reviewed for clinical characteristics of IBD in PSC yielding 65 studies consisting of 11406 PSC-IBD patients. A large variation for reported characteristics was found, which seem to be related to case ascertainment. This emphasizes the importance of full colonoscopy and biopsies to accurately diagnose IBD in PSC. Overall however, IBD in PSC shows large differences in comparison with conventional IBD, therefore representing a distinct phenotype.