Primary Sclerosing Cholangitis Common in Long-term IBD Patients

By Will Boggs MD

July 18, 2016

NEW YORK (Reuters Health) - Primary sclerosing cholangitis (PSC) affects as many as one in 12 patients with long-term inflammatory bowel disease (IBD), researchers from Norway report.

"We were surprised that so many patients had cholangiographic signs of PSC, without having any actual clinical or biochemical evidence of PSC," Dr. Aida Kapic Lunder, of Akershus University Hospital and University of Oslo, told Reuters Health by email.

PSC is a chronic inflammatory disease of the bile ducts that can ultimately lead to liver failure and cancer. Liver transplantation is the only potentially curative therapy.

Approximately 50% to 80% of PSC patients also have IBD, and estimates of PSC prevalence range from 0.8% to 5.6% in ulcerative colitis patients and from 0.4% to 6.4% in patients with Crohn's disease.

Dr. Lunder's team used data from the Inflammatory Bowel Disease South-East Norway (IBSEN) study to estimate the frequency and distribution of magnetic resonance cholangiography (MRC) lesions indicating PSC in 470 IBD patients two decades after their initial diagnoses. Just over two-thirds of these patients (n=322, 68.5%) underwent MRC at their 20-year follow-up.

Twenty-four patients (7.4%) screened positive for PSC-like bile duct lesions, including seven patients (2.2%) who had previously been diagnosed with PSC. Two additional patients were subsequently diagnosed with PSC, for an ultimate PSC prevalence of 8.1% (26/322).

The prevalence of PSC-like bile duct lesions was higher in Crohn's disease (9.0%) than in ulcerative colitis (6.8%) and more common in women (9.2%) than in men (5.9%), but neither of these differences achieved statistical significance, according to the June 21 online report in Gastroenterology.

The presence of PSC was associated with extensive colitis among patients with ulcerative colitis, but the extent of colonic involvement was similar in Crohn's disease patients with and without PSC.

PSC was significantly more common in patients with chronic, continuous symptoms and in patients who had higher use of steroids in the first five years after IBD diagnosis. MRC findings were not associated with other IBD medications or biological treatments.

Elevated liver enzymes were evident only among patients with known PSC.

During a median follow-up time of 3.2 years, four patients of 17 examined (23.5%) showed increasing dilatation of the intrahepatic bile ducts. Only three patients (not those that showed progression on MRC) experienced transient liver enzyme elevations.

"PSC is more prevalent in the general IBD population than earlier appreciated," Dr. Lunder concluded. "Clinical and cholangiographic findings do not always go hand in hand."

"We do not advocate screening for PSC in patients with IBD, but MRC should be considered as part of the follow-up," she said. "Diagnosing subclinical PSC today probably does not benefit the patients. This could, of course, change if effective treatment became available."

Dr. Gideon Hirschfield, professor of autoimmune liver disease at the University of Birmingham, UK, told Reuters Health by email, "It is very helpful to understand the true prevalence of PSC in patients with IBD, as it helps us frame the disease much better."

"Further studies such as this are needed globally and over time to fully understand the impact of increased diagnosis at potentially an earlier preclinical/symptomatic stage," he said, adding that such information could "guide us in how we design new drugs and clinical trials."

The study had no commercial funding and the authors made no disclosures.


Gastroenterology 2016.