Primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a disorder characterised by progressive chronic inflammation of the intra- and extrahepatic ducts, eventually leading to obliteration of the ducts. Almost all patients also have IBD, especially ulcerative colitis. It can progress to cirrhosis and there is a high risk of development of cholangiocellular carcinoma. If there is concomitant ulcerative colitis, the risk for colorectal cancer is also elevated.

Clinical features

PSC may present asymptomatically (only abnormal laboratory parameters) as it remains asymptomatic for a long time. Then, nonspecific symptoms like fatigue and pruritus appear. Later, symptoms of cholestasis appear, like jaundice, and itching.

Because most patients with PSC also have concomitant IBD, symptoms of IBD can also be present.

Diagnosis and evaluation

As with any cholestasis, ALP, GGT, and bilirubin are elevated. However, the following findings are typical for PSC:

• Autoantibodies (ANA, ANNA, pANCA)
• Mildly increased AST and ALT

Symptoms of cholestasis often prompts morphological examination of bile ducts with MRCP (first choice) or ERCP, which show multifocal strictures. Ultrasound can also be used to in the evaluation.

Biopsy and histology are not usually necessary for the diagnosis, unless there is suspicion of “small duct” PSC, which cannot be visualised on imaging.

It’s important to screen for concomitant IBD in patients diagnosed with PSC. It’s also important to exclude other causes of sclerosing cholangitis, including IgG4-associated cholangitis, bacterial infection and congenital anomalies.

Treatment

There’s no treatment for PSC which slows the progression. UDCA is of unknown benefit for PSC, but many use it regardless, especially for cholestatic pruritus. Bile acid sequestrants like cholestyramine or rifampin may also help. ERCP with balloon dilation or stent insertion can be helpful in case of severe strictures.

Regular screening for complications is important. This includes:

• Cholangiocarcinoma and gallbladder cancer – annual ultrasound/MRCP and serum CA 19-9
• Colon cancer (if concomitant UC) – colonoscopy every 1 – 5 years

Liver transplantation is the only definitive treatment but is reserved for end-stage disease or intractable pruritus.