Diagnosis of Primary Sclerosing Cholangitis

How do doctors diagnose PSC?

Doctors diagnose primary sclerosing cholangitis (PSC) based on medical and family history, a physical exam, and the results of medical tests.

Medical and family history

The doctor will ask about your symptoms. He or she may also ask whether you have

• a history of inflammatory bowel disease (IBD), particularly ulcerative colitis
• a parent or sibling who has PSC or IBD
• a personal or family history of autoimmune diseases, such as autoimmune hepatitis, type 1 diabetes, celiac disease, and thyroid diseases

Physical exam

Your doctor will examine your body, including your abdomen. He or she will check for

• signs of cirrhosis and liver failure, such as jaundice, which can make the whites of the eyes and skin look yellow
• scratch marks from scratching itchy skin
• signs that the liver and spleen are larger than they should be
• tenderness or pain in the abdomen

What tests do doctors use to diagnose PSC?

Blood tests

Liver tests can show abnormal liver enzyme levels in your blood.

A health care professional will take a blood sample from you and send the sample to a lab.

Liver tests can show abnormal levels of liver enzymes and other substances in your blood. Abnormal levels of certain liver enzymes may be a sign your liver or bile ducts are damaged.

Imaging tests

To diagnose PSC, doctors typically order a special imaging test to examine the bile ducts, such as

• magnetic resonance cholangiopancreatography (MRCP), which uses a magnetic resonance imaging (MRI) machine to create pictures of the bile ducts. MRCP is the most common test that doctors use to diagnose PSC.
• endoscopic retrograde cholangiopancreatography (ERCP), which combines upper gastrointestinal (GI) endoscopy and x-rays to examine the bile and pancreatic ducts. Doctors may also use ERCP to treat narrowed bile ducts.
• percutaneous transhepatic cholangiography (PTC), which is an x-ray of the bile ducts. A health care professional inserts a needle through the skin and into the liver to inject a special dye into the bile ducts. The special dye lets a doctor see the bile ducts on the x-ray.

Doctors may also order other imaging tests to check for signs of PSC, other bile duct or liver problems, or complications. These tests include

• ultrasound, which uses a hand-held device, called a transducer, that bounces safe, painless sound waves off organs to create an image of their structure.
• computed tomography (CT) scans, which uses a combination of x-rays and computer technology to create images of the liver.
• elastography, a special test that measures the stiffness of the liver. Increased liver stiffness may be a sign of fibrosis, or scarring.

Liver biopsy

A liver biopsy is generally not needed to diagnose PSC. However, in some cases, doctors may order a liver biopsy to check for signs of other liver diseases, such as autoimmune hepatitis.

During a liver biopsy, a doctor will take small pieces of tissue from the liver. A pathologist will examine the tissue under a microscope.

Colonoscopy

For people who have PSC and haven’t already been diagnosed with IBD, doctors may recommend a colonoscopy to check for IBD. Many people with PSC have mild IBD and don’t have IBD symptoms.