Primary Sclerosing Cholangitis
Primary sclerosing cholangitis (PSC) is a disease of the biliary tract, which has seemingly many similarities with the primary biliary cirrhosis (PBC). Nevertheless, these diseases also have many differences including the average prognosis.
Primary sclerosing cholangitis has autoimmune origin, which is similar to PBC. However, while PBC damages small bile ducts in the liver, PSC damages rather larger bile ducts, both intrahepatic (in the liver) and extrahepatic (outside the liver). Unlike PBC, PSC is more common in men than in women and it typically accompanies some forms of ulcerative colitis.
The chronic inflammation of the bile ducts leads to their scarring and narrowing. This is followed by disrupted bile flow and symptoms similar to PBC such as fatigue, loss of appetite, jaundice and itchy skin due to accumulation of bile salts in the skin and subcutaneous tissue. Smaller amount of bile gets into the small intestine causing malabsorption of nutrients including fats and some vitamins. The excessive amount of undigested fat causes greasy and smelly stool. Chronic course of the disease leads to development of liver cirrhosis with portal hypertension with all consequences (ascites, esophageal varices, hepatic encephalopathy and others). The narrowed bile ducts with accumulating bile can be easily infected by bacteria causing recurrent infections of the biliary tract (recurrent cholangitis). Patients with long-term PSC have an increased risk of occurrence of dangerous cancers of the biliary tract that is difficult to treat and has a poor prognosis.
Patient with the mentioned symptoms should visit a doctor and be examined. The blood tests may show elevated level of bilirubin (a substance formed from hemoglobin secreted into bile) and elevated liver tests. In some cases, serological examination of the blood may confirm the presence of certain autoantibodies that attack the bile ducts. The abdominal ultrasound may demonstrate the signs of cirrhosis and portal hypertension. Very useful examinations of the biliary tree are the ERCP and MRCP. Liver biopsy is an invasive method that has a high importance for the right diagnosis. It is a puncture of the liver with obtaining a small sample of tissue for histological examination.
The disease can not be cured, but we can treat the symptoms and complications. We use various drugs to improve the bile flow and medicine to prevent accumulation of bile acids (against skin itching). Any local infections must be treated by antibiotics. When there is a significant narrowing of the extrahepatic bile ducts, it may be possible to solve it by ERCP with an implantation of tubular stent. Advanced stages of the disease may be treated by liver transplantation. Despite relatively little therapeutic successes, the disease has a better prognosis than primary biliary cirrhosis. It progresses relatively slowly and people often survive more than twenty years after the diagnosis.