Primary sclerosing cholangitis (PSC) often affects men in their forties, especially those also suffering from inflammatory bowel disease like ulcerative colitis. The exact reason why it occurs is not known. Genes may predispose a person to developing the disease. It is not an autoimmune disease, though the patient shows the presence of certain antibodies in the blood. Thus, in PSC, the cause of the disease is not known.
Sclerotic cholangitis occurring due to known causes is called secondary sclerotic cholangitis. Some conditions that cause secondary sclerotic cholangitis are:
Stones in the bile ducts
Surgery causing damage to the bile ducts
Damage to the blood supply of the bile ducts
Parasites in the bile ducts
Disorders of the bile ducts present from birth
Chemical agents or drugs