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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
A 40-year-old woman complains of having severe back pain for about 3 months and recurrent fever. Her past medical history is significant for ulcerative colitis. On physical examination, the patient is thin and jaundiced. The liver edge descends 1 cm below the right costal margin and is nontender. Laboratory studies show normal serum levels of AST and ALT but elevated serum levels of alkaline phosphatase (420 U/L). Endoscopic retrograde cholangiopancreatography demonstrates a beaded appearance of the extrahepatic biliary tree. Which of the following diseases is a late complication of this patient's condition?
assistant
The correct answer is  Primary sclerosing cholangitis (PSC) is characterized by inflammation and obliterative fibrosis of intrahepatic and extrahepatic bile ducts, with dilation of preserved segments. Approximately 70% of patients with PSC have longstanding ulcerative colitis, although the prevalence of PSC in such patients is only 4%. PSC tends to occur in the third through fifth decades of life, with a significant male predominance (2:1). The clinicopathologic findings are complemented by a characteristic radiographic appearance of a beaded biliary tree, representing sporadic strictures. Cholangiocarcinoma is a late complication of PSC. The other choices are not complications of PSC.Diagnosis: Primary sclerosing cholangitis