A 35-year-old man with long-standing ulcerative colitis presents with pruritus and elevated alkaline phosphatase (420 U/L). MRCP shows multifocal strictures with beading of both intrahepatic and extrahepatic bile ducts. Which autoantibody is most commonly associated with this condition?
- A Anti-mitochondrial antibody (AMA)
- B pANCA ✓
- C Anti-smooth muscle antibody (ASMA)
- D Anti-LKM-1
Correct answer: B. pANCA
Explanation
Primary sclerosing cholangitis (PSC) is characterized by multifocal bile duct strictures and strong association with inflammatory bowel disease (especially ulcerative colitis). pANCA is positive in 60-80% of PSC patients. AMA is the hallmark of primary biliary cholangitis. ASMA and anti-LKM-1 are characteristic of autoimmune hepatitis types 1 and 2 respectively.
Reference: Harrison's Principles of Internal Medicine, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.