A 55-year-old woman presents with pruritus, jaundice, and fatigue. Biopsy shows granulomatous destruction of interlobular bile ducts with a lymphocytic infiltrate and 'florid duct lesion.' Serology reveals anti-mitochondrial antibodies (AMA) directed against PDC-E2. What is the diagnosis?

• A Primary sclerosing cholangitis
• B Autoimmune hepatitis
• C IgG4-related cholangiopathy
• D Primary biliary cholangitis (PBC) ✓

Explanation

Primary biliary cholangitis (formerly primary biliary cirrhosis, PBC) is an autoimmune disease characterized by T-cell mediated granulomatous destruction of intrahepatic bile ducts, predominantly affecting middle-aged women. The pathognomonic finding is the 'florid duct lesion' — periductal granulomas destroying small bile ducts. Anti-mitochondrial antibodies (AMA), especially M2 type directed against pyruvate dehydrogenase complex E2 subunit (PDC-E2), are present in >95% of cases. PSC affects large bile ducts and is associated with IBD; ANA/ASMA are autoimmune hepatitis markers; IgG4 cholangiopathy shows IgG4+ plasma cell infiltrates.

Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.