A 32-year-old woman presents with fatigue, jaundice, and elevated serum aminotransferases (AST 620, ALT 890 U/L). Anti-smooth muscle antibody (ASMA) titer is 1:160 and ANA 1:320. Serum IgG is 2.8 times the upper limit of normal. Liver biopsy shows interface hepatitis with a dense lymphoplasmacytic infiltrate and prominent plasma cells forming 'rosettes' around hepatocytes. What is the most likely diagnosis?
- A Primary sclerosing cholangitis (PSC)
- B Acute hepatitis C infection
- C Drug-induced liver injury (DILI)
- D Autoimmune hepatitis (AIH) ✓
Explanation
Autoimmune hepatitis (AIH) is characterized by the combination of interface hepatitis, dense portal lymphoplasmacytic infiltrates with hepatocyte rosette formation, markedly elevated IgG, and positive autoantibodies (ANA and/or ASMA in Type 1 AIH). The plasma cell-rich infiltrate and hepatocyte rosettes are the histological hallmarks that distinguish AIH from viral and drug-induced hepatitis. PSC is characterized by periductal onion-skin fibrosis; hepatitis C shows lymphoid follicles and steatosis; DILI has a variable pattern but autoantibodies are typically absent or at low titers.
Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.