Acute Severe Autoimmune Hepatitis Presenting as Acute-on-Chronic Liver Failure Requiring Urgent Liver Transplantation: A Case Report.

Autoimmune hepatitis (AIH) is classically a chronic immune-mediated inflammatory liver disease; however, it may present abruptly as acute severe hepatitis and, in a minority of cases, progress to liver failure. Early recognition and prognostic stratification are essential in severe presentations, as some patients may require urgent referral for liver transplantation. We report a 66-year-old female presenting with jaundice and marked hepatocellular injury who rapidly progressed to acute-on-chronic liver failure (ACLF) with multiorgan dysfunction. Despite supportive care and an extensive etiological workup, her condition deteriorated with hepatic encephalopathy, acute kidney injury consistent with hepatorenal syndrome, and infectious complications. A transjugular liver biopsy demonstrated intense inflammatory activity with prominent lymphoplasmacytic infiltrates and interface hepatitis, supporting AIH on a background of previously unrecognized chronic liver disease. Given poor prognostic indicators (Model for End-Stage Liver Disease-Sodium (MELD-Na) score >30 and ACLF grade 3), she was urgently referred to a transplant center and successfully underwent emergency liver transplantation. This case highlights the importance of maintaining a high index of suspicion for AIH in cases of acute liver injury of unclear etiology, performing early and serial prognostic reassessment, and expediting transplant evaluation when advanced organ failure develops.