S5409 Acute Liver Injury During Pregnancy: A Challenging Diagnosis of Autoimmune Hepatitis

Introduction: The etiology of autoimmune hepatitis (AIH) is multifactorial including genetic susceptibility often in conjunction with environmental triggers. This culmination of factors results in a T-cell mediated immune response leading to persistent inflammation of the liver. AIH is more common in women and classically presents in child-bearing aged women. During pregnancy, AIH can have increased maternal and fetal complications. Case Description/Methods: We present a 27-year-old woman with a diagnosis of Crohn’s disease with recent infliximab induction. She improved clinically and became pregnant. At 23 weeks gestation, she presented with severe pruritis and scleral icterus. Laboratory testing revealed elevated bile acids, bilirubin, and liver enzymes. Intrahepatic cholestasis of pregnancy (ICP) was thought to be contributing, but unlikely to explain the severity of liver enzyme elevation. Imaging with right upper quadrant ultrasound and magnetic resonance cholangiopancreatography were unremarkable. Infectious workup including serologies for cytomegalovirus, herpes simplex virus, Epstein-Barr virus, hepatitis A, B, and C viruses, and HIV were negative. Autoimmune work up was significant for positive anti-nuclear antibody (1:320), but anti-mitochondrial antibody and anti-smooth muscle antibody were negative. Infliximab was held for concern of drug induced liver injury (DILI). A liver biopsy was performed which showed acute and subacute panlobular hepatitis with hepatocanalicular cholestasis. Multidisciplinary review including transplant hepatology and pathology believed the presentation was most consistent with underlying autoimmune process triggered by DILI and pregnancy. Prednisone was initiated, and she was continued on 40 mg prednisone with normalization of liver enzymes. She delivered at 32 weeks due to premature rupture of membranes. After delivery, she was started on azathioprine and prednisone was tapered by 5 mg weekly. Discussion: Diagnosing and managing acute liver injury during pregnancy is challenging, as it requires balancing the need for accurate identification and treatment of the liver condition, while minimizing risk to the fetus. While her elevated bile acid levels and pruritis were indicative of intrahepatic cholestasis of pregnancy, the severity of her elevated liver enzymes warranted additional workup. Underlying Crohn’s disease with infliximab exposure during pregnancy likely triggered AIH. This case emphasizes the importance of recognizing coexisting liver processes during pregnancy that can have detrimental maternal and fetal outcomes if left untreated.