S2697 Overlap Syndrome of Primary Sclerosing Cholangitis and Autoimmune Hepatitis With Concomitant Findings of Crohn’s Disease

Introduction: Autoimmune Sclerosing Cholangitis (ASC) or Overlap Syndrome refers to the overlap of immunological, clinical, and histological features of both Autoimmune Hepatitis (AIH) along with either Primary Biliary Cholangitis or Primary Sclerosing Cholangitis (PSC). ASC, in general, is more common in children and younger adults, with AIH/PBC variant more common than AIH/PSC. There is a reported association in some cases of ASC with Inflammatory Bowel Disease (IBD). We are presenting a case of a 28-year-old male who is diagnosed with AIH/PSC with IBD, however some of these diagnoses’ classical findings are not present. Case Description/Methods: A 28-year-old South Asian male with no remarkable past medical history presented with jaundice, decreased appetite, RUQ tenderness, and unintended weight loss. Diagnostic workup is remarkable for AST 895, ALT 674, ALP 217, T. Bilirubin 8.18, D. Bilirubin 6.08, Positive Smooth Muscle Antibodies (Abs), Soluble Liver Antigen IgG Abd, IgG4, and atypical p-ANCA. Negative workup includes Antinuclear Abs, Anti-Mitochondrial Abs, C-ANCA, and P-ANCA. MRI/MRCP is remarkable for splenomegaly, intrahepatic biliary ductal dilation with a 1.4 x 1.3 enhancing nodule in the porta hepatis. ERCP revealed periportal and peripancreatic lymph nodes s/p biopsy (negative for lymphoma), very slight opacification of the Common Bile Duct and the Common Hepatic Duct concerning for severe strictures (Fig.1). Percutaneous Biliary Tube Placement and Trans-jugular liver biopsy performed. The biopsy features interface hepatitis with lymphoplasmacytic infiltrate, minimal lobular inflammation, but no evidence of periductal fibrosis (Fig.2). Clinically significant portal hypertension is evident with Hepatic Venous Pressure Gradient of 10 mmHg. Colonoscopy was performed and reveals patchy edematous, erythematous, and friable mucosa with erosions in a skipped pattern (Fig.3), suggestive of Crohn’s Disease (CD). The patient was initiated on prednisone, cholestyramine and transferred for liver transplant evaluation. Discussion: AIH/PSC occurs less commonly with CD than with Ulcerative Colitis. Moreover, such findings have been rarely reported among South Asians. Some histological (periductal fibrosis) and clinical (IBD) findings were not overtly present which made the diagnosis challenging. Given the worse prognosis and higher risk of associated malignancy when present, higher clinical suspicion is needed for prompt diagnosis, treatment, and outcomes.Figure 1.: ERCP showing severe strictures of the distal common bile duct.Figure 2.: (A) Dense neutrophilic infiltrate involving periportal hepatocytes with intermixed. lymphocytes. (B) Moderate mixed lymphoplasmacytic portal-based inflammation with interface hepatitis (bracket), reactive bile ducts and ductules, lacking onionskin or periductal fibrosis (yellow arrow).Figure 3.: Colonoscopy revealing edematous, erythematous, and friable mucosa with erosion in a skipped pattern with areas of normal mucosa intervening areas with inflammation.