S3457 When a Tumor Marker Lies: Liver Abscesses and Choledocholithiasis With Elevated CA 19-9 Imitating Pancreatic Cancer

Introduction: Liver abscesses are typically more common in males, with in-hospital mortality ranging from 2.5%-19%, notably with a higher mortality rate when associated with biliary tract disease. In 1 study, roughly 46% of patients had an elevation of Ca 19-9, but only 10% were profoundly elevated >10002. Very few cases have been documented of choledocholithiasis more than 10 years post-cholecystectomy, and those are often associated with migrated clips. Case Description/Methods: We present a 61-year-old woman with history of cholecystectomy 20 years prior who presented with right-sided abdominal pain, nausea and vomiting for 2 days with acute dysarthria and confusion. She was tachycardic and hypotensive, significant labs were a leukocytosis of 35,000 cells/uL, transaminitis with alanine transaminase (ALT) 215 U/L, aspartate aminotransferase (AST) 175 U/L, alkaline phosphatase (ALP) 125 U/L, and a total bilirubin 5.8 mg/dL. Notably, her CA 19-9 was 9,260. Computed tomography abdomen showed diffuse intrahepatic and extrahepatic biliary dilatation without discrete downstream mass or obstructing stone and multiple ill-defined hypoattenuating lesions throughout the liver concerning for metastatic disease. However, Magnetic Resonance Cholangiopancreatography (MRCP) showed a 1.3 cm filling defect in the distal common bile duct with upstream intrahepatic and extrahepatic biliary dilatation. Endoscopic retrograde cholangiopancreatography (ERCP) revealed frank pus from a biliary fistula near the major papilla, choledocholithiasis, and sludge that was swept from the duct. One 10 French × 7 cm plastic stent was placed. Blood cultures were positive for Klebsiella species. She was placed on broad-spectrum antibiotics, which continued for 6 weeks outpatient. Her confusion resolved quickly after antibiotics were started, and she remained at baseline. She had a successful repeat ERCP and biliary stent removal with resolution of CA 19-9 elevation. Discussion: While initially concerning for metastases, our patient was found to have choledocholithiasis with resultant liver microabscesses successfully treated with ERCP and antibiotics. We highlight the importance of keeping choledocholithiasis on the differential in the setting of highly elevated tumor markers, hypoattenuating lesions on the liver, and even cases with cholecystectomies twenty years prior.