Spontaneous Biliary Ascites with Secondary Bacterial Peritonitis: A CaseReport

Biliary ascites is a rare form of ascites resulting from disruption of biliary tract integrity, and spontaneous, non-traumatic, non-iatrogenic perforation of the gallbladder or bile ducts is an exceptionally uncommon cause in adults. We report a 65-year-old man who presented with right upper quadrant pain, jaundice, fever, diarrhea, and progressive abdominal distension following an episode of untreated choledocholithiasis. Cross-sectional imaging, including ultrasound, MRCP, and contrast-enhanced CT, confirmed obstructive choledocholithiasis and moderate ascites but failed to demonstrate a bile leak. Diagnostic paracentesis revealed a low serum-ascites albumin gradient of 0.8 g/dL with a markedly elevated ascitic-to-serum bilirubin ratio of 6.7 and neutrophil-predominant ascitic fluid, consistent with biliary ascites complicated by secondary bacterial peritonitis. Hepatobiliary scintigraphy with SPECT/CT subsequently localized an active biliary leak. Exploratory laparotomy revealed approximately two liters of biliary ascites and a phlegmonous perforation of the gallbladder fundus; cholecystectomy with common bile duct exploration, stone extraction, and T-tube closure were performed, with an uneventful postoperative recovery. This case highlights spontaneous gallbladder perforation secondary to obstructive choledocholithiasis as a rare but treatable cause of biliary ascites and secondary bacterial peritonitis and reinforces the diagnostic value of ascitic fluid analysis and hepatobiliary scintigraphy when conventional imaging is inconclusive.