Lemmel Syndrome Without Choledocholithiasis as a Cause of Recurrent Hepatocellular Injury: A Case Report.

Lemmel syndrome is a rare cause of stone-negative biliary obstruction due to external compression of the distal common bile duct by a periampullary duodenal diverticulum (PAD). We report a 67-year-old man with recurrent episodes of liver dysfunction due to Lemmel syndrome. On admission, laboratory tests showed marked hepatocellular injury with cholestasis. Contrast-enhanced CT demonstrated a PAD abutting and compressing the distal bile duct with upstream dilatation, without choledocholithiasis. Endoscopic retrograde cholangiopancreatography (ERCP) with sphincterotomy and balloon sweeping yielded sludge-like bile, after which liver tests rapidly improved. This case underscores the need to consider PAD-related transient obstruction in stone-negative, recurrent hepatocellular flares and highlights the diagnostic-therapeutic value of timely endoscopic biliary decompression.