Lemmel syndrome is a rare condition defined as obstructive jaundice caused by a periampullary duodenal diverticulum, in the absence of biliary lithiasis or neoplasia. To date, few cases have been

reported and the etiopathogenesis has not been fully established.

The aim of our study was to illustrate the epidemiological profile and diagnostic approaches for cases of Lemmel syndrome managed in our department   

This was a retrospective descriptive study spanning 5 years, from May 2019 to October 2025,

including all patients admitted for obstructive jaundice who underwent endoscopic retrograde cholangiopancreatography (ERCP). The diagnosis of Lemmel syndrome was established based on clinical, biological, and imaging findings in all patients and on the results of ERCP.

Among the 810 patients who underwent ERCP, 3 patients (0.37%) were diagnosed Lemmel syndrome. All patients were women with a median age of 82 years [79-85]. All patients had cholestatic jaundice associated with pain in the right hypochondrium and epigastrium, two of whom had grade 1 cholangitis and one had grade 2 cholangitis. One patient also presented with pancreatic-type pain and vomiting. Biochemically, all patients (n=3) showed cytolysis and cholestasis jaundice, and one patient had a lipase level more than three times the normal. Contrast-enhanced CT imaging revealed dilation of the common bile duct (CBD) and intrahepatic bile ducts without visible obstruction in all cases (n=3), and associated stage C pancreatitis in one case. 

One patient underwent endoscopic ultrasound, which revealed a large periampullary diverticulum, with the ampulla specifically located on the rim of the diverticulum, compressing the CBD without stones.   

ERCP was performed in all three patients. The major duodenal papilla, with a normal orifice, was located within a periampullary duodenal diverticulum. Contrast injection showed upstream dilation of the common bile duct without stones or neoplasia. Sphincterotomy allowed effective biliary drainage.

The outcome was favorable in all our patients, with normalization of liver function tests.

Although it is a rare condition, Lemmel syndrome should always be considered in patients presenting with obstructive jaundice. Early diagnosis is essential to avoid serious complications. ERCP with sphincterotomy wan be an effective treatment for Lemmel syndrome.