Occurs after gallstone lodges in bowel (generally terminal ileum - the narrowest intestinal area). The stone gets into the gut through a biliary enteric fistula.
Average age of affected patients is 70 years, more common in women.
In a large surgical series of patients undergoing cholecystectomy described here:
1.8% had a cholecystoenteric fistula
90% of patients with a cholecystoenteric fistula had Mirrizi syndrome (common hepatic duct obstruction caused by extrinsic compression from an impacted stone in the cystic duct)
5.7% of patients had Mirrizi syndrome
PRESENTATION
Classically a subacute obstruction in an elderly female that occurs episodically as the stone passes through and transiently obstructs the GI tract. (Transient) abdo pain, vomitting, abdo distension, increased bowel sounds
Bouveret's syndrome - gastric outlet obstruction secondary to an impacted gallstone in the duodenum or pylorus
Less than 15% of gallstones can be seen on plain film. Other AXR findings - parital or total SBO, pneumobilia. CT scan is likely better to visualize the stone/obstruction and MRCP may be best to define biliary anatomy
TREATMENT
Supportive until definitive treatment.
Surgical - enterolithotmy (with care to examine for >1 stone) +/- concurrent cholecystectomy or delayed laparoscopic cholecystectomy
Alternatives - extracorporeal lithotripsy, endoscopy (not first line)
