Gallstone ileus (GI) is an infrequent complication of cholelithiasis and is defined as mechanical intestinal obstruction due the impaction of gallstone in the gastrointestinal tract.
This entity occurs in 0.3%-0.5% of patients with cholelithiasis.
It predominantly affects the elderly patient population.1
Despite the rare incidence,
it carries a mortality and morbidity rate of around 7–30% .
Gallstones inflammation of the gallbladder wall causes erosion and leads to a fistula with the duodenum,
which is the exit route for the stones.
Less commonly,
a gallstone may enter the duodenum through the common bile duct and through a dilated papilla of Vater.
The most frequent fistula occurs between the gallbladder and the duodenum,
due to their proximity.2
Gallstones usually impact in the ileum or in the ileocaecal valve.
Occlusion can occur also at other segments of the gut (jejunum 16%,
stomach 14%,
colon 4%,
and duodenum 3.5%)especially if other pathologies are present (for example Crohn disease or neoplastic stenosis).3
Clinically gallstone ileus is preceded by symptoms of acute cholecystitis followed by aspecific signs of mechanical intestinal obstruction which includes vomiting,
colicky abdominal pain,
distention,
and absolute constipation.
Vomitus usually include gastric content but becomes fecaloid if the stone is impacted in the ileum.4
The majority of gallstones smaller than 2 to 2.5 cm may pass spontaneously through a normal gastrointestinal tract and will be excreted uneventfully in the stools.5
Most patients with gallstone ileus are elderly with other concomitant medical illnesses; despite low incidence,
morbidity and mortality rates are high.
Ileal ischemia may develop at the site of gallstone impaction,
due to the pressure generated against the bowel wall and the proximal distention.
Together with the erosive effect of the stone materials,
necrosis and perforation followed by peritonitis may occur.6
Association between Mirizzi syndrome and cholecysto-enteric fistula has rarely been reported.
Mirizzi syndrome is described as a hepatic duct obstruction due to compression “ab estrinseco” of an impacted stone localized in the neck of gallbladder or cystic duct.7
Bouveret’s syndrome is a particular condition of gallstone ileus,
gallstone impaction is in fact located in the pylorus or in the proximal duodenum leading to a gastric outlet obstruction.
Its occurrence is even more rare: only 1–3% of all cases of GI.8
The absence of gallbladder cannot exclude gallstone ileus since there have been reported cases of GI post cholecystectomy as a result of ‘lost’ stone in the intraperitoneal cavity migrating into the bowel through a communicating abscess.5
Computed tomography has proven to be the most accurate diagnostic modality,
but diagnostic criteria validation is required.
Surgical relief of obstruction is the cornerstone of treatment.
Given the high incidence of comorbidities in these patients,
a good judgement in selecting the surgical procedure is required.