Gallstone ileus is intestinal obstruction caused by a large gallstone lodged in the lumen. It is seen often in women, the average age is about 70.
The patient usually presents with obvious small bowel obstruction, either partial or complete. The obstructing gallstone enters the intestine through a cholecystenteric fistula located in the duodenum, colon, or, rarely, the stomach or jejunum. The gallbladder may contain one or several stones, but stones that cause gallstone ileus are almost always 2.5 cm or more in diameter. The lumen in the proximal bowel will allow most of these large calculi to pass caudally until the ileum is reached. Obstruction of the intestine may follow passage of a gallstone through a fistula at the hepatic flexure or may occur even after the stone has traversed the entire small bowel.
In most patients, the findings on physical examination are typical of distal small bowel obstruction. Obstruction of the duodenum or jejunum may give a perplexing clinical picture because of the lack of distention. Right upper quadrant tenderness and a mass may be present.
In addition to dilated small intestine, plain films of the abdomen may show a radiopaque gallstone, and unless one is alert to the possibility of gallstone ileus, the ectopic stone can be a puzzling finding. In about 40% of cases, careful examination of the film will reveal gas in the biliary tree, a manifestation of the cholecystenteric fistula. When the clinical picture is unclear, an upper gastrointestinal series should be obtained, which will demonstrate the cholecystoduodenal fistula and verify intestinal obstruction.
Treatment of Gallstone Ileus
The proper treatment is emergency laparotomy, removal of the obstructing stone through a small enterotomy. The proximal intestine must be carefully inspected for the presence of a second calculus that might cause a postoperative recurrence. The gallbladder should be left undisturbed at the original operation.
Once the patient has recovered, an elective cholecystectomy should be scheduled if the patient complains of chronic gallbladder symptoms. On this basis, interval cholecystectomy will be required in about 30% of patients. The fistula itself is rarely the source of trouble and closes spontaneously in most patients.
The death rate of gallstone ileus remains about 20%, largely because of the poor general condition of patients at the time of laparotomy. In many cases, the patient has developed cardiac or pulmonary complications during a preoperative delay when the diagnosis was unclear.