Gallstone ileus

What is gallstone ileus?

Gallstone ileus is obstruction of the bowel due to impaction of one of more gallstones. It represents 4% of causes of bowel obstruction in the general population and 25% of obstruction occurring in the elderly.¹ To cause an obstruction, stones usually have to be at least 2.5 cm in diameter.

In gallstone ileus, gallstones migrate through fistulas and become lodged in the gastrointestinal tract with the most common site of obstruction in the ileum (60%), followed by the jejunum (15%), stomach (15%), and colon (5%).²

Stones less than 2.5 cm in diameter may traverse the alimentary canal without causing obstruction. When the gallstone lodges in the duodenum and causes gastric outlet obstruction, it is called Bouveret's syndrome.³

Gallstone ileus epidemiology

• Gallstone ileus is an uncommon complication of gallstone disease, occurring in about 0.3-0.5% of all cases of gallstones.⁴

• It accounts for only about 1-4% of causes of intestinal obstruction, but up to 25% of cases of intestinal obstruction in those over the age of 65.

• It is more common in women than in men and the incidence reflects the prevalence of gallstones with age and sex. It is regarded as 'rare and controversial'.

Gallstone ileus symptoms⁵

The clinical presentation of gallstone ileus is frequently nonspecific with intermittent symptoms of nausea, vomiting, abdominal distension, and pain.

Symptoms

• Abdominal pain is an early sign with vomiting developing later. It tends to become progressively more severe.

• Abdominal pain is colicky in nature, with freedom from pain between spasms. It is periumbilical and is not clearly localised.

• Abdominal distension develops.

• Initially the patient may pass stools or flatus but not later.

• Vomiting occurs some hours after the onset of pain and it may be faeculent.

Signs

• Patients with gallstones are often, but not invariably, obese.

• The patient tends to look unwell.

• The abdomen may be bloated and small bowel peristalsis may be visible.

• Some slight and nonspecific tenderness of the abdomen is common.

• Auscultation will reveal rushes, gurgling and tinkling sounds at times of pain.

• Features of dehydration will develop.

Differential diagnosis

This is between other causes of intestinal obstruction. This may include adhesions from previous surgery. Malignancy almost never occurs in the small intestine.

Colorectal cancer tends to present as chronic blood loss when proximal and obstruction when distal. This is because the contents of the bowel are liquid in the first part and become progressively more solid as they traverse the colon.

Investigations

The main distinguishing features of gallstone ileus are small bowel obstruction with the presence of pneumobilia and a gallstone in the right iliac fossa on X-ray/CT (referred to as Rigler's triad).⁵

• Plain abdominal X-ray should show the typical features of small intestinal obstruction. It may be possible to see air in the biliary tract. It may be possible to see a radio-opaque gallstone.

• Computed tomography (CT) scanning invariably demonstrates a fistulous communication, intraluminal gallstone in the small bowel, pneumobilia and any other co-existing pathology contributing to the impaction of the gallstone. The interpretation of subtle signs on CT scanning requires skill but can increase the accuracy of the diagnosis.

From the practical perspective, plain abdominal films demonstrate small bowel obstruction, ultrasound shows biliary tract pathology and CT makes the final diagnosis. Helical CT can be especially useful.

• Blood tests should include FBC, U&E and creatinine, and LFTs. As surgery is anticipated, blood should be grouped and cross-matched.

In an elderly person, routine CXR and ECG before anticipated surgery are wise.

In view of anticipated surgery, blood should be group and cross-matched.

Associated diseases

Patients with gallstone ileus are often old and frail. Cases of gallstone ileus have been reported in patients whose intestines are strictured due to tuberculosis or other disease.

Gallstone ileus treatment and management⁶

Initial management

An intravenous infusion is required to correct dehydration and to reduce the risk of surgery. A nasogastric tube will decompress the stomach and avoid further vomiting.

Surgery

Gallstone ileus is an abdominal emergency and bowel resection may sometimes be required, especially for intestinal perforation.⁷

The procedure of choice in gallstone ileus remains controversial with possible approaches including enterolithotomy alone (has a lower morbidity and mortality rate),¹ in conjunction with simultaneous cholecystectomy and fistula closure, or a two-stage procedure.

• Removal of the obstruction at laparotomy should be accompanied by a careful search for other gallstones proximal to the obstruction.

• The one-stage procedure should be reserved for stabilised patients. In cases with significant associated comorbidities, enterolithotomy alone may represent the best option.⁸

• A laparoscopic technique has been shown to be effective for some patients with gallstone ileus.⁷

Complications⁴

Complications are common as this is major surgery, usually in a group who are old and frail.

Prognosis

Because the condition tends to affect the old and frail who often have comorbidities, there is a high associated mortality. Fewer procedures are associated with a lower risk of postoperative complications.⁴

• In view of anticipated surgery, blood should be group and cross-matched.