Introduction

Gallstone ileus (GI) is defined as a mechanical obstruction due to impaction of one or more large gallstones within the gastrointestinal tract. The pathogenesis is mainly due to gallstone migration through a cholecystoduodenal fistula with impaction in different areas of the gastrointestinal tract; this condition is considered a chronic complication of cholelithiasis¹ which is associated with a risk of gallstone ileus of 0.5%, mainly in elderly women^2,3. The obstruction may occur from the duodenum (Bouveret syndrome⁴) to the sigmoid colon. Morbidity and mortality are about 18%⁵.

The aim of our study is to analyze the data and the results obtained in patients with GI treated in a public hospital.

Material and methods

We conducted a retrospective and descriptive study of five patients with GI treated between December 2017 and January 2020. The demographic and clinical data, the results of the imaging tests, treatments indicated and complications were analyzed (Table 1).

Table 1 Patients with gallstone ileus (GI) 

Results

Most patients (n = 4) were women and mean age was 66 years (range: 62-72). The clinical presentation was mechanical obstruction in four patients and perforation in one. In all the cases, the computed tomography (CT) scan made the diagnosis of GI (Fig. 1 A and B). All the patients underwent laparotomy within 24 hours since hospital admission. The surgeon was a staff physician in three cases and a resident in the remaining cases. Laparoscopy was not indicated due to the lack of availability and experience. The antibiotics administered were cephazolin 1 g intravenously during induction of anesthesia in four patients and ceftriaxone and metronidazole in the patient with perforation. We performed enterolithotomy in four cases and bowel resection in the case with perforation due to direct high-pressure compression by the impacted stone (Fig. 2).

Figure 1 Computed tomography scan. A. Obstruction in the terminal ileum caused by gallstone impaction. B. Endoluminal gallstone and pneumobilia (arrow). 

Figure 2 A. The gallstone is identified. B. Enterolithotomy. C. Gallstone removal. D. Necrosis and perforation of the wall due to gallstone impaction. 

The obstruction occurred in the ileum; one stone was removed from three patients, two from one and five from the remaining patient. The diameter of the stones impacted was > 2.5 cm. During the postoperative period one patient died due to sepsis, and two minor complications developed (one seroma and one surgical site infection). Four patients were discharged between postoperative day four and six; only two patients returned to solve the underlying cholecystoduodenal fistula.

Discussion

Gallstone ileus is an uncommon disease and accounts for 1-4% of cases of bowel obstruction in the general population. The risk is higher in elderly patients⁶.

In our group, mean age was 66 years and most patients were women (female-to-male ratio 4:1), in coincidence with the international literature^3,6,7.

The clinical manifestations are initially unspecific and related to the site of gallstone impaction and the time elapsed since the stone began to migrate into the gastrointestinal tract. Thus, most patients may present with nausea, vomiting, intestinal colic, abdominal bloating, pain in the upper right quadrant, fluids, electrolytes, and acid-base imbalance, dehydration, fever and acute perforated abdomen as a late manifestation.

This condition is not suspected until the full clinical signs develop; however, the diagnosis is usually made by imaging tests or during exploratory laparotomy due to its low prevalence. The preoperative diagnosis can be suspected in elder patients with the Mordor triad: history of cholelithiasis, clinical signs of cholecystitis and bowel obstruction of sudden onset⁶.

The main differential diagnoses are obstructions due to adhesions, phytobezoar and tumors. The presentation as acute bowel perforation has been reported by Browning et al. in a case series, but this manifestation is very uncommon⁸.

The plain abdominal radiography is the initial test performed in bowel obstructions. The radiological signs of GI constitute the Rigler triad of pneumobilia, ectopic radio opaque gallstone, and intestinal distension. The presence of two of these signs makes the diagnosis of GI⁶. However, the sensitivity and specificity of abdominal radiography are low, but the association with abdominal ultrasound increases the diagnosis sensitivity up to 74% in the presence of pneumobilia and ectopic gallstones⁹.

Abdominal radiography was performed in three of our patients; only dilated small-bowel loops were seen in all the cases. Ultrasound was not indicated.

Computed tomography scan identifies the Rigler triad in above 90% of the cases and is considered the gold standard method for the diagnosis of GI^6,10. In addition, uncommon complications of GI as perforation may be visualized⁹.

As with all the cases of occlusive acute abdomen, laparotomy is the most used approach for emergency surgery of GI.

Video-assisted laparoscopy has also been described. Morberg et al. compared a series of patients with GI operated by a laparoscopic or open approach and concluded that morbidity and major complications are less common in the group undergoing laparoscopy, without differences in mortality within 30 days¹¹. In Argentina, Ríos et al. reported the results of video-assisted laparoscopy in 20 patients with GI; in their series, two patients required conversion to open surgery due to technical issues. The authors concluded that video-assisted laparoscopy is a safe and efficient method to treat GI¹².

In our experience, most gallstones caused obstruction by impacting the terminal ileum. In a review of 1001 cases of GI, Reisner et al. reported that the most common sites of gallstone impaction were the ileum (50% - 60.5%), jejunum (16.1% - 26.9%), duodenum (3.5% - 14.6%) and colon (3 - 4.1%)¹³.

Gallstones size was > 2.5 cm in all the cases, similar to the one described by Syme et al., who reported that those gallstones with a diameter > 2.5 cm had greater risk of impaction¹⁴. A thorough exploration should be carried out to look for secondary gallstones, as they may cause of a new GI in the postoperative period.

Since Reisner et al. reported mortality rate of 11.7% in patients undergoing enterolithotomy alone (two-stage surgery) versus 16.9% in those with associated cholecystectomy and fistula closure (one-stage surgery), two-stage surgery was considered the most convenient option¹³. However, enterolithotomy alone has 5% of recurrence and should be indicated only in unstable patients with high preoperative risk.

Other relevant studies comparing one-stage versus two-stage strategies reported similar results for morbidity and mortality and concluded that the strategy should be indicated based on the patient’s clinical status¹⁵. Two-stage surgery has the disadvantage of requiring two anesthetic settings, longer hospital length of stay and higher costs; nevertheless, it is the best option for critically ill patients and in case of surgical teams not trained in one-stage procedures.

Finally, the question is why there are still chronic complications of cholelithiasis in the 21st century. There may be social, economic and cultural aspects in our environment limiting the access to early cholecystectomy.

Conclusion

Gallstone ileus is a rare condition more likely to affect women. Computed tomography scan is the method of choice for the diagnosis. The most adequate approach and timing to solve the cholecystoduodenal fistula are controversial and will be defined on the basis of the patient’s general conditions and the experience of the surgical team.