A rarer cause of Bouveret syndrome – A case report

Abstract

Introduction and importance

Bouveret syndrome is a rare type of gallstone ileus causing gastric outlet obstruction with high morbidity and mortality risk, and hence important to have a high degree of clinical suspicion on presentation for prompt diagnosis and management.

Case presentation

We present a case of an elderly woman with abdominal pain, haematemesis, and an unremarkable radiograph whose initial emergent endoscopy showed a gastric obstruction and a duodenal diverticulum with a non-bleeding broad based duodenal ulcer. Subsequent computerised tomographic (CT) scan revealed a cholecystoduodenal fistula and gastric outlet obstruction secondary to a 5 cm stone in the duodenojejunal (DJ) flexure. A repeat endoscopy was attempted for endoscopic removal prior to proceeding to open enterolithotomy.

Clinical discussion

This case highlights the challenges in diagnosis and discusses the latest literature on multimodal management consisting of endoscopy and surgery.

Conclusion

The location of the obstructing stone at the duodenojejunal flexure is extremely rare and therefore will add to world literature on Bouveret syndrome.

Highlights

• •Bouveret syndrome is a rare form of gastric outlet obstruction from gallstone ileus.
• •Commonly occurs in elderly patients with multiple co-morbidities.
• •Non-specific signs and symptoms cause delay in diagnosis with subsequent high morbidity and mortality risk.
• •This case describes a very rare location of obstruction at duodenojejunal flexure.
• •Multiple modal management with endoscopic and surgical intervention required

1. Introduction

Bouveret syndrome is a form of gallstone ileus due to either a cholecystogastric or cholecystoduodenal fistula causing a gastric outlet obstruction [1]. Gallstone ileus is a rare complication comprising just 0.3–0.5 % of patients with cholelithiasis, out of which Bouveret syndrome makes up <3 % [2]^, [3]. Despite its rarity, this syndrome carries a significant morbidity and mortality risk (up to 60 % and 30 % respectively) and therefore high clinical suspicion is required for prompt diagnosis and management [4]^, [5]^, [6].

This case report conforms to the guidelines of the SCARE criteria [7].

2. Presentation of case

An 84-year-old woman, independent from home, presented to the emergency department (ED) with 1 day history of haematemesis on background of nausea and intermittent upper abdominal pain for the past few months. She has a background history of hypertension and known cholelithiasis. In ED, she was dehydrated but haemodynamically stable. Initial investigations include haemoglobin of 123 g/L, and mildly raised urea of 8.6 mmol/L. Initial chest and abdominal X-rays showed no pneumoperitoneum or dilated loops of bowel. An emergent endoscopy revealed food debris and 1.5 L of coffee ground fluid in the stomach, and a large posterior wall duodenal diverticulum with a broad-based ulcer at the D1-D2 junction with no active bleeding (see Fig. 1). Food debris and fluid were still present in D3 suggesting a distal obstruction.

Fig. 1.

Initial endoscopy showing broad-based ulcer at D2.

A subsequent CT scan of the abdomen showed gallstone ileus with evidence of pneumobilia, a proximal cholecystoduodenal fistula (with the nasogastric tube coursing through the fistula into the contracted gallbladder), and a 5 cm ectopic gallstone at the duodenojejunal (DJ) flexure (see Fig. 2, Fig. 3).

Fig. 2.

Repeat endoscopy showing impacted gallstone.

Fig. 3.

CT abdo showing impacted 5 cm gallstone in distal duodenum.

She returned to the endoscopy suite the next day for an attempt at endoscopic removal of the gallstone (see Fig. 4). Fulguration of the stone was attempted using electrohydraulic lithotripsy, mechanical lithotripsy, snare, and tripod grasper. However, it was unsuccessful and only partial fulguration of the stone could be performed as it was too large.

Fig. 4.

CT abdo showing cholecystoduodenal fistula containing NGT tip.

The patient was then immediately transferred to the operation suite for a laparotomy. Enterotomy was performed at the DJ flexure, and the stone was extracted measuring 5x4cm (see Fig. 5, Fig. 6). She had an unremarkable recovery and remains asymptomatic and well 11 months post operation.

Fig. 5.

Laparotomy and enterotomy at DJ flexure.

Fig. 6.

Extracted obstructing stone measuring 5x4cm with evidence of partial fulguration.

3. Discussion

Bouveret syndrome was named after a French physician Leon Bouveret after he published 2 cases describing this syndrome in 1896 [6]. Gallstone ileus makes up 1–4 % of intestinal obstruction, caused by migration of a large gallstone through a cholecystoenteric fistula formed from inflammatory process such as repeated episodes cholecystitis [6]. Risk factors for Bouveret syndrome include female gender, age over 70, large stone >2.5 cm and previous history of recurrent cholecystitis [1]. Gallstone ileus can occur in any part of the gastrointestinal tract, however, normally occurs in the narrower lumen of distal small bowel with the terminal ileum being the most common (60–70 %) and the duodenum being the rarest (1–3 %), the latter being Bouveret syndrome [6]. The high morbidity and mortality rate associated with this syndrome is attributed mainly to advanced age and multiple co-morbidities of these affected patients, and the non-specific symptoms leading to delayed diagnosis [6]^, [8].

The most common symptoms of Bouveret syndrome include nausea/vomiting (86 %), abdominal pain (71 %) and haematemesis (15 %) [9]. Common clinical signs are abdominal tenderness, signs of dehydration and abdominal distension [9]. Radiological findings on CT scan or plain radiograph are commonly pneumobilia, ectopic gallstone and dilated stomach, which is also known as Rigler's Triad [2]. CT scan is the gold standard for diagnosis [8]. However, in our case, as the patient's main presentation was haematemesis, and a plain radiograph did not suggest obstruction or other surgical issues, CT scan was not done initially. Instead, the patient proceeded straight to endoscopy for diagnosis and management. According to review of cases, diagnosis from endoscopic visualisation of the obstructing gallstone only occurs in 69 % of the cases, although all initial endoscopies showed evidence of obstruction [1]^, [9]. In our case, the stone was not visualised, but signs of bowel obstruction were noted with 1.5 L of fluid and food debris suctioned. Other interesting finding was also a broad-based ulcer from a diverticulum at 2nd part of the duodenum, which in retrospect, was likely the cholecystoduodenal fistula.

Once diagnosed, the aim of management is for extraction of the obstructing stones via either endoscopic or surgical means. Whilst there is no standardised management, the consensus is for an endoscopic treatment as a first line, despite having an overall low success rate (10 %) depending on the size and location of the gallstone [4]. Endoscopic option, if successful, has low morbidity and mortality making it preferable for high-risk patients. It can also aid as an adjunct pre-operatively such as mobilising the stone to a favourable extraction location [1]. There are multiple endoscopic modalities that can be used to extract the stone: initially with nets or baskets, and if the stone is too large, different forms of lithotripsy can be deployed, such as mechanical, electrohydraulic, intracorporeal laser and extracorporeal shockwave therapy [3]. If successful, all fragments of the stone should be extracted to prevent distal bowel obstruction. For our case, a few of these endoscopic modalities were used to fragment the stone, however, the stone remained too large to succeed.

Operative management remains the main form of treatment, as 90 % of endoscopic management fail. Both open and laparoscopic approach can be used for stone extraction via a gastrostomy, duodenotomy or an enterotomy (such as in our case, where the enterotomy was made just distal to the obstruction at the duodenojejunal flexure). Laparoscopic approach should be preferentially considered over open due to its lower morbidity-mortality risk if expertise and equipment is available [1]. In multiple literature reviews, there is consensus on performing enterolithotomy alone, as opposed to fistula repair with or without cholecystectomy in either a combined or staged procedure [1]^, [2]^, [3]. This is an area of debate which depends on multiple factors such as size and presence of any remaining gallstones, and patient age and co-morbidities which determines the risk-benefit ratio of future recurrence vs surgical risk [3]^, [4]. Typically, the fistula will spontaneously close after simple enterolithotomy if there are no remaining stones, and the chance of recurrence in future is <5 % [3]. For our case, as the patient was elderly and no further stones noted on imaging, only a simple stone extraction was done. She remains well and asymptomatic 11 months on.

4. Conclusion

Bouveret syndrome is a rare form of gallstone ileus that causes gastric outlet obstruction and requires high degree of clinical suspicion. With its non-specific signs and symptoms, there can be a delay in diagnosis or can be incidentally diagnosed during work up for haematemesis or obstruction. Whilst endoscopy has a high failure rate, it should be the first line modality of treatment as it has diagnostic and potentially therapeutic adjunct. Operative management advocated is a simple enterolithotomy with either open or laparoscopic approach. Combined or multistage surgery for fistula repair and cholecystectomy should only be considered for select population with minimal co-morbidities and high chance of recurrence.

Reports of Bouveret syndrome due to obstruction at the DJ flexure are very few, and hence we present this case to add to the world literature.

Consent

Written informed consent was obtained from the patient for publication of this case report and accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal on request.

Ethical approval

This case report is exempt from ethical approval at our institution.

Sources of funding

No funding received.

Author contribution

Dr Phyu Cin Thant: acquisition of data, extensive literature search and writing the report.

Dr Rebecca Thomas: conception and design, supervisor, and revising/editing case report.

Guarantor

Dr Rebecca Thomas

Research registration

N/A.

Declaration of competing interest

There is no conflict of interest.