A different approach to gallstone ileus

Clinical History

85 years old female patient was admitted via the emergency room where she presented with haematemesis. Anamnesis shows that haematemesis started the day before accompanied with diffuse abdominal pain, general weakness and nausea.

The patient’s medical history shows cholelithiasis diagnosed twelve years before, gastric ulcer diagnosed three years before.

Imaging Findings

At admittance the patient underwent an optical oesophagogastroduodenoscopic examination with no conclusive findings (erosive and haemorrhagic reflux oesophagitis). Duodenal bulb was deformed and further examination was not performed.

Plain abdominal X-ray (Fig. 1) and abdominal ultrasound showed definitive findings aside from ileus, cholelithiasis and chronic cholecystitis. Normally we would perform an abdominal CT examination, but our scanner was unavailable at the time.

The follow-up ultrasound described pneumobilia and a large echogenic rim with acoustic shadow, measured at 65 x 35 x 35 mm (our ultrasound has no PACS connection so we are not able to present images). Also a suspect bilio-duodenal fistula was described.

The barium follow-through examination (Fig. 2, 3) correlated with these findings and gave a good visualisation of a large oval mass blocking the distal passage of contrast medium in the inferior horizontal part of the duodenum.
The mass measured 60 x 30 mm (Fig. 4, 5).

Discussion

After establishing the diagnosis of gallstone ileus, the patient was scheduled for surgery where the large gallstone was removed from the distal part of duodenum. The postoperative period was uneventful and the patient made a complete recovery.

Gallstone ileus is mainly a condition affecting the elderly female population [1, 2]. It is a rare complication of cholecystolithiasis, occurring as a complication in 3% of all cases. However, it causes of up to 25% of all small bowel obstructions in elderly patients (over 65 years old) [3, 4]. It is considered that the constant pressure from a large gallstone causes the formation of a bilio-digestive fistula through which the gallstone is expulsed into the bowels. The most common location is bilio-duodenal (75%) and bilio-colonic fistula (10 - 20%) [5]. The large gallstone can then cause an obstruction with the resultant mechanical ileus [6]. The most common location of the intestinal obstruction by the ectopic gallstone is at the terminal ileum, followed by jejunum and pylorus. The obstruction at the gastric outlet level, is called Bouveret syndrome [7].

According to the ACR Appropriateness Criteria [8], if small bowel obstruction is suspected, the first imaging method should be a routine contrast enhanced CT examination through the abdomen and pelvis, followed by conventional X-ray methods or abdominal MR. Abdominal and pelvic ultrasound are considered the last choice. Since our hospital does not have an MR and our CT was out of order at the time the patient was treated, we were forced to diagnose the patient with conventional X-ray methods and ultrasound.

There are three standard radiologic signs presented in gallstone ileus: pneumobilia, ectopic gallstone and ileus. These are also called the "Rigler Triad" [9]. If two out of the three signs are positive, then they are considered pathognomonic for the diagnosis of gallstone ileus.

The sensitivity of CT for the detection of the Rigler Triad is up to 77.78%, while ultrasound and conventional X-ray imaging produce significantly lower results (14.81% and 11.11% respectively) [10].

Time from admittance to diagnosis of gallstone ileus in this patient was 10 days. Surgery was scheduled and performed on the same day that the diagnosis was made. Thankfully no further complications presented during this time.

Differential Diagnosis List

Final Diagnosis

Gallstone ileus with bilioduodenal fistula

URL:	https://eurorad.org/case/9958
DOI:	10.1594/EURORAD/CASE.9958
ISSN:	1563-4086