Emphysematous cholecystitis in a diabetic patient

Clinical History

71-year-old female with a three-day history of abdominal pain, chills, nausea and hypotension. The pain in right upper quadrant initiated after a fatty meal.
The patient had a previous history of metabolic syndrome (diabetes treated with insulin therapy, arterial hypertension and obesity).
Physical abdominal examination revealed tenderness.
The laboratory examinations showed leucocytosis.

Imaging Findings

ABDOMINAL PLAIN FILM:
Shows curvilinear gas collections in the right upper quadrant, which represent gas within the gallbladder wall (Fig. 1).

ABDOMINAL ULTRASOUND:
Distended gallbladder, with a thickened and echogenic wall (7.3mm), secondary to intramural gas and multiple stones. An emphysematous cholecystitis was suspected and it was decided to complete the study with CT (Fig. 2-4).

ABDOMINAL NECT AND CECT (100cc contrast 2, 5cc/sec, delay 70 sec p.i.)
A fluid level in a distended gallbladder, with gas within the gallbladder wall and lumen is found (Fig. 5).
Surrounding adipose tissue is reticularly structured and reaches caudally to the hepatic flexure of the colon, and medially to the second duodenal portion, with an oedematous duodenum wall. (Fig 6, 8)
There is no associated perivesicular fluid collection. There is no sign of aerobilia nor dilatation of biliary ducts and no signs of gallbladder perforation (Fig. 7, 9).
The findings demonstrate emphysematous cholecystitis.

An emergency cholecystectomy was performed confirming the radiological findings.
The isolated organism was Clostridium perfringens.

Discussion

Emphysematous cholecystitis (EC) is an uncommon variant of acute cholecystitis caused by bacterial infection with gas-producing organisms [1]. This condition is clinically indistinguishable from simple acute cholecystitis. The diagnosis is usually established with the use of radiographic studies.
Men are affected twice as commonly as women.
The majority of patients are between 50 and 70 years of age and have underlying diabetes mellitus and other cardiovascular risk factors [2].
Clinical manifestations include right upper quadrant pain, nausea, vomiting, and low- grade fever. These symptoms may progress rapidly, requiring emergency surgical intervention.
Laboratory criteria may reveal abnormal findings as leukocytosis with a left shift.
Commonly isolated organisms include Clostridium welchii and Escherichia coli.
Complications include perforation and sepsis, which are more common than in nonemphysematous cholecystitis.

Plain films may show air in the wall or lumen of the gallbladder. Air-fluid levels in the gallbladder will only be seen on images obtained with a horizontal beam, not on supine radiographs.
Gas may spread to the pericholecystic tissues on late-stage disease.

US may demonstrate highly echogenic reflectors with posterior shadowing and reverberation artefact ("dirty" shadowing and "ring-down" artefact) [3, 4].
A less common but more specific finding is small, non-shadowing echogenic foci rising up from the dependent portions of the GB lumen, similar to effervescing bubbles in a glass (champagne sign) [4].

Gas at GB wall is a critical criterion for CT which is the most sensitive and specific imaging modality for identifying it [5]. CT scan findings include: gallstones within the GB, the cystic duct, or both; more than 3 mm of focal or diffuse thickening of the GB wall; enlargement of the GB, with the transverse diameter measuring more than 5 cm; infiltration of the surrounding fat; increased bile attenuation and GB mucosal sloughing. However, CT scanning is not strictly needed for the diagnosis.

EC is definitively treated with cholecystectomy, although percutaneous cholecystostomy may be used in critically ill patients.
On opening the gallbladder, gas and a foul-smelling purulent exudate may escape from the lumen. Gallstones are detected in 70% of cases. The mucosa usually appears necrotic, congested and haemorrhagic.
Microscopically, necrotic and acutely inflamed mucosa often contains colonies of gram-positive bacilli. Inflammation of the mural and blood vessels is common.

The overall mortality rate for patients with EC is 15%, compared with a rate of less than 4% in uncomplicated cases of acute cholecystitis [2, 4].
Early diagnosis and treatment are the key towards reducing morbidity and mortality in this population.

Differential Diagnosis List

Final Diagnosis

Emphysematous cholecystitis

URL:	https://www.eurorad.org/case/13294
DOI:	10.1594/EURORAD/CASE.13294
ISSN:	1563-4086