Gangrenous cholecystitis

Gangrenous cholecystitis is the most common complication of acute cholecystitis, affecting ~15% (range 2-30%) of patients. 

Epidemiology

Risk factors

• male

• increasing age

• delayed surgery

• cardiovascular disease

• diabetes mellitus

• systemic inflammatory response syndrome ⁵

Pathology

Gangrenous cholecystitis occurs as a result of ischemia with necrosis of the gallbladder wall ⁴. Cystic duct obstruction results in increased gallbladder luminal pressure, which may lead to gallbladder wall ischemia progressing to necrosis. Gallbladder perforation occurs in about 10% of necrotic gallbladders.

Radiographic features

Ultrasound

In addition to features of acute cholecystitis, the following may help diagnose gangrenous cholecystitis ³:

• intraluminal membranes suggesting sloughing of the necrotic mucosa

• asymmetrical wall thickness

  • with possible wall disruption and/or ulceration

• focal perfusion defects on Doppler (representing areas of necrosis)

• variable absence of the sonographic Murphy sign ⁷

  • A negative sonographic Murphy Sign occurs in about a third of gangrenous cholecystitis. This may be attributed to ischemic denervation of the gallbladder ⁶

CT

In addition to features of acute cholecystitis, the following may help diagnose gangrenous cholecystitis ¹:

• gallbladder wall air or lumen gas (emphysematous cholecystitis)

• focal irregularity or defect in the gallbladder wall

• intraluminal membranes

• absence of mural enhancement

• pericholecystic abscess

Treatment and prognosis

Mortality is increased compared to uncomplicated acute cholecystitis, estimated at between 15-50% ⁴.