Acute acalculous cholecystitis

Acute acalculous cholecystitis refers to the development of cholecystitis in a gallbladder either without gallstones or with gallstones where they are not the contributory factor. It is thought to occur most often due to biliary stasis and/or gallbladder ischemia.

Acute acalculous cholecystitis represents 5-10% of cases of acute cholecystitis.

Risk factors for acute acalculous cholecystitis include 2:

  • severe tissue injury (e.g. major trauma and burns)
  • postoperative (especially following major surgery e.g. valvular replacement 13
  • diabetes mellitus
  • malignancy
  • vasculitis
  • congestive heart failure
  • shock
  • cardiac arrest
  • advanced age 12
  • concomitant opioid therapy
  • positive-pressure ventilation (PPV)
  • total parenteral nutrition (TPN)

Acute acalculous cholecystitis usually occurs in critically ill or injured patients (e.g. trauma, burns, sepsis). The risk factors listed above may affect the perfusion of the gallbladder and favor bile stasis leading to injury and inflammation. Subsequent ischemia-reperfusion injury to the gallbladder is also a central pathogenic feature 2,9. A rare cause of acalculous cholecystitis occurring in patients with advanced cancer is gallbladder metastases 10.

When there are no gallstones, the diagnosis is more obvious.

May show gallbladder wall edema, pericholecystic fluid, and gallbladder distention (the first two considered the two most important criteria 2). The sonographic Murphy sign may be positive. A sonolucent intramural layer or “halo” that represents intramural edema may also be present.

A sonogram may be considered highly suggestive of the diagnosis with two of the following major criteria, or one major and two minor criteria fulfilled 14;

  • major criteria
    • gallbladder wall thickness > 3 mm
    • wall striation
    • pericholecystic fluid
    • sonographic Murphy sign
    • intramural gas
    • mucosal sloughing
  • minor criteria
    • echogenic bile or sludge in lumen
    • transverse diameter greater than 5 cm

Tc-99m iminodiacetic acid cholescintigraphy is considered a highly reliable test and may be performed even in acutely ill patients. Ideally, there is non-visualization of the gallbladder.

The importance of recognizing acalculous cholecystitis lies in the fact that these patients have a high rate of recurrence when treated with medical management. As such, cholecystectomy is the definitive treatment. However, patients that are not fit for surgery can undergo percutaneous or endoscopic biliary drainage as alternative therapy, though cholecystectomy may still be performed when the patient improves.

Gallbladder and biliary tract pathology
Ultrasound - general index
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Article information

rID: 18611
Synonyms or Alternate Spellings:
  • Acute acalculous cholecystitis (AAC)

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