Acute Acalculous Cholecystitis

The Gallstone Elimination Report

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Acute gallbladder inflammation in the absence of stones, AAC, is seen in 2% to 15% of patients undergoing cholecystectomy and accounts for 47% of cases of postoperative cholecystitis and 50% of children with acute cholecystitis. It is difficult to make the diagnosis of AAC clinically and on imaging.49

AAC has a mortality rate approaching 60% and should be considered in every postoperative, posttraumatic, or coronary care patient with sepsis.50 AAC typically results from a gradual increase of bile viscosity because of prolonged stasis that leads to functional obstruction of the cystic duct. Mural necrosis occurs in 60% of cases, and gangrene and perforation are common.1,51

Sonographic findings of AAC include gallbladder distention and sludge, with more specific signs of mural thickening, hypoechoic regions within the wall (Fig. 10A), peri-cholecystic fluid, diffuse increased echogenicity within the gallbladder resulting from hemorrhage, pus, intraluminal membranes, and a positive sonographic Murphy's sign.11

CT demonstrates inhomogeneous mural thickening (see Fig. 10B), perihepatitis, pericholecystic inflammation, and increased attenuation within the gallbladder lumen.

Diagnostic percutaneous aspiration of intraluminal bile under sonographic guidance confirms the diagnosis. Percutaneous cholecystectomy can help temporize the critically ill patient with AAC.52

COMPLICATIONS OF ACUTE CHOLECYSTITIS Empyema

Suppurative cholecystitis (empyema) develops when pus fills the distended and inflamed gallbladder. The complication usually develops in diabetic patients and may behave like an intraabdominal abscess with rapid progression of symptoms. On ultrasonography, pus within the gallbladder resembles sludge. On CT scan, the attenuation of the intraluminal pus is high (>30 HU). The diagnosis can be established by sonographically guided percutaneous needle aspiration of the gallbladder.2-4

Cholecystitis Mri

Fig. 10. Acute acalculous cholecystitis: imaging features. (A) Sonogram shows marked mural thickening of the gallbladder with hypoechoic regions (arrows) within the wall. L, gallbladder lumen. (B) CT in a different patient shows marked mural thickening (arrows) of the gallbladder with hypo- and hyperenhancing areas. Both patients were in the intensive care unit.

Fig. 10. Acute acalculous cholecystitis: imaging features. (A) Sonogram shows marked mural thickening of the gallbladder with hypoechoic regions (arrows) within the wall. L, gallbladder lumen. (B) CT in a different patient shows marked mural thickening (arrows) of the gallbladder with hypo- and hyperenhancing areas. Both patients were in the intensive care unit.

Gangrenous Cholecystitis

Gangrenous cholecystitis is associated with significantly increased morbidity and mortality and usually requires emergent surgery. This complication is characterized by intramural hemorrhage, mucosal ulcers, and intraluminal purulent debris, hemorrhage, and strands of fibrinous exudates.2-4

There are several sonographic findings that suggest the diagnosis of gangrenous cholecystitis in the appropriate clinical setting: intraluminal membranes (Fig. 11 A) relating to strands of fibrinous exudates and desquamated mucosa causing coarse, nonlayering intraluminal echoes. In addition, there may be marked asymmetry of the thickened gallbladder wall because of the presence of intramural hemorrhage or microabscess formation. Complex pericholecystic fluid collections containing debris are usually the result of microperforations of the gallbladder.53,54

CT scan may demonstrate intraluminal membranes, mural necrosis, intramural or intraluminal hemorrhage or gas, pericholecystic abscess (see Fig. 11B), and irregular or absent gallbladder wall enhancement during contrast-enhanced CT.55-60

Emphysematous Cholecystitis

Emphysematous cholecystitis develops in fewer than 1% of cases of acute cholecystitis and is more common in men and in patients with diabetes and splanchnic ischemia.61 This rapidly progressive and often fatal disease is characterized by the presence of gas within the wall or lumen of the gallbladder. Clostridium perfringens, Clostridium welchii, Escherichia coli, and Klebsiella are the most common gas-forming bacteria that cause this disease. Patients with emphysematous cholecystitis have a fivefold increased risk of perforation.61

The CT (Fig. 12A) and MRI diagnosis of emphysematous cholecystitis is fairly straightforward if intraluminal or intramural air is present. The diagnosis may be more difficult to establish sonographically. Intraluminal gas produces hyperechoic reflectors in the nondependent portion of the gallbladder (see Fig. 12B), with "dirty" acoustic shadowing that contains "comet tail" or "ring-down" artifacts. These

Cholecystitis Disease

Fig. 11. Gangrenous cholecystitis: imaging features. (A) Longitudinal sonogram shows membranes (arrowhead) and a shadowing stone (arrow) within the gallbladder lumen. (B) Coronal reformatted CT image shows marked mural thickening of the gallbladder, an intraluminal membrane (arrowhead), and pericholecystic inflammatory change extending to the hepatic flexure of the colon (arrow).

Fig. 11. Gangrenous cholecystitis: imaging features. (A) Longitudinal sonogram shows membranes (arrowhead) and a shadowing stone (arrow) within the gallbladder lumen. (B) Coronal reformatted CT image shows marked mural thickening of the gallbladder, an intraluminal membrane (arrowhead), and pericholecystic inflammatory change extending to the hepatic flexure of the colon (arrow).

artifacts must be differentiated from the WES sign of a contracted gallbladder filled with stones. Intramural gas manifests as a hyperechoic ring around the fluid-filled gallbladder. These features must be differentiated from shadowing that is secondary to a porcelain gallbladder or comet-tail artifacts that are due to cholesterol deposits within Rokitansky-Aschoff sinuses (RASs).62-66

Gallbladder Perforation

Some 5% to 10% of patients with acute cholecystitis develop gallbladder perforation.67 It occurs most commonly in the setting of gangrenous cholecystitis with other risk factors including gallstones, impaired vascular supply, infection, malignancy, and steroid use. The fundus of the gallbladder is the most common site of perforation because it has the most tenuous blood supply.68,69

Longitudinal Scan Gallbladder

Fig. 12. Emphysematous cholecystitis: imaging features. (A) Longitudinal sonogram shows intramural (solid arrows) and intraluminal (arrowhead) gas bubbles as well as debris (open arrow) within this necrotic gallbladder. (B) CT scan in the same patient shows intraluminal (solid arrow) and intramural (arrowhead) gas, as well as mural thickening of the gallbladder.

Fig. 12. Emphysematous cholecystitis: imaging features. (A) Longitudinal sonogram shows intramural (solid arrows) and intraluminal (arrowhead) gas bubbles as well as debris (open arrow) within this necrotic gallbladder. (B) CT scan in the same patient shows intraluminal (solid arrow) and intramural (arrowhead) gas, as well as mural thickening of the gallbladder.

Hemorrhagic Cholecystitis

This rare complication of acute cholecystitis results from hemorrhage secondary to mucosal ulceration and necrosis and has been reported in the presence and absence of gallstones. Atherosclerosis of the gallbladder wall is a major predisposing factor. Classically the patient presents with biliary colic, jaundice, and melena.2-4

On sonography, intraluminal blood appears as echogenic material with a higher echogenicity than sludge, which may form a dependent layer; however, blood clots may appear as clumps or masses adherent to the gallbladder wall. With evolving hemorrhage this may have a cystic appearance.70-73

On CTscan there is hyperdensity of the bile in addition to the other findings of acute cholecystitis. A fluid-fluid level may develop and if perforation occurs, hemoperito-neum may result. Prompt diagnosis is essential because hemorrhagic cholecystitis is associated with a high mortality rate.70,74-76

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Get Rid of Gallstones Naturally

Get Rid of Gallstones Naturally

One of the main home remedies that you need to follow to prevent gallstones is a healthy lifestyle. You need to maintain a healthy body weight to prevent gallstones. The following are the best home remedies that will help you to treat and prevent gallstones.

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