Applied Radiology

Diagnosis

Emphysematous cholecystitis.

Findings

Supine and and left lateral decubitus abdominal views demonstrate an abnormality in the right upper quadrant, characterized as a mixed density oval shaped structure, with a surrounding rim of gas. Note a self-expanding metallic biliary stent.

Discussion

Emphysematous cholecystitis is a relatively rare manifestation of acute cholecystitis, caused by a gas producing organism. Most common pathogens include clostridial, staphylococcal, and streptococcal pathogens. Culture in this case grew out Clostridium perfringens. Classically associated with diabetes mellitus, emphysematous cholecystitis may also manifest in debilitated patients, including patients receiving chemotherapy and radiation therapy. The disease is most commonly associated with calculus cystic duct obstruction, although acalculous disease has also been reported. Symptoms are classically identical to acute cholecystitis, including focal right upper quadrant tenderness, fever, and leukocytosis. Note, however, that abdominal pain may be mild and/or leukocytosis may be absent, especially in elderly and diabetic patients. As in this case, plain films demonstrate gas within the gallbladder wall, outlining the gallbladder contour. Intraluminal gas and air-fluid levels may be present within the gallbladder lumen. Calcified or cholesterol gallstones may be visible. Ultrasound demonstrates linear or arcuate shadowing, often obscuring the gallbladder lumen. Obviously, computed tomography most clearly delineates these abnormalities, as well as associated abnormalities, such as a perforation. Timely diagnosis and treatment is necessary, as emphysematous cholecystitis carries a high mortality rate is (~20%).

Dahnert W. Radiology Review Manual. Lippincott Williams and Wilkins, Philadelphia, 2003. Bloom A, Remy P. Emphysematous cholecystitis. eMedicine (last updated 6/27/05).