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.
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).