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Emphysematous cholecystitis is a severe infectious form of acute cholecystitis. This condition typically occurs in the elderly, with a median age of 59. Additionally, 38% to 55% of affected patients have diabetes mellitus. These characteristics are consistent with the patient in this case.
Signs and symptoms are not significantly different from that observed in acute cholecystitis, and include right upper quadrant pain and fever. The condition is thought to occur when an ischemic gallbladder harbors gas-producing bacteria, such as Clostridium perfringens, which is seen in 33% of patients. Ischemia may result from arteriosclerosis, emboli, or from gallstone impaction and associated edema, causing vascular compromise.

Surgery is considered the mainstay of treatment. Antibiotics and fluid replacement are started immediately to stabilize the patient, but because of the risk of perforation and its impact on survival, clinicians tend to proceed to surgery as soon as possible. The overall mortality rates vary from 15-25%. These rates are 5 times the operative mortality rates for nonemphysematous cholecystitis.
Recently, interventional radiology techniques have been described that allow drainage and decompression followed by interval excision of the gallbladder. These techniques have been employed in patients with complications such as perforation and in those who have at high surgical risk. Ultimately, however, the gallbladder must be removed.

The classic appearance of emphysematous cholecystitis is inflammation and gas formation within gallbladder lumen and wall, which may extend to the pericholecystic tissues and extrahepatic ducts.
Emphysematous cholecystitis is a surgical emergency requiring urgent cholecystectomy. Overall, surgical mortality rates vary from 15-25%.
Pathology reveals acute necrotizing cholecystitis and cultures reveal Clostridium perfringens in 33% of patients.

Halpert, RD. Gastrointestinal Imaging: The Requisites. 3rd edition, Mosby, Philadelphia, 2006.
Brant and Helms. Fundamentals of Diagnostic Radiology. 3rd edition, Lippincott Williams and Wilkins, Philadelphia, 2006.
Bennett, GL et al: Ultrasound and CT evaluation of emergent gallbladder pathology. Radiol Clin North Am. 41(6):1203-16, 2003.
Yusoff IF et al: Diagosis and management of cholecystitis and cholangitis. Gastroenterol Clin North Am. 32(4):1145-68, 2003.