Sir,
We read with great interest the article on “Emphysematous Cholecystitis in 24-Year-old male without predisposing factors” by Sayit et al., [1] published in the July 2015 issue of the journal.
We would like to highlight few important points and differential diagnosis in this case for the readers.
The “Mercedes-Benz sign” describes a triradiate pattern of nitrogen gas within gallstones initially described on an abdominal radiograph and later in CT in cases of calculus cholecystitis as a cause of acute abdomen. Fissures, usually fluid-filled, are present in close to 50% of gallstones. Less than half of these fissured gallstones contain some amount of gas. The radiolucency caused by the gas usually appears in a triradiate pattern, mimicking the Mercedes-Benz logo [2]. In the case shown by the authors, this could very well be a case of Mercedes-Benz sign on CT. On imaging since air foci is not visualised in gallbladder bed on X-ray abdomen and fat/gas-attenuating nodular lesions are seen within the gallbladder, a close differential of cholesterol stones induced acute cholecystitis should be considered instead of directly labelling as emphysematous cholecystitis.
Authors’ Reply
First of all, I would like to thank you for the valuable contributions to our case report. Emphysematous cholecystitis is a severe form of acute cholecystitis and it occurrs frequently due to infection by gas producing organisms. We detected gas within the gallbladder lumen by computed tomography and that might be due to calculous cholecystitis or emphysematous cholecystitis. However, gas within the gallbladder lumen in our case cannot be described as triradiate pattern mimicking the Mercedes-Benz logo. Therefore, acute cholecystitis and emphysematous cholecystitis, induced by cholesterol stones, should be considered in the differential diagnosis in this case.
Thanks
Dr. Sayit AT
[1]. Sayit AT, Gunbey HP, Emphysematous Cholecystitis in 24-Year-old Male Without Predisposing Factors J Clin Diagn 2015 9:TD01-02. [Google Scholar]
[2]. Meyers MA, O’donohue N, The Mercedes-Benz sign: insight into the dynamics of formation and disappearance of gallstones Am J Roentgenol Radium Ther Nucl Med 1973 119:63-70. [Google Scholar]