How can you explain the US findings?
GB wall oedema, hyperaemia and maximal tenderness indicate acute cholecystitis, however the GB is not obstructed. Not all cases of acute acalculous cholecystitis affect critically ill patients in a hospital setting. Bacterial or viral infection can spread to the GB through bile or blood causing acute cholecystitis, in this case most likely due to Salmonella enteritis.
Oedematous, hyperaemic, thick-walled gall bladder containing dependent sludge but no calculi. The cystic duct is clearly seen and is patent. The gall bladder is full but compressible. Maximum tenderness to transducer pressure over the gall bladder (positive Murphy’s sign). Minor peri-cholecystic fluid. Trace ascites near the inferior angle of the liver.