Explanation
This patient's clinical presentation is suggestive of acalculous cholecystitis. This condition is most often seen in severely ill patients in the intensive care unit with multiorgan failure, severe trauma, surgery, burns, sepsis, or prolonged parenteral nutrition. Acalculous cholecystitis is likely due to cholestasis and gallbladder ischemia leading to secondary infection by enteric organisms and resultant edema and necrosis of the gallbladder. Most patients affected by this condition have no prior history of gallbladder disease.
Acalculous cholecystitis is a serious condition that can lead to sepsis and death if undetected. The clinical signs of disease (eg, fever, leukocytosis) are vague, and patients most vulnerable to this condition are typically non-communicative due to their general medical condition. The best way to make the diagnosis is a high degree of clinical suspicion and confirmation with imaging studies. Radiologic signs include gallbladder wall thickening and distension and the presence of pericholecystic fluid. The immediate treatment in critically ill patients includes antibiotics followed by percutaneous cholecystostomy under radiologic guidance. Cholecystectomy with drainage of any associated abscesses is the definitive therapy once the patient's medical condition improves.
Educational objective: Acalculous cholecystitis occurs in critically ill patients. The clinical presentation may be similar to calculous cholecystitis, though assessment may be difficult due to the underlying illness. Imaging studies show gallbladder wall thickening and distension and pericholecystic fluid. The emergency treatment of choice is antibiotics and percutaneous cholecystostomy, followed by cholecystectomy when the medical condition stabilizes.
(Choice B) Duodenal perforation usually presents with sudden-onset, diffuse abdominal pain. The abdomen is rigid on initial examination (becomes distended later) with signs of peritonitis. Imaging studies typically show free air under the diaphragm.
(Choice C) Mesenteric ischemia usually presents with sudden periumbilical abdominal pain out of proportion to examination findings. Risk factors include older age, atrial fibrillation, congestive heart failure, and atherosclerotic vascular disease. CT of the abdomen typically shows focal or segmental bowel wall thickening, small-bowel dilation, and mesenteric stranding.
(Choice D) Pancreatitis would not cause a distended gallbladder and pericholecystic fluid. CT findings of pancreatitis include parenchymal enhancement with intravenous contrast (in patients with no pancreatic necrosis), pseudocyst formation, or peripancreatic fluid collection.
(Choice E) Small-bowel obstruction is characterized by abdominal distension, high-pitched hyperactive bowel sounds, dilated loops of bowel with air-fluid levels on imaging, and no or minimal air in the colon and rectum. This patient's small- and large-bowel distension and hypoactive bowel sounds are more consistent with ileus (table below) due to his serious medical condition.
