Duodenal Ulcer Perforation Causing Acute Cholecystitis.

Acute cholecystitis is an inflammatory condition of the gallbladder, characterized by infection, ulceration, and neutrophilic infiltration of the gallbladder wall. Approximately 90% of cases are caused by gallstones. In contrast, acalculous cholecystitis is defined as the inflammation of the gallbladder in the absence of gallstones during diagnosis. The causes of acalculous cholecystitis include impaired blood flow to the gallbladder, chemical injury, bacterial or parasitic infections, and collagen vascular diseases. However, in this case, it was caused by an extremely rare condition: a duodenal ulcer penetration. Physical examination, blood tests, and ultrasound suggested a diagnosis of acute cholecystitis. However, contrast-enhanced CT showed no gallstones and revealed a partial mucosal defect in the first portion of the anterior duodenum. There was also wall thickening and increased density of the surrounding fat tissue, particularly around the gallbladder wall adjacent to the first portion of the anterior duodenum. Based on these findings, secondary cholecystitis due to perforation of a duodenal ulcer was diagnosed, and laparoscopic cholecystectomy with omental patching was performed. Although rare, a duodenal ulcer should be considered as a cause of acalculous cholecystitis.