Pathology of the gallbladder in common bile duct obstruction: the concept of ascending cholecystitis.

The presence of intraepithelial aggregates of neutrophils in the gallbladder mucosa is proposed as a specific histologic marker of common bile duct obstruction. Medical records of 334 patients who underwent cholecystectomy over a 14-month period were reviewed. Based on clinical, laboratory, radiologic, and operative findings, 48 patients with common duct obstruction were identified. Pathologic changes of acute cholecystitis were found in eight patients. In the remaining 40 patients the proposed pathognomonic changes of biliary obstruction were observed. Sensitivity and specificity of the histologic criterion were 83.3% and 97.4%, respectively. On a pathophysiologic basis, the characteristic inflammatory response in the gallbladder mucosa is believed to be analogous to the reaction seen in the wall of the common bile duct and liver, and a part of the process of ascending cholangitis. In the absence of usual changes of acute cholecystitis, a pathologist may suggest the possibility of common duct obstruction if intraepithelial neutrophilic aggregates are seen on examination of the gallbladder.