Pathophysiologic mechanisms in patients with cholangitis or obstructive jaundice: Results of a cholangiographic study

Bacterial reflux from the biliary tract to the systemic circulation is considered to be the primary etiologic factor in bacteremia and the development of sepsis. However, as the pathophysiologic features of the biliary tract that may promote such a reflux of biliary bacteria remain unclear, we investigated, using direct cholangiography, the pathophysiologic relationship between the intrahepatic bile ducts and biliary reflux into the systemic circulation after the percutaneous infusion of a contrast material containing indocyanine green (ICG) into the circulating blood. The subjects were 19 patients who underwent percutaneous transhepatic cholangiography with drainage to treat either a biliary infection or obstructive jaundice, an 8 post‐T‐tube control patients with normal biliary drainage. The relationship between the biliary tract pressure and ICG reflux during cholangiography was also analyzed. An ICG reflux was observed in all 19 patients who had undergone percutaneous transhepatic cholangiography with drainage and in 2 of the 8 control patients. In all patients who showed positive ICG reflux, this occurred when the biliary pressure increased to 25cm H2O. An ICG reflux was seen in the 16 patients with a positive bile culture, and in 7 of 13 patients with a negative bile culture. When we analyzed ICG reflux in relation to the morphology of the intrahepatic bile duct, we found that all 4 patients who had cholangitic hepatic abscesses also exhibited higher ICG reflux concentrations and the clinical symptoms of cholangitis. Radiologically, all 7 patients with cholangitis demonstrated many small intrahepatic branches, and they exhibited moderate ICG refluxes, whereas the 6 patients who had obstructive jaundice but no cholangitis had fewer ICG refluxes and no clinical symptoms. This study demonstrated two possible pathophysiological routes for biliary reflux: (1) via cholangitic hepatic abscesses, with entry of the bacteria directly into the circulating blood, or (2) via the small intrahepatic biliary branches, in which entry of bacteria into the systemic circulation occurs through the cholangioles.