45 - Biliary infection: cholecystitis and cholangitis

Summary

This chapter discusses the pathogenesis, diagnosis, and treatment of infections of the gallbladder and bile ducts. Bacterial disorders of the biliary tract range from simple colonization of bile with bacteria to serious, life-threatening problems requiring prompt diagnosis and treatment.

Acute cholecystitis

Acute cholecystitis is a common disorder manifest as acute inflammation of the gallbladder. Ninety-eight percent of episodes exhibit cystic duct obstruction, usually by a gallstone impacted in the gallbladder neck. Cystic duct obstruction results in nonvisualization of the gallbladder on technetium radionucleotide cholecintography (HIDA) scan. In 2% to 5% of cases, termed acute acalculous cholecystitis, gallstones are not present. Acute acalculous cholecystitis is most often found in debilitated or critically ill patients who have not been fed by mouth for extended periods of time, but acalculous cholecystitis also occurs in normal individuals. It is believed that stasis of bile in the gallbladder lumen leads to gallbladder wall inflammation in both calculous and acalculous cholecystitis. Bacteria play a secondary role as superinfection of bile with bacteria, and eventually gallbladder wall compromise, are later events (Figure 45.1). If unchecked, the process progresses to complicated cholecystitis with gangrene or perforation of the gallbladder. It is imperative that acute cholecystitis be diagnosed and effectively treated before life-threatening complications of acute cholecystitis ensue.