Biliary infection: Cholecystitis and cholangitis

Infectious and inflammatory disorders of the gallbladder and bile ducts are referred to, respectively, as cholecystitis and cholangitis. Most of these disorders involve acute bacterial infections and can be quite serious or even life-threatening problems that require prompt diagnosis and treatment. This chapter discusses the pathogenesis, diagnosis, and current treatment of both acute cholecystitis and acute cholangitis. ACUTE CHOLECYSTITIS Acute cholecystitis refers to acute inflammation of the gallbladder. Ninety-eight percent of episodes of acute cholecystitis exhibit cystic duct obstruction on radionucleotide (hydroxy iminodiacetic acid; HIDA) scan, indicating that the process most often begins with obstruction of the cystic duct by a gallstone. In about 2% to 5% of cases termed acute acalculous cholecystitis, no gallstones are present, although some cases still exhibit obstruction of the cystic duct from fibrosis or edema. 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 leading to nonemptying of the gallbladder and stasis of bile in its lumen. A cascade of events triggered by gallstones, stasis, or cystic duct obstruction result in inflammation in the wall of the gallbladder, superinfection with bacteria, and eventually compromise of the gallbladder wall unchecked, gangrene of the gallbladder develops and perforation of the gallbladder with abscess formation or generalized perforation ensues.