Unusual cases of acute cholecystitis and cholangitis: Tokyo Guidelines.

Unusual cases of acute cholecystitis and cholangitis include (1) pediatric biliary tract infections, (2) geriatric biliary tract infections, (3) acalculous cholecystitis, (4) acute and intrahepatic cholangitis accompanying hepatolithiasis (5) acute biliary tract infection accompanying malignant pancreatic-biliary tumor, (6) postoperative biliary tract infection, (7) acute biliary tract infection accompanying congenital biliary dilatation and pancreaticobiliary maljunction, and (8) primary sclerosing cholangitis. Pediatric biliary tract infection is characterized by great differences in causes from those of adult acute biliary tract infection, and severe cases should be immediately referred to a specialist pediatric surgical unit. Because biliary tract infection in elderly patients, who often have serious systemic conditions and complications, is likely to progress to a serious form, early surgery or biliary drainage is necessary. Acalculous cholangitis, which often occurs in patients with serious concomitant conditions, such as those in intensive care units (ICUs) and those with disturbed cardiac, pulmonary, and nephric function, has a high mortality and poor prognosis. Cholangitis accompanying hepatolithiasis includes recurrent pyogenic cholangitis, an epidemic disease in Southeast Asia. Biliary tract infections, which often occur after a biliary tract operation and treatment of the biliary tract, may have a fatal outcome, and should be carefully observed. The causes of acute cholangitis associated with pancreaticobiliary maljunction differ before and after operation. Direct cholangiography is most useful in the diagnosis of primary sclerosing cholangitis. If cholangiography visualizes a typical bile duct, differentiation from acute pyogenic cholangitis is easy. This article discusses the individual characteristics, diagnostic criteria, treatment guidelines, and prognosis of these unusual types of biliary tract infection.