[Infected bile and intrahepatic gallstones]

Currently, the incidence of the upper stenotic type and intrahepatic stenotic type have been increasing in number. These changes may be attributed to the improvements of the diagnostic tools for hepatobiliary diseases, especially in the progress of imaging methods. In view of the type of gallstone, most intrahepatic gallstones are the calcium bilirubinate stones generated on the basis of bile stasis and bacterial infection. For the formation of calcium bilirubinate stones the mutual relationship of bacterial beta-glucuronidase and glucaro-1, 4-lactone in the bile is thought to important. Free bile acids and fatty acids are detected in fairly large amount in calcium bilirubinate stones. This suggests that precipitation of calcium bilirubinate in the bile may coincidently occur with the deconjugation of the conjugated bile acids and decomposition of lecithin. In the formation of calcium bilirubinate stones, it is believed that diet and bacterial infection accompanying biliary stasis are important inducements. Since these stones are formed mainly in bile ducts and recurrence rates are likely to high, it is important to remove these inducements from therapeutic viewpoint.