[Present status of hepatolithiasis in Japan]

Research Group for Hepatolithiasis, Ministry of Health and Welfare, Japanese Government surveyed cases of hepatolithiasis in the member hospitals. Total of 414 cases were collected between 1977 to 1981. They were divided according to the classification of hepatolithiasis proposed by Research Group for the Study of Damage to the Intrahepatic Bile Duct. Four hundred fifteen patients consisting of 186 males and 228 females. Female predominance was statistically significant (p less than 0.05). Age incidence rose rapidly at their thirties and reached the peak at their fifties. Most stones were calcium bilirubinate stones. In IE classification (intrahepatic and extrahepatic classification), they were equally distributed in each subtype. Left lobe predominated (L and LR Type) in hepatic lobe classification. Bile duct stenosis and dilatation were present in 57% and in 95% of the cases respectively. Bile duct stenosis occurred frequently in the left intrahepatic bile ducts. Possible etiological significance of IE classification difference from those confined to hepatic lobe (I type) to those predominantly in extrahepatic bile duct (IE type) were discussed.