原発性コレステロール肝内結石症の1例

Primary Intrahepatic Cholesterol Gallstones, Report of a Case

要旨　患者は45歳男性で，主訴は心窩部痛，発熱，嘔吐．ERCPにて肝外胆管の拡張は認めなかったが，胆囊内に1個の胆石と肝左葉外下降枝に充満した多数の胆石像を認めた．血清脂質は正常であった．胆囊摘出術，総胆管切開ドレナージ，肝外側区域切除術を施行した．摘出胆石は胆囊結石は混成石，肝内結石は混合石であった．肝の組織学的検索では外下降枝は著しく蛇行し，胆管周囲には軽度の慢性炎症を認めたにすぎなかった．胆囊胆汁の脂質成分はコレステロール2.1mmol/l，燐脂質8.3mmol/l，総胆汁酸69.5mmol/lで催石指数は0.3であった．総胆管胆汁の催石指数も0.4であった．本症例の胆石の成因は従来のコレステロール溶存能に関する説明では理解できず，コレステロール結石生成の複雑さを考えさせた．

　The patient was a 45 year-old man with chief complaints of epigastralgia, fever and vomiting.

　ERCP showed one large radiolucent shadow in the gallbladder, and numerous in the lateral inferior area of the liver. However, no dilatation of the extrahepatic bile duct was seen. Serum lipid values were within normal limits. Cholecystectomy, choledochotomy with T-tube drainage and lateral segmentectomy were carried out. The large stone in the gallbladder was a combination stone, and those in the intrahepatic duct were mixed ones. Histological examination of the liver showed remarkable meander of the lateral inferior branch and slight grade pericholangitis. Lipid composition of the gallbladder bile was 2.1 mmol/l of cholesterol, 8.3 mmol/l of phospholipid, and 69.5 mmol/l of total bile acid, thus the lithogenic index of 0.3. Lithogenic index of the bile in the common duct was also 0.4.

　We couldn't explain the formation of the gallstone in this patient even if we had referred to the former explanation on cholesterol solubility and reconsidered the complexity of cholesterol stone formation.