Teaching Case

Admitted to hospital because of an asthmatic attack. Physical examination revealed severe splenomegaly and hepatomegaly. Laboratory tests revealed prothrombin time ratio of 61%, platelet count of 42.000/mm3, serum levels of total bilirubin and g GT of 1.9 mg/dl and 96 U/L, respectively. The patient underwent US and spiral CT examinations of the upper abdomen as well as MR cholangiography.

The caucasian patient was admitted to our hospital because of an asthmatic attack. Physical examination revealed severe splenomegaly and hepatomegaly. Laboratory tests revealed prothrombin time ratio of 61%, platelet count of 42.000/mm3, serum levels of total bilirubin and g GT of 1.9 mg/dl and 96 U/L, respectively. The patient underwent US and spiral CT examinations of the upper abdomen as well as MR cholangiography. Imaging findings: Abdominal US confirmed the presence of hepatomegaly and splenomegaly. Multiple cystic lesions, located in both hepatic lobes, were also seen (Fig.1a). Moreover, multiple microcysts and microstones located in the medulla of both kidneys were demonstrated (Fig 1b). Abdominal pre- and post-contrast spiral CT revealed multiple cystic lesions with internal central tiny septa, that showed contrast enhancement in the portal-venous phase (Fig 2a,b,c). Signs of portal hypertension were also present. Microcysts and microstones located in the medulla of the kidneys were confirmed (Fig 2d). MR cholangiography with maximum-intensity projection reconstruction displayed multiple cystic lesions communicating with intrahepatic bile ducts and containing central tiny septa. The appearance of the main bile duct and the hepatic ducts was normal. The insertion of the cystic duct into the main bile duct was located more inferior as typically seen (Fig 3).

Caroli’s disease is a congenital nonobstructive segmental cystic dilatation of intrahepatic bile ducts, involving completely or partially the biliary tree. Two primary types of the disease have been described: the so-called “pure” type (type I) and the more common type associated with congenital hepatic fibrosis (type II) (1-4,5). During the early embryologic development there is a single-layered ductal plate surrounding the portal vein followed by double-layered ductal plates and a slit-like primitive bile duct lumen. Extensive resorption of the primitive bile duct leads to the final stage consisting of a network of fine bile ducts surrounding the portal vein. In ductal plate malformation, insufficient resorption of ductal plates can cause large dilated segments of the primitive bile ducts surrounding the central portal vein (2). Histologic findings include irregular dilatation of bile ducts, complete and incomplete bridging of ductal walls and small portal branches in the center of the bile duct. In type II hepatic fibrosis is associated (1,2). Clinical presentation depends on to the complications, i.e. biliary stones, cholangitis, pericholangitic abscess, cholangiocellular carcinoma in type I; portal hypertension in type II (1). Caroli’s disease may be associated with autosomal recessive polycystic kidney disease, medullary sponge kidney and nephronophthisis (1). In our case diagnosis was suspected on the basis of spiral CT findings. Multiple cystic lesions with internal central tiny septa corresponding to portal vein branches and contrast enhancement in the portal-venous phase were seen. Diagnosis was established on the basis of MR cholangiography findings. Multiple cystic lesions communicating with intrahepatic bile ducts were delineated (Fig 3).