Caroli disease (communicating cavernous ectasia, or congenital cystic dilatation of the intrahepatic biliary tree) is a rare inherited disorder characterized by cystic dilatation (or ectasia) of the bile ducts within the liver. There are two patterns of Caroli disease: focal or simple Caroli disease consists of abnormally widened bile ducts affecting an isolated portion of liver. The second form is more diffuse, and when associated with portal hypertension and congenital hepatic fibrosis, is often referred to as "Caroli syndrome". The underlying differences between the two types are not well understood. Caroli disease is also associated with liver failure and polycystic kidney disease. The disease affects about one in 1,000,000 people, with more reported cases of Caroli syndrome than of Caroli disease.
Caroli disease is distinct from other diseases that cause ductal dilatation caused by obstruction, in that it is not one of the many choledochal cyst derivatives. Caroli disease usually occurs in the presence of other diseases, such as autosomal recessive polycystic kidney disease, cholangitis, gallstones, biliary abscess, sepsis, liver cirrhosis, kidney failure, and cholangiocarcinoma (7% affected). These morbid conditions often prompt the diagnosis. Portal hypertension may be present, resulting in other conditions including enlarged spleen, hematemesis, and melena.
Causes
[[File:Pkhd1 gene.jpeg|right|thumb|
Figure 2 Location of the PKHD1 gene on chromosome 6, short (p) arm
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The cause appears to be genetic; the simple form is an autosomal dominant trait, while the complex form is an autosomal recessive trait. Family history may include kidney and liver disease due to the link between Caroli disease and ARPKD. PKHD1, the gene linked to ARPKD, has been found mutated in patients with Caroli syndrome. PKHD1 is expressed primarily in the kidneys with lower levels in the liver, pancreas, and lungs, a pattern consistent with phenotype of the disease, which primarily affects the liver and kidneys. Commonly, the disease is limited to the left lobe of the liver. Images taken by CT scan, X-ray, or MRI show enlarged intrahepatic (in the liver) bile ducts due to ectasia. Using an ultrasound, tubular dilation of the bile ducts can be seen. On a CT scan, Caroli disease can be observed by noting the many fluid-filled, tubular structures extending to the liver. However, cholangiography is the best, and final, approach to show the enlarged bile ducts as a result of Caroli disease.
Treatment
The treatment depends on clinical features and the location of the biliary abnormality. When the disease is localized to one hepatic lobe, hepatectomy relieves symptoms and appears to remove the risk of malignancy. Good evidence suggests that malignancy complicates Caroli disease in roughly 7% of cases.
Family studies are necessary to determine if Caroli disease is due to inheritable causes. Regular follow-ups, including ultrasounds and liver biopsies, are performed.
Prognosis
Mortality is indirect and caused by complications. After cholangitis occurs, patients typically die within 5–10 years.
He described it as "nonobstructive saccular or fusiform multifocal segmental dilatation of the intrahepatic bile ducts"; basically, he observed cavernous ectasia in the biliary tree causing a chronic, often life-threatening hepatobiliary disease.
Caroli, born in France in 1902, learned and practiced medicine in Angers. After World War II, he was chief of service for 30 years at Saint-Antoine in Paris. Before dying in 1979, he was honored with the rank of commander in the Legion of Honour in 1976.