Choledochal cysts (a.k.a. bile duct cyst) are

congenital A birth defect, also known as a congenital disorder, is an abnormal condition that is present at birth regardless of its cause. Birth defects may result in disabilities that may be physical, intellectual, or developmental. The disabilities can ...

conditions involving

cyst A cyst is a closed sac, having a distinct envelope and cell division, division compared with the nearby Biological tissue, tissue. Hence, it is a cluster of Cell (biology), cells that have grouped together to form a sac (like the manner in which ...

ic dilatation of

bile ducts A bile duct is any of a number of long tube-like structures that carry bile, and is present in most vertebrates. Bile is required for the digestion of food and is secreted by the liver into passages that carry bile toward the hepatic duct. It ...

. They are uncommon in western countries but not as rare in East Asian nations like Japan and China.

Signs and symptoms

Most patients have symptoms in the first year of life. It is rare for symptoms to be undetected until adulthood, and usually adults have associated complications. The classic triad of intermittent abdominal pain,

jaundice Jaundice, also known as icterus, is a yellowish or greenish pigmentation of the skin and sclera due to high bilirubin levels. Jaundice in adults is typically a sign indicating the presence of underlying diseases involving abnormal heme meta ...

, and a

right upper quadrant The human abdomen is divided into quadrants and regions by anatomists and physicians for the purposes of study, diagnosis, and treatment. The division into four quadrants allows the localisation of pain and tenderness, scars, lumps, and other ...

abdominal mass An abdominal mass is any localized enlargement or swelling in the human abdomen. Depending on its location, the abdominal mass may be caused by an enlarged liver (hepatomegaly), enlarged spleen (splenomegaly), protruding kidney, a pancreatic mass, ...

is found only in minority of patients. In infants, choledochal cysts usually lead to obstruction of the bile ducts and retention of bile. This leads to jaundice and an

enlarged liver Hepatomegaly is the condition of having an enlarged liver. It is a non-specific medical sign having many causes, which can broadly be broken down into infection, hepatic tumours, or metabolic disorder. Often, hepatomegaly will present as an abdomi ...

. If the obstruction is not relieved, permanent damage may occur to the liver - scarring and

cirrhosis Cirrhosis, also known as liver cirrhosis or hepatic cirrhosis, and end-stage liver disease, is the impaired liver function caused by the formation of scar tissue known as fibrosis due to damage caused by liver disease. Damage causes tissue repai ...

- with the signs of

portal hypertension Portal hypertension is abnormally increased portal venous pressure – blood pressure in the portal vein and its branches, that drain from most of the intestine to the liver. Portal hypertension is defined as a hepatic venous pressure gradient gr ...

(obstruction to the flow of blood through the liver) and

ascites Ascites is the abnormal build-up of fluid in the abdomen. Technically, it is more than 25 ml of fluid in the peritoneal cavity, although volumes greater than one liter may occur. Symptoms may include increased abdominal size, increased weight, ab ...

(fluid accumulation in the abdomen). There is an increased risk of cancer in the wall of the cyst. In older individuals, choledochal cysts are more likely to cause abdominal pain and intermittent episodes of jaundice and occasionally cholangitis (inflammation within the bile ducts caused by the spread of bacteria from the intestine into the bile ducts). Inflammation of the pancreas also may occur. The cause of these complications may be related to either abnormal flow of bile within the ducts or the presence of gallstones.

Diagnosis

Direct

hyperbilirubinemia Bilirubin (BR) (Latin for "red bile") is a red-orange compound that occurs in the normal catabolic pathway that breaks down heme in vertebrates. This catabolism is a necessary process in the body's clearance of waste products that arise from the ...

Types

They were classified into 5 types by Todani in 1977. Classification was based on site of the cyst or dilatation. Type I to IV has been subtyped. * Type I: Most common variety (80-90%) involving saccular or fusiform dilatation of a portion or entire

common bile duct The common bile duct, sometimes abbreviated as CBD, is a duct in the gastrointestinal tract of organisms that have a gallbladder. It is formed by the confluence of the common hepatic duct and cystic duct and terminates by uniting with pancreati ...

(CBD) with normal

intrahepatic duct Intrahepatic bile ducts compose the outflow system of exocrine bile product from the liver. They can be divided into: * Lobar ducts (right and left hepatic ducts) - stratified columnar epithelium. * Interlobar ducts (between the main hepatic ...

. * Type II: These cysts are present as an isolated diverticulum protruding from the CBD. * Type III or Choledochocele: Arise from dilatation of duodenal portion of CBD or where

pancreatic duct The pancreatic duct, or duct of Wirsung (also, the major pancreatic duct due to the existence of an accessory pancreatic duct), is a duct joining the pancreas to the common bile duct. This supplies it with pancreatic juice from the exocrine pancre ...

meets. * Type IVa: Characterized by multiple dilatations of the intrahepatic and extrahepatic

biliary tree The biliary tract, (biliary tree or biliary system) refers to the liver, gallbladder and bile ducts, and how they work together to make, store and secrete bile. Bile consists of water, electrolytes, bile acids, cholesterol, phospholipids and co ...

. * Type IVb: Multiple dilatations involving only the extrahepatic bile ducts. * Type V: Cystic dilatation of intrahepatic biliary ducts without extrahepatic duct disease. The presence of multiple saccular or cystic dilations of the intrahepatic ducts is known as

Caroli's disease 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 patter ...

. * Type VI: An isolated cyst of the cystic duct is an extremely rare lesion. Only single case reports are documented in the literature. The most accepted classification system of biliary cysts, the Todani classification, does not include this lesion. Cholecystectomy with cystic duct ligation near the common bile duct is curative.

Treatment

Choledochal cysts are treated by surgical excision of the cyst with the formation of a

roux-en-Y anastomosis In general surgery, a Roux-en-Y anastomosis, or Roux-en-Y, is an end-to-side surgical anastomosis of bowel used to reconstruct the gastrointestinal tract. Typically, it is between stomach and small bowel that is distal (or further down the ...

hepaticojejunostomy/ choledochojejunostomy to the

biliary duct A bile duct is any of a number of long tube-like structures that carry bile, and is present in most vertebrates. Bile is required for the digestion of food and is secreted by the liver into passages that carry bile toward the hepatic duct. It ...

. Future complications include cholangitis and a 2% risk of malignancy, which may develop in any part of the biliary tree. A recent article published in the Journal of Surgery suggested that choledochal cysts could also be treated with single-incision laparoscopic hepaticojejunostomy with comparable results and less scarring. In cases of saccular type of cyst, excision and placement of T-shaped tube is done. Currently, there is no accepted indication for fetal intervention in the management of prenatally suspected choledochal cysts.

References

External links

{{Congenital malformations and deformations of digestive system Biliary tract disorders Congenital disorders of digestive system