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What is Choledochal cysts and explain in detail?
Choledochal cysts (a.k.a. bile duct cyst) are congenital conditions involving cystic dilatation of bile ducts. 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, and a right upper quadrant abdominal 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. If the obstruction is not relieved, permanent damage may occur to the liver - scarring and cirrhosis - with the signs of portal hypertension  (obstruction to the flow of blood through the liver) and ascites (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)