<P> Murphy's sign is commonly negative on physical examination in choledocholithiasis, helping to distinguish it from cholecystitis . Jaundice of the skin or eyes is an important physical finding in biliary obstruction . Jaundice and / or clay - colored stool may raise suspicion of choledocholithiasis or even gallstone pancreatitis . If the above symptoms coincide with fever and chills, the diagnosis of ascending cholangitis may also be considered . </P> <P> Greater than 70% of people with gallstones are asymptomatic and are found incidentally on ultrasound . Studies have shown that 10% of those people will develop symptoms within five years of diagnosis and 20% within 20 years . </P> <P> While stones can frequently pass through the common bile duct (CBD) into the duodenum, some stones may be too large to pass through the CBD and may cause an obstruction . One risk factor for this is duodenal diverticulum . </P> <P> This obstruction may lead to jaundice, elevation in alkaline phosphatase, increase in conjugated bilirubin in the blood and increase in cholesterol in the blood . It can also cause acute pancreatitis and ascending cholangitis . </P>

Where do common bile duct stones come from
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