Bile flows from the liver through the bile duct into the duodenum. Shortly before it opens into the bowel, at a small raised area of the bowel wall called the papilla, the duct usually meets the duct of the pancreas. Stones in the bile duct mostly come from the gallbladder and have migrated from there. Less often, they form in the duct itself, sometimes even years after gallbladder removal.
As long as a stone does not obstruct the flow, it often goes unnoticed. If it blocks it, bile backs up: the skin and eyes turn yellow, urine becomes dark and stools pale, often with pain in the upper abdomen and itching. Two consequences are serious – inflammation of the bile ducts with fever and chills, known as cholangitis, and inflammation of the pancreas if the stone is stuck in the papilla. Then prompt action is needed.
Ultrasound and blood tests provide the first clues: the blocked duct is widened, and bile and liver values rise. If doubts remain, endoscopic ultrasound or an MRI scan of the bile ducts (MRCP) clarifies whether there really is a stone. Today, ERCP is primarily a treatment procedure and is used when a stone has been confirmed or is very likely.
ERCP clears the duct while leaving the gallbladder untouched. If the gallbladder itself contains stones, new ones can slip down; this is why minimally invasive gallbladder removal usually follows, as soon as possible after the ERCP. Besides stones, ERCP also treats narrowings of the bile ducts, for example caused by scarring or tumours. After a gastric bypass, the route to the duodenum is diverted; gastroenterology and surgery then plan the access together.
Mamoon Al Hamed
Mohammad Al Rashdan
Dr. med. Barbara John, FEBGH
