What Is Choledocholithiasis?
Choledocholithiasis (also called bile duct stones or gallstones in the bile duct) is the presence of a gallstone in the common bile duct. Gallstones usually form in your gallbladder. The gallbladder is a pear-shaped organ below your liver in the upper-right side of your abdomen. These stones usually remain in the gallbladder or pass through the common bile duct unobstructed. The bile duct is the small tube that carries bile from the gallbladder to the intestine.
According to research published in the Medical Clinics of North America, approximately 15 percent of people who have gallstones develop choledocholithiasis. Of that 15 percent, an estimated five percent to 12 percent have primary bile duct stones (stones that are formed in the bile duct rather than in the gallbladder) (Attasaranya, et al., 2008).
What Causes Choledocholithiasis?
Gallstones often pass through the common bile duct unnoticed. However, about 15 percent of all people with gallstones will have gallstones in the bile duct.
There are two types of gallstones: cholesterol stones and pigment stones.
Scientists believe that cholesterol stones are caused by bile that contains:
- too much cholesterol
- too much bilirubin
- not enough bile salts
They may also occur if the gallbladder does not empty completely or often enough.
The cause of pigment stones is not known. They seem to occur in people who have:
- cirrhosis of the liver
- biliary tract infections
- hereditary blood disorders in which the liver makes too much bilirubin
Who is at Risk for Choledocholithiasis?
People with a history of gallstones or gallbladder disease are at risk for bile duct stones. Even people who have had their gallbladders removed can experience this condition.
Some of the risk factors for gallstones can be improved through lifestyle changes. The following increase your chances of developing gallstones:
- low-fiber, high-calorie, high-fat diet
- prolonged fasting
- rapid weight loss
- lack of physical activity
Risk factors you cannot change include:
- age: older adults typically have a higher risk for gallstones
- gender: women are more likely to have gallstones
- ethnicity: American Indians and Mexican-Americans are at higher risk for gallstones. Gallstones in the bile duct are more common in Asian populations
- family history: genetics may play a role
What Are the Symptoms of Choledocholithiasis?
Gallstones in the bile duct may not cause symptoms for months or even years. However, if the blockage becomes severe, you may experience the following:
- abdominal pain in the upper or middle-upper abdomen
- jaundice (yellowing of the skin and eyes)
- loss of appetite
- nausea and vomiting
When a gallstone is stuck in the bile duct, the bile can become infected. The bacteria from the infection can spread rapidly. It can move into the ductal system and then into the liver. It can become a life-threatening infection.
The pain caused by gallstones in the bile duct can be sporadic, or it can linger. The pain may also be mild at times and then suddenly severe. Severe pain may require emergency medical treatment. (The most severe symptoms are commonly confused with a cardiac event.)
If you have symptoms, a doctor will want to verify the presence of a gallstone in the common bile duct. He or she may use one of the following imaging tests:
- transabdominal ultrasound (TUS): an imaging procedure that uses high-frequency sound waves to examine the liver, gallbladder, spleen, kidneys, and pancreas
- abdominal CT scan: cross-sectional X-rays of the abdomen
- endoscopic ultrasound (EUS): an ultrasound probe is inserted on a flexible endoscopic tube and inserted through the mouth to examine the digestive tract
- endoscopic retrograde cholangiography (ERCP): a procedure used to identify stones, tumors, and narrowing in the bile ducts. An endoscopic tube is inserted through the mouth and dye is injected into the ducts where they can be visualized with X-rays.
- magnetic resonance cholangiopancreatography (MRCP): an MRI of the gallbladder, bile ducts, and pancreatic duct.
- percutaneous transhepatic cholangiogram (PTCA): an X-ray of the bile ducts
Your doctor may also order one or more of the following blood tests to look for an infection and to check liver and pancreas function:
- complete blood count
- pancreatic enzymes
- liver function tests
Treating gallstones in the bile duct focuses on relieving the blockage. These treatments may include:
- stone extraction
- fragmenting stones (lithotripsy)
- surgery to remove the gallbladder and stones (cholecystectomy)
- surgery that makes a cut into the common bile duct to remove stones or help them pass (sphincterotomy)
- biliary stenting
The most common treatment for gallstones in the bile duct is biliary endoscopic sphincterotomy (BES). During a BES procedure, a balloon- or basket-type device is inserted into the bile duct and used to extract the stone or stones. About 85 percent of bile duct stones can be removed with BES (Attasaranya et al., 2008).
If a stone does not pass on its own or cannot be removed with BES, doctors may use lithotripsy. This procedure is designed to fragment stones so they can be captured or passed easily.
Patients with gallstones in the bile duct and gallstones still in the gallbladder may be treated with cholecystectomy (gallbladder removal). While performing the surgery, your doctor will also inspect your bile duct to check for remaining gallstones.
If stones cannot be removed completely or you have a history of gallstones causing problems but do not wish to have your gallbladder removed, your doctor may place biliary stents (tiny tubes to open the passage). These will provide adequate drainage and help prevent future choledocholithiasis episodes. The stents can also prevent biliary sepsis (inflammation) and infection.
What Is the Long-Term Outlook?
According to a 2008 study published in Medical Clinics of North America, bile duct stones return in four to 24 percent of patients during the 15-year period after they first occur (Attasaranya et al, 2008.) However, some of these stones may have been left from the previous episode.
How Can Choledocholithiasis Be Prevented?
If you have bile duct stones once, it’s likely you will experience them again—unless you have your gallbladder removed, and even then, a risk remains.
Lifestyle changes such as moderate physical activity and dietary changes (increasing fiber and decreasing saturated fats) can reduce your likelihood of developing gallstones, which may reduce your risk of bile duct stones in the future.