What is Choledocholithiasis?
Choledocholithiasis is a medical condition where there are stones in the common bile duct. This tube carries digestive fluid, known as bile, from your liver to your gallbladder and intestines. These stones are found in about 1-15% of people who have gallstones. The primary treatment for these bile duct stones is a procedure called endoscopic retrograde cholangiopancreatography (ERCP). In some circumstances, a surgical procedure known as laparoscopic cholecystectomy with bile duct exploration might be performed. In most medical centers in the US, if someone has bile duct stones, they usually have an ERCP procedure followed by a laparoscopic cholecystectomy, which is a less invasive surgery to remove the gallbladder.
What Causes Choledocholithiasis?
Choledocholithiasis is a condition where stones form in the common bile duct or when gallstones from the gallbladder move into the same duct. Many factors can cause these stones such as blocked bile, bacteria, chemical imbalances, excess bilirubin, pH imbalances, or the creation of sludge. Sometimes, stones can form in the liver’s biliary tree, known as primary hepatolithiasis, which can also lead to choledocholithiasis.
Stones that are too big to pass through the ampulla of Vater, a place where bile and pancreatic ducts meet, remain in the lower common bile duct. This blockage may cause obstructive jaundice, potentially leading to conditions like pancreatitis, hepatitis, or cholangitis.
Gallstones are differentiated by their composition. Cholesterol stones are chiefly made of cholesterol, while black pigment stones are chiefly made of pigment, and brown pigment stones are a mix of pigment and bile lipids. Approximately 75% of the secondary common bile duct stones in the United States are cholesterol stones, while black pigment stones make up the rest. The primary common bile duct stones are typically brown pigment stones.
When the common bile duct gets blocked by gallstones, it can result in several symptoms and complications, including pain, jaundice, and sepsis.
Risk Factors and Frequency for Choledocholithiasis
Choledocholithiasis, or stones in the common bile duct, are found in roughly 4.6% to 18.8% of patients having their gallbladder removed. This condition becomes more common as patients with gallstones get older. Gallstones, or cholelithiasis, are more common in women, people who are pregnant, older individuals, and those with high levels of fats in their blood.
- Cholesterol stones are typically seen in people who are overweight, have given up physical activity, or have recently lost weight on purpose.
- Black pigment stones are common in people with cirrhosis, those receiving nutrition intravenously, and those who have had a portion of their small intestine removed.
- Brown pigment stones in the common bile duct mainly come from bacteria, which act as a catalyst for the formation of these stones.
Signs and Symptoms of Choledocholithiasis
When a healthcare provider is treating a patient, they need to ask detailed questions about any abdominal pain that the patient is experiencing. This includes understanding how sudden the pain started, how bad it is, and whether the patient has had similar pain in the past. This type of pain is usually spasmodic and located in the top right area of the belly. The pain tends to come and go and is of medium severity. Often, a patient may have faced similar episodes of stomach or upper right belly pain in the past.
Continuing the examination, the doctor may find that the patient’s eyes or skin have turned yellow, a condition known as jaundice. This happens when gallstones block the common bile duct and a substance known as conjugated bilirubin enters the bloodstream. Patients may have light-colored stools and dark-colored urine. They may have also experienced itching, nausea, or vomiting in the past. All these symptoms may go through phases of coming and disappearing.
Patients suffering from a condition known as cholangitis may show additional symptoms like fever, chills, and confusion. It is also noteworthy that gallstones are responsible for causing pancreatitis in about half of the cases. This condition occurs when the blockage is at the ampulla of Vater (the opening that leads to the pancreas). In such as case, the pain is persistent and localized to the mid-section of the belly and upper stomach area, differs from the intermittent pain caused by gallstones. This pain also spreads to the patient’s back, and they may also experience nausea and vomiting. Some patients may face recurring pain episodes due to temporary blockages in the common bile duct caused by floating stones or debris.
In the physical examination, the healthcare provider also inspects the patient’s general appearance, skin, vital signs, and belly. They may find tenderness in the upper right side of the patient’s belly. Other warning signs that could indicate a serious condition include fever, low blood pressure, and flushed skin. The physician may also find a palpable gallbladder upon examination- it suggests that the gallbladder has swelled due to a blockage of the common bile duct. Other parameters for which the physician is on watch are high body temperature, excessive sweating, jaundice, discolored white part of the eye, fast heart rate, low blood pressure, rapid breathing, or tenderness in the upper right belly.
Testing for Choledocholithiasis
If a patient might have choledocholithiasis, a condition involving gallstones in the bile duct, the doctor will order several tests. These include a white blood cell count, a test to measure the amount of hemoglobin (a protein that carries oxygen) and hematocrit (the proportion of red blood cells to the total blood volume) in your blood, a platelet count (to measure how many platelets, which aid in blood clotting, are in your blood), and tests to measure levels of certain enzymes and proteins in your blood like total bilirubin, direct bilirubin, alkaline phosphatase, aspartate aminotransferase, and alanine aminotransferase.
For patients with gallstones, high total bilirubin levels (over 3-4mg per dL of blood) are a strong sign of having choledocholithiasis. Levels of other substances like the enzymes gamma-glutamyl transpeptidase, alanine aminotransferase, and aspartate aminotransferase in your blood can also increase if there’s a blockage in the bile duct. However, elevated liver tests don’t necessarily mean you have choledocholithiasis because other factors can also cause them to rise. If these levels are normal, it can help rule out choledocholithiasis. If a patient’s symptoms improve and these levels go down, it could indicate that a gallstone has passed naturally.
As part of the investigation, the doctor may order a lipase test to check for gallstone pancreatitis and an INR with prothrombin time to assess liver function.
For imaging, a transabdominal ultrasound is usually the first one ordered. It can show if the common bile duct (the tube that carries bile from the liver and gallbladder to the small intestine) is dilated (more than 6mm wide) or if there are stones in it. However, it’s difficult for this test to identify stones in the common bile duct because gas in the duodenum (the first part of the small intestine) can block the view. Ultrasound can accurately detect a dilated common bile duct up to 90% of the time but is only 15-40% sensitive in detecting stones in it. If the ultrasound doesn’t reveal stones, but other signs point to choledocholithiasis, a doctor may order a magnetic resonance cholangiopancreatography (MRCP). This is a type of MRI that can provide a detailed view of the biliary and pancreatic systems. It is very accurate, with 92% sensitivity and 100% specificity.
If these tests don’t provide a clear answer, an endoscopic ultrasound may be ordered. This involves inserting an ultrasound probe into the duodenum to get a closer look at the biliary system. This test is more invasive but can detect stones in the common bile duct with 85-100% accuracy.
Lastly, if a patient is having surgery to remove the gallbladder, the surgeon can do an intraoperative cholangiogram. This involves injecting a contrast material into the cystic duct (the duct that connects the gallbladder to the common bile duct) and then taking x-ray images. This offers an outline of the biliary tree and helps identify any gallstones. However, this technique depends on the surgeon’s skill level, and not all general surgeons perform it routinely.
Treatment Options for Choledocholithiasis
Choledocholithiasis, which refers to having stones in the common bile duct, is typically treated by removing the stones using an endoscopic procedure. This procedure, known as an ERCP, involves a doctor inserting a specialized scope into the small intestine to access the bile duct. A tiny device is then used to cut a small opening to the bile duct, allowing the stones to be released and removed. Sometimes, a stent or tube is placed in the bile duct to assist with drainage and to make it easier to remove any remaining stones.
This procedure can usually be done while the patient is under general anesthesia, with the most common position being laying on their stomach. If certain conditions are met, like the stones being too large, numerous, or firmly lodged, a surgical procedure may be necessary to remove them. At the same hospital admission, removing the gallbladder, or a cholecystectomy, might also be suggested to prevent future episodes of choledocholithiasis.
Still, there’s ongoing debate about the need for cholecystectomy in patients with choledocholithiasis. Those with severe health concerns or older age might not be recommended for surgery, particularly if their gallbladder isn’t causing any symptoms.
In cases where the stones are primarily in the bile duct, cholecystectomy isn’t typically recommended. Instead, other surgical choices are available, like open bile duct surgery, a technique to clear the bile duct during laparoscopic cholecystectomy, non-surgical extraction, and shock wave therapy to break up the stones.
If the stones are discovered during a surgery for gallstones or gallbladder inflammation, the doctor might choose to remove the stones during the operation. Alternatively, an ERCP can be done at a later point during the same hospital stay.
There are currently no known drugs that can cure choledocholithiasis. However, a one-time dose of indomethacin can be employed to prevent inflammation of the pancreas if the pancreatic duct was manipulated during an ERCP. Antibiotics are typically not needed for choledocholithiasis, unless it’s accompanied by gallbladder inflammation or bile duct infection.
What else can Choledocholithiasis be?
When a doctor is trying to diagnose choledocholithiasis, several conditions might be considered due to their similar symptoms:
- Bile duct cancer
- Klatskin tumor (a specific type of bile duct cancer)
- Bile duct stricture (a narrowing of the bile duct)
- Choledochal cyst (a fluid-filled sac in the bile duct)
- Peptic ulcer disease (sores in the lining of the stomach or first part of small intestine)
- Acute cholecystitis (inflammation of the gallbladder)
- Sphincter of Oddi dysfunction (a problem with the valve that controls the flow of digestive juices to the first part of the small intestine)
- Functional gallbladder disorder (abnormal gallbladder function without stones).
The doctor has to carefully consider these conditions and do the necessary tests to make sure the diagnosis is accurate.
What to expect with Choledocholithiasis
The outlook for people with choledocholithiasis, or bile duct stones, strongly depends on whether they have complications and how severe these complications are. About half the patients with this condition (45%) don’t show any symptoms, while others may experience various complications. Specifically, 55% of patients who can’t have surgery or choose not to might face different degrees of complications.
Interestingly, less than 20% of people might have a recurrence of symptoms even after undergoing treatment. But overall, if treatment is started at the right time, typically the outlook is good for most people with this condition.
Possible Complications When Diagnosed with Choledocholithiasis
Treating Choledocholithiasis, a condition involving stones in the bile duct, can lead to a number of complications, such as:
- Inflammation of the pancreas after ERCP (a medical procedure)
- Sepsis, a life-threatening infection
- Wound infections
- Cholangitis, an infection of the bile duct
- Stones getting stuck or left in the bile duct
- Pancreatitis caused by gallstones
- Respiratory insufficiency, a condition where the body doesn’t get enough oxygen
- Injury to the biliary duct, the pathway for bile flow
- Renal failure, where the kidneys stop working properly
- Liver failure and cirrhosis, or scarring of the liver
- Injury to the liver’s blood vessels
Preventing Choledocholithiasis
Choledocholithiasis refers to the condition of having gallstones in the duct that carries bile from the liver to the small intestine, known as the common bile duct. One of its main symptoms is pain in the upper right section of the belly. The pain can vary in intensity and timing from one person to another. Often, eating food high in fat can lead to this pain because it triggers the gallbladder to contract. Yet, in many cases, the pain can also occur at night.
On the other hand, acute cholangitis is a condition marked by fever, yellowing of the skin (jaundice), and belly pain. It is caused by an infection that occurs when the biliary system, which carries bile, gets blocked.
The best treatment option for these conditions depends on several factors. These include the size of the gallstones, whether or not the patient is experiencing symptoms, and the patient’s opinion of different treatment possibilities.