Choledocholithiasis is the presence of stones within the common bile duct. It is estimated that common bile duct stones are present in anywhere from 1-15% of patients with cholelithiasis. The present-day treatment of bile duct stones is endoscopic retrograde cholangiopancreatography (ERCP) or in some cases a laparoscopic cholecystectomy with bile duct exploration. In most US centers, when bile duct stones present, ERCP is usually followed with a laparoscopic cholecystectomy.
Gallstones may pass from the gallbladder into the cystic duct, and then the common bile duct spontaneously. These stones are known as secondary bile duct stones. Less commonly, stones are formed in the intrahepatic biliary tree, termed primary hepatolithiasis, and may lead to choledocholithiasis. Stones that are too large to pass through the ampulla of Vater remain in the distal common bile duct, causing obstructive jaundice that may lead to pancreatitis, hepatitis, or cholangitis. Cholesterol stones make up approximately 75% of the secondary common bile duct stones in the United States, while black pigment stones comprise the remainder. Primary common bile duct stones are usually brown pigment stones.
Choledocholithiasis has been found in 4.6% to 18.8% of patients undergoing cholecystectomy. The incidence of choledocholithiasis in patients with cholelithiasis increases with age. Cholelithiasis is more common in female patients, pregnant patients, older patients, and those with high serum lipid levels. Cholesterol stones are typically found in obese patients with low physical activity or patients that have recently intentionally lost weight. Black pigment stones are found in patients with cirrhosis, patients receiving total parental nutrition, and in those who have undergone an ileal resection. Nucleating factors, such as bacteria, are the source of the brown pigment primary common bile duct stones.
Bile made in the liver and stored in the gallbladder can lead to gallstone formation. In some patients with gallstones, the stones will pass from the gallbladder into the cystic duct and then into the common bile duct. Less common sources of choledocholithiasis include complicated Mirizzi syndrome or hepatolithiasis. Bile flow is obstructed by stones within the common bile duct, which leads to obstructive jaundice and possibly hepatitis. The stagnant bile can also lead to bactibilia and ascending cholangitis. Cholangitis and sepsis are more common in patients with choledocholithiasis than other sources of bile duct obstruction because a bacterial biofilm typically covers common bile duct stones. The pancreatic duct joins the common bile duct near the duodenum, and therefore, the pancreas may also become inflamed by the obstruction of pancreatic enzymes. This is termed gallstone pancreatitis.
The treating provider must assess the patient by conducting a thorough history and physical. This includes asking about the onset, timing, and severity of the patient's abdominal pain, in addition to any previous occurrences of similar pain. Often, patients will endorse a history of episodes of epigastric or right upper quadrant pain or epigastric pain. A thorough review of systems will reveal that the patient may have noticed a yellowing of his eyes or skin, experienced pruritus, and possibly nausea or vomiting. A patient with cholangitis also may have fevers and chills and possibly altered mental status (Charcot triad or Reynolds pentad). The provider should examine the patient with particular attention to the general appearance, skin, vital signs, and abdomen. Note should be made for any hyperthermia, diaphoresis, jaundice, scleral icterus, tachycardia, hypotension, tachypnea, or right upper quadrant abdominal tenderness.
The provider should order a white blood cell count, hemoglobin/hematocrit, platelet count, total bilirubin, direct bilirubin, alkaline phosphatase, aspartate aminotransferase, and alanine aminotransferase. In a patient with cholelithiasis, a total bilirubin of greater than 3 mg/dL to 4 mg/dL is strongly associated with choledocholithiasis. Gamma-glutamyl transpeptidase also will be elevated. A lipase also should be checked to assess for gallstone pancreatitis. An INR with prothrombin time can be ordered to assess the intrinsic liver function as well. An abdominal ultrasound is the first test that should be ordered for the patient suspected of any biliary disease, including choledocholithiasis. In most cases, an abdominal ultrasound will show a dilated common bile duct (more than 6 mm) and stones within the common bile ducts. If a strong suspicion still exists based on history, physical, and laboratory findings in the face of a negative ultrasound, then a magnetic resonance cholangiopancreatography (MRCP) can be ordered. Endoscopic ultrasound also can be used to identify suspected choledocholithiasis, but it is more invasive than a transabdominal ultrasound or MRCP. Although diagnostic endoscopic retrograde cholangiopancreatography (ERCP) is more sensitive, it is no longer routinely performed given the approximately 10% risk for post-procedure pancreatitis.
If a patient is undergoing a laparoscopic or open cholecystectomy, an intraoperative cholangiogram also can be performed to assess for choledocholithiasis. Intraoperative ultrasound or laparoscopic ultrasound will also identify choledocholithiasis. However, this technique is operator dependent, and not commonly performed by general surgeons.
The treatment for choledocholithiasis is the removal of the obstructing stones, via endoscopic means. An ERCP can be performed under general anesthesia, with the patient in either prone, left lateral, or supine position, though prone is the most common position used. The endoscopist will then place a duodenoscope into the second portion of the duodenum and advance a catheter and guidewire into the common bile duct. An autotome or sphincterotome then is used to cut the papilla, using cautery, and enlarge the ampulla of Vater. Often, the stones will be released with this maneuver. A variety of snares and baskets can be used to grasp the stones and remove them if needed. A balloon catheter also can be used to sweep the common bile duct to remove any stones. The endoscopist also can place a stent in the common bile duct, which will serve two purposes. First, any remaining stones will be softened, and potentially easier to remove with a second ERCP. Second, the stent will allow bile drainage to occur, preventing obstructive jaundice. If the stones are large, stuck, or there are many stones within the biliary tree, surgical removal is indicated. A laparoscopic or open common bile duct exploration is needed to remove any stones that can not be removed via endoscopic methods. An elective cholecystectomy is also recommended, during the same hospital admission, to prevent future episodes of choledocholithiasis. 
There are no medications that will cure choledocholithiasis. However, a one-time dose of 50 mg to 100 mg rectal indomethacin can be used to prevent post-procedure pancreatitis if the pancreatic duct was manipulated during an ERCP. Antibiotics are typically not needed for choledocholithiasis unless the patient also has an associated cholecystitis or cholangitis.
The management of common bile duct stones usually entails a team of a surgeon, gastroenterologist, radiologist and sometimes a hepatobiliary surgeon. The care of these patients is usually done by nurses. Prior to ERCP, the patient should be informed of the potential complications and recovery period. Prophylaxis against deep vein thrombosis should be employed. In addition, the patient should be taught how to use the incentive spirometer to prevent atelectasis in the postoperative period. Nausea and vomiting should be managed by the pharmacist with antiemetic medications. If the pain is severe, the patient may require prescription-strength analgesics. Finally, the patient should have a physical therapy consult and undergo a weight loss program- since gallstones are more common in obese individuals. (Level V)
Today in most experienced centers ERCP can be performed with minimal morbidity and mortality. The rate of complications reported varies from 1-5%. The biggest problem with ERCP is the technical part which can be difficult in about 5% of cases. Retained gallstones may occur in less than 1% of people and pancreatitis is known to occur in less than 3% of patients. (Level V)