Gallbladder stones (a disorder called cholelithiasis) sometimes pass into the bile ducts, or stones can also form directly inside the bile ducts. The bile duct stones are called choledocholithiasis. These stones sometimes obstruct a bile duct.
Usually, gallstones do not produce symptoms, but if symptoms or other problems occur, treatment is necessary. In the United States, more than half a million people undergo surgery every year to remove the gallbladder.
In the western world, the main component of most gallstones is cholesterol, a fat (lipid) that normally dissolves in bile (but not in water). When the liver secretes an excess of cholesterol, the bile becomes supersaturated with this excess and creates solid particles (cholesterol crystals). These microscopic crystals are stored in the gallbladder, where they agglomerate and become gallstones.
Gallstones can stay in the gallbladder or pass into the bile ducts. Stones can clog the cystic duct, the bile duct or the Vater blister (where the bile duct joins the pancreatic duct). Most cholesterol calculations in the bile ducts come from the gallbladder.
Any narrowing (stenosis) of the bile ducts can block the flow of bile or reduce its velocity, and in this case bacterial infections can occur.
Sometimes microscopic particles of cholesterol, calcium salts, bilirubin and other materials accumulate, but do not form stones. This material is called bile mud. Bile mud develops when bile remains in the gallbladder too long, as it happens during pregnancy. Bile mud usually disappears when the cause is resolved, for example, at the end of pregnancy. However, bile mud can form gallstones or enter the bile ducts and block the ducts.
Síntoms
About 80% of people with gallstones have no symptoms for many years, and sometimes never, especially when the stones remain inside the gallbladder.
Gallstones can cause pain. This develops when the stones pass from the gallbladder into the cystic duct, the bile duct or Vater's blister, and block the duct. Then the gallbladder becomes inflamed and causes the characteristic pain called biliary colic. The pain is located in the upper abdominal region, most often on the right side, below the ribs. It is sometimes difficult to pinpoint the location, especially in people with diabetes and those of older age. The pain, characteristically, increases in intensity over 15 minutes to 1 hour and remains stable for up to 12 hours. Often, the pain is intense enough to take the patient to the emergency department for relief. Once the pain begins to subside, which can take between 30 and 90 minutes, it becomes a dull ache. Frequently, patients feel nauseous and vomit.
If the obstruction persists, the gallbladder begins to swell (a disease called acute cholecystitis). When the gallbladder is inflamed, bacteria proliferate and an infection can occur. Usually, inflammation causes fever.
Obstruction of the bile duct or Vater's blister is more severe than obstruction of the cystic duct. Choledochal obstruction can cause a widening of the pathways (dilation). It can also cause fever, chills and jaundice (yellowing of the skin and whites of the eyes). This combination of symptoms indicates that a serious infection called acute cholangitis has appeared. Bacteria can migrate to the bloodstream and cause serious infections in the rest of the body (septicemia). Foci of pus (abscesses) can also be produced in the liver.
Treatment
- Surgery to remove the gallbladder (cholecystectomy)
- Sometimes medications to dissolve gallstones
- Occasionally, removal of gallstones by endoscopic retrograde cholangiopancreatography (ERCP)
Lithotripsy
In more than 90% of cases, choledocolithiasis or the presence of stones in the bile ducts can be solved by avoiding surgery, using the technique of retrograde endoscopic cholangiography (ERCP) by conventional methods. Sometimes, however, the large size of the stones in the bile ducts, their location in the intrahepatic bile ducts, or their impact on the bile ducts do not make it possible to use this technique.
Lithotripsy is a gallstone fragmentation technique that has proven safe and effective in more than 90% of cases. The laser lithotripsy technique for choledocholithiasis is recommended in the North American and European clinical guidelines for the management of this condition. The main advantage it offers is that it allows precise addressing under direct vision, thereby reducing the risk of injury to the patient's bile duct and the easy fragmentation of large stones that can then be easily removed under conventional ERCP techniques.