What are the complications of gallstones?
Biliary colic is the most common symptom of gallstones, but, fortunately, it is usually a self-limiting symptom. There are, however, more serious complications of gallstones.
Cholecystitis means inflammation of the gallbladder. Like biliary colic, it too is caused by sudden obstruction of the ducts, usually the cystic duct by a gallstone. In fact, cholecystitis may begin with an episode of biliary colic. Obstruction of the cystic duct causes the wall of the gallbladder to begin secreting fluid just as with biliary colic, but for unclear reasons, inflammation sets in. At first the inflammation is sterile, that is, there is no infection with bacteria; however, over time the bile and gallbladder become infected with bacteria that travel through the bile ducts from the intestine.
With cholecystitis, there is constant pain in the right upper abdomen. Inflammation extends through the wall of the gallbladder, and the right upper abdomen becomes particularly tender when it is pressed or even tapped. Unlike with biliary colic, however, it is painful to move around. Individuals with cholecystitis usually lie still. There is fever, and the white blood cell count is elevated, both signs of inflammation. Cholecystitis usually is treated with antibiotics, and most episodes will resolve over several days. Even without antibiotics, cholecystitis often resolves. As with biliary colic, movement of the gallstone out of the cystic duct and back into the gallbladder relieves the obstruction and allows the inflammation to resolve.
Cholangitis is a condition in which bile in the common, hepatic, and intrahepatic ducts becomes infected. Like cholecystitis, the infection spreads through the ducts from the intestine after the ducts become obstructed by a gallstone. Patients with cholangitis are very sick with high fever and elevated white blood cell counts. Cholangitis may result in an abscess within the liver or sepsis. (See discussion of sepsis that follows.)
Gangrene of the gallbladder is a condition in which the inflammation of cholecystitis cuts off the supply of blood to the gallbladder. Without blood, the tissues forming the wall of the gallbladder die, and this makes the wall very weak. The weakness combined with infection often leads to rupture of the gallbladder. The infection then may spread throughout the abdomen, though often the rupture is confined to a small area around the gallbladder (a confined perforation).
Jaundice is a condition in which bilirubin accumulates in the body. Bilirubin is brownish-black in color but is yellow when it is not too concentrated. A build-up of bilirubin in the body turns the skin and whites of the eye (sclera) yellow. Jaundice occurs when there is prolonged obstruction of the bile ducts. The obstruction may be due to gallstones, but it also may be due to many other causes, for example, tumors ofthe bile ducts or surrounding tissues. (Other causes of jaundice are a rapid destruction of red blood cells that overwhelms the ability of the liver to remove bilirubin from the blood or a damaged liver that cannot remove bilirubin from the blood normally.) Jaundice, by itself, generally does not cause problems.
Pancreatitis means inflammation of the pancreas. The two most common causes of pancreatitis are alcoholism and gallstones. The pancreas surrounds the common bile duct as it enters the intestine. The pancreatic duct that drains the digestive juices from the pancreas joins the common bile duct just before it empties into the intestine. If a gallstone obstructs the common bile duct just after the pancreatic duct joins it, the flow of pancreatic juice from the pancreas is blocked. This results in inflammation within the pancreas. Pancreatitis due to gallstones usually is mild, but it may cause serious illness and even death. Fortunately, severe pancreatitis due to gallstones is rare.
Sepsis is a condition in which bacteria from any source within the body, including the gallbladder or bile ducts, enter into the blood stream and spread throughout the body. Although the bacteria usually remain within the blood, they also may spread to distant tissues and lead to the formation of abscesses (localized areas of infection with formation of pus). Sepsis is a feared complication of any infection. The signs of sepsis include high fever, high white blood cell count, and, less frequently, rigors (shaking chills) or a drop in blood pressure.
A fistula is an abnormal tract through which fluid can flow between two hollow organs or between an abscess and a hollow organ or skin. Gallstones cause fistulas when the hard gallstone erodes through the soft wall of the gallbladder or bile ducts. Most commonly, the gallstone erodes into the small intestine, stomach, or common bile duct. This can leave a tract that allows bile to flow from the gallbladder to the small intestine, stomach, or the common bile duct. If the fistula enters the distal part of the small intestine, the concentrated bile can lead to problems such as diarrhea. Rarely, the gallstone erodes into the abdominal cavity. The bile then leaks from the gallbladder or bile duct throughout the abdominal cavity and causes inflammation of the lining of the abdomen (peritoneum), a condition called bile peritonitis.
Ileus is a condition in which there is an obstruction to the flow of food, gas, and liquid within the intestine. It may be due to a mechanical obstruction, for example, a tumor within the intestine, or a functional obstruction, for example, inflammation of the intestine or surrounding tissues that prevents the muscles of the intestine from working normally and propelling its contents. If a large gallstone erodes through the wall of the gallbladder and into the stomach or small intestine, it will be propelled through the small intestine. The narrowest part of the small intestine is the ileo-cecal valve, which is located at the site where the small intestine joins the colon. If the gallstone is too large to pass through the valve, it can obstruct the small intestine and cause an ileus.
Cancer of the gallbladder almost always is associated with gallstones, but it is not clear which comes first, that is, whether the gallstones precede the cancer and, therefore, could potentially be the cause of the cancer or the gallstones form because cancer is present. Cancer of the gallbladder arises in less than 1% of individuals with gallstones. Therefore, concern about future development of cancer is by itself not a good reason for removing the gallbladder when gallstones are present.