Gallstones are crystal-like deposits that form in the gallbladder - a small organ under the liver that stores bile (a fluid used by the digestive system).
The stones may stay in the gallbladder and cause no symptoms, or they may irritate the gallbladder wall or block gallbladder ducts, resulting in infection, inflammation and upper abdominal pain. It is possible for the infection to spread to the liver or pancreas. Treatment can range from pain relief to surgery.
In New Zealand, the proportion of the population with gallstones may be as high as 20%.
The gallbladder is part of the digestive system. It is a pear-shaped, sac-like structure approximately 8 cm long and 2.5 cm wide, located alongside the stomach and attached to the lower surface of the liver. The function of the gallbladder is to concentrate, store, and excrete bile ( a fluid that helps in the digestion of fat).
Bile has several components including cholesterol, bile salts, and bile pigments (eg: bilirubin). It is these chemicals that can crystallise and form stones. The two main types of gallstones are:Cholesterol gallstones
The amount of cholesterol that can dissolve in bile depends on how much bile salt it contains. Too much cholesterol, or too little bile salt, tends to cause gallstones to form in the gallbladder. Approximately 80% of all gallstones are cholesterol stones.
These are formed by calcium and bilirubin and account for approximately 20% of all gallstones. Pigment stones tend to form in patients with certain blood or liver disorders.
The risk of developing gallstones tends to increase with age. Gender is also a factor, as women develop gallstones more commonly than men and at a younger age. And heredity appears to play a part in the development of gallstones as there is frequently a family history of the disease.
Other factors that increase the risk of developing gallstones include:
- Being overweight – particularly when the extra weight is carried around the waist
- Eating a high-fat, low-fibre diet
- Having diabetes
- Having high blood cholesterol levels
- Heavy drinking
As pregnancy and contraceptive pills can slow down gallbladder activity, women who have had multiple pregnancies or long-term contraceptive pill use are at higher risk of developing gallstones.
Signs and symptoms
Gallstones vary greatly in size. Some people may form one large stone, whereas others may have hundreds of tiny stones. Most commonly, gallstones are 5–10 mm in diameter.
Most people with gallstones do not experience any symptoms. If symptoms are present, the most common early sign of gallstones is upper abdominal pain. This pain usually occurs in the upper right side of the abdomen, is often severe, and may radiate to the chest, back, or the area between the shoulders. Other symptoms that may occur include:
- Nausea or vomiting
- Jaundice (the yellow appearance of skin and the whites of eyes caused by bilirubin build-up in the blood) when gallstones block the passage of bile
- Light-coloured stools.
Symptoms can occur suddenly and may be referred to as biliary colic. This type of pain is commonly set off by eating fatty foods and often occurs in the middle of the night. The symptoms experienced may be so severe that people need to seek immediate medical attention.
When infection of the gallbladder is present it is possible to also experience low-grade fever, sweats, and chills.
If gallstones are suspected, it is important to consult a doctor for an accurate diagnosis and treatment. Initially the doctor will take a medical history and perform a physical examination.
The doctor will look for signs of jaundice and will assess the abdomen for swelling and pain. Blood tests are usually performed to check the function of the liver and pancreas and to rule out other conditions that may be causing the symptoms.
The most common test used to definitively diagnose gallstones is an abdominal ultrasound scan to create pictures of the gallbladder, which are then analysed to look for signs of gallstones.
If it is suspected that gallstones are blocking the ducts, then a test called endoscopic retrograde cholangiopancreatography (ERCP) may be performed. This test involves inserting a long, flexible tube (an endoscope) down the oesophagus, through the stomach and into the duodenum. The endoscope has a light and a camera at its tip allowing the doctor to view the inside of the bowel. A special dye is injected through the endoscope into the bile duct allowing the outline of the ducts to be highlighted. Gallstones located in the ducts can sometimes be removed during the ERCP procedure.
Other specialised scans or x-rays are sometimes used to confirm the diagnosis and highlight the location of the gallstones.
In general, treatment will depend on the frequency and severity of the symptoms experienced. Approximately 30% of all people who experience biliary colic will not experience a further episode. Because of this, the doctor may advise a wait and see approach.
If attacks are occasional and mild, they may be able to be managed with pain-relieving medications, applying heat to the affected area, resting and taking sips of water. Reducing the amount of fat in the diet and maintaining a healthy body weight may also be beneficial. If attacks are frequent or severe surgery is usually recommended.
Cholecystectomy is the surgical removal of the gallbladder and is a common and routine procedure. It may be recommended when the symptoms of gallstones are problematic and/or cholecystitis is present. If there is infection or acute inflammation of the gallbladder, this may need to be treated with antibiotics before the gallbladder can be removed.
The Gallbladder is not essential to live or to digest food. When the gallbladder is removed, bile is still produced by the liver and excreted through the bile duct. Instead of being stored by the gallbladder until needed, it flows directly into the duodenum and is excreted from the body.
The two cholecystectomy techniques are:
This is the "traditional" but now-a-days less common surgical technique for removing the gallbladder and is performed under a general anaesthetic. A single incision is made below the rib cage. Through the incision, the surgeon can view the area and remove the gallbladder. The cystic duct is tied off or closed with surgical clips. The common bile duct is left intact.
Laparoscopic cholecystectomy is also performed under general anaesthetic but is less invasive and much more commonly used than the open cholecystectomy technique. It has a faster recovery time and a shorter hospital stay (usually just one night). In a laparoscopic cholecystectomy, three or four small incisions are made in the abdomen.
A telescope-like instrument (a laparoscope) is inserted through one incision (allowing the surgeon to view the inside of the abdominal cavity on a television monitor) and surgical instruments are inserted through the other incisions. The abdominal cavity is inflated with carbon dioxide gas to provide a clear field of vision and to give the surgeon room to operate. The gallbladder is located and the cystic duct is tied off or closed with surgical clips. The gallbladder is then removed through an incision in the belly button.
After a cholecystectomy, fluids may be given intravenously (through a drip in the hand or arm). Oral fluids and a light diet are introduced slowly and people are encouraged to get up and walk around soon after the operation. Once discharged, light activities only will be recommended. Those who have had a laparoscopic cholecystectomy can usually return to their normal daily routines within one to two weeks after surgery.
Those who have had an open cholecystectomy may take between two and four weeks to return to their normal daily routines. The recovery period differs according to each individual.
After discharge from the hospital, the digestive system may take a few days to return to normal so low fat, easily digestible food is recommended. A normal diet can be resumed after this but if certain foods cause discomfort they should be avoided.
Risks and complications
As with any surgery, there are possible risks and complications. These include:
- Anaesthetic complications
- Bleeding (haemorrhage)
- Wound infection
- Injury to or leakage from the bile duct
- Discomfort or numbness around the area of incision
It is important to discuss the risks and benefits of cholecystectomy with the surgeon before surgery. These factors vary with each individual case.
After surgery, patients should inform their doctor immediately if any of the following are experienced:
- Fever or chills
- Drainage from the incision site(s)
- Increasing pain or redness around the incision
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O’Toole, M.T. (Ed.) (2013). Choledocholithiasis. Mosby’s Dictionary of Medicine, Nursing & Health Professions (9th ed.). St Louis: Elsevier Mosby.
British Digestive Foundation (Date unknown). Understanding gallstones London: British Digestive Foundation.
Chapman, B.A., et al. Gallstone prevalence in Christchurch: risk factors and clinical significance. N Z Med J. 2000;113(1104):46-8
Haggerty, M. (2006). Gallstones. The Gale Encyclopaedia of Medicine. Third Edition. Jacqueline L. Longe. Editor. Farmington Hills. MI: Thompson Gale.
Polsdorfer, J. R. (2006). Gallstone Removal. The Gale Encyclopaedia of Medicine. Third Edition. Jacqueline L. Longe. Editor. Farmington Hills. MI: Thompson Gale.
Last Reviewed – January 2017