Gallstones are solid formations made from protein, calcium, bile salts, bilirubin and cholesterol (waste products) that develop in the gallbladder. In general, gallstone disease is also called cholelithiasis. If the condition stones are located in the bile ducts, the condition is called choledocholithiasis. There are two types of gallstone: pigment and cholesterol stones. Pigment stones are caused by excess bilirubin in the bile, while formation of cholesterol gallstone is due to excess cholesterol in the bile. The size and number of gallstones vary. Gallstones usually start during puberty, a period when the concentration of cholesterol in the bile increases.
Gallstone disease is a common condition that affects approximately 25% of women and 10-15% of men over the age of 50. The incidence of gallstones is particularly high in American Indians and Mexican-Americans and low in Blacks. They are more prevalent in older individuals than in young.
Several genetic, medical, lifestyle and environmental factors contribute to the development of gallstones. Genetic factors are apparently important based on the observation of racial and familial tendencies. Obesity and food high in fat and cholesterol may cause gallstones as a result of impaired fat metabolism or increased cholesterol. People with diabetes are also at higher risk of developing gallstones. Gallstones may be caused by other conditions such as Crohn's disease, liver disease and hemolytic blood disorder.
Sudden changes in diet may also contribute to development of gallstones. For example, cholesterol increases when there is rapid weight loss, because the liver excretes extra cholesterol into the bile. High levels of estrogen in women (pregnant or taking hormonal replacement therapy) increases the risk of developing gallstones. Cholesterol-lowering drugs, which lower the cholesterol levels in the blood, can increase the secretion of cholesterol in bile and therefore increase the risk of gallstones.
Most gallstones cause no symptoms, however, when they migrate or lodge in the bile duct, the patient can develop several symptoms such as:
- Abdominal pain (pain may radiate to the right upper back or shoulder blade area)
- Nausea and vomiting
- Inability to tolerate fatty food
In diagnosing gallstones, the doctor will start by asking questions relative to the patient's medical history and symptoms. Normally, this will be followed by a physical exam to assess any pain or tenderness in the abdomen.
There are several tests that can be used to confirm the presence of gallstones and complications arising from it:
- Complete blood count in order to check for infection and other complications detectable by blood tests.
- Magnetic resonance cholangiogram (MRC) is a test used prior to surgery to locate gallstones. It also enables inspection of potential abnormalities in the gallbladder or bile ducts. It uses a magnetic field and pulses of radio wave energy to capture images of structure inside the abdomen and organs.
- Hepatobiliary (HIDA) scan is performed after a special radioactive dye is injected into a vein in the arm. The dye will reveal the structure of the gallbladder and will show if the gallbladder is functioning well.
- Computed tomography (CT) scan to visualize anatomical structures in the abdomen, including the gallbladder.
- Abdominal ultrasound uses ultrasound technology to scan the gallbladder and adjacent area. It is widely available and has good sensitivity in detection of gallstones, contributing to effective management of patients with gallstones in the general practitioner setting.
- Abdominal X-ray is a widely available visualization method, but can only detect some gallstones.
- Endoscopic ultrasound (EUS) uses an endoscope with an ultrasound probe and inserts it from the mouth to the stomach to assess the tubes that drain the liver, gallbladder and pancreas. It is an effective and safe method of diagnosis.
- Endoscopic retrograde cholangio-pancreatography (ERCP) uses an endoscope and inserts it from the mouth to the stomach to assess the tubes that drain the liver, gallbladder and pancreas. Also, this allows the doctor to remove stones that causes blockage in the bile duct using a special instrument that is inserted in the endoscope.
Patients with gallstones that do not display any symptoms normally are not referred to treatment. Treatment of symptomatic gallstones depends on the stage of the disease.
The available treatment options include:
- Medical dissolution uses drugs such as ursodeoxycholic acid to dissolve the gallstones. This is normally the approach used for patients at high risk of complications from surgery. It also can be performed in combination with other treatments (either after or before).
- Surgery, consisting on the resection of the gallbladder (cholecystectomy) is the most effective treatment approach for gallstones. After cholecystectomy, the bile will flow directly from the liver into the small intestine, rather than being stored in the gallbladder. There are two methods for performing cholecystectomy:
- Laparoscopic cholecystectomy uses a minimally invasive approach which results in reduction of postoperative pain and disability. It is safe and effective and is seen as the treatment of choice by many.
- Open cholecystectomy surgery is the traditional surgical approach, which is widely used, safe and effective.
- Endoscopic retrograde cholangio-pancreatography (ERCP) may be used in combination with laparoscopic interventions (either after or before) to accurately localize the gallstones, increasing the efficiency of the treatment and reducing the risks of complications. If after ERCP is concluded and the laparoscopic approach is not possible, open intervention could then be performed. Its use as a primary treatment choice depends not only on the exact presentation of the patient, but also on the level of expertise of the ERCP technicians, which may vary across institutions.
- Endoscopic retrograde sphincterotomy (ERS): similarly to ERCP, enables the perioperative management of gallstone patients, particularly when combined with laparoscopic approaches.
Fruit juices and herbal remedies are popular treatments for gallstones. Lemon juice, for example, is thought to help in detoxification of the organism and is many times recommended as a complementary treatment. Alternative diet approaches for gallstones are broadly safe, but should be used with caution as certain herbs can interact with conventional treatments for gallstones.
The prognosis of gallstone is good since there are effective treatments available. Gallstones can develop without causing symptoms, and there is a little possibility of gallstone complications if it is treated immediately.
People with gallstone can lower their risk of complications by exercising regularly, eating a healthy balanced diet and maintaining a healthy weight. Avoid fatty and high-cholesterol foods, which can aggravate the condition and precipitate the onset of symptoms.
Genetic studies are pinpointing factors associated with development of gallstones, such as the hepatic cholesterol transporter ABCG8. This genetic information is now being used to develop new treatment strategies. The link between diabetes, insulin resistance and gallstones is also being investigated.