What are gallstones?
Gallstones are small stones of varying size, which form in the gallbladder, a small sac that lies under the liver.
The function of the gallbladder is to store bile, a greenish-brown liquid produced by the liver. 
During the digestion of food, the gallbladder contracts and bile passes down the bile duct into the upper part of the bowel.Gallstone
Gallstones may also pass from the gallbladder into the bile duct. This involves passage through the cystic duct, a narrow tube that joins the gallbladder to the bile duct.
Why do gallstones form?
There is no simple answer to this question.
In some people, the liver produces too much cholesterol and this can result in the formation of cholesterol crystals in bile, which grow into stones.
In others, gallstones form because of changes in other components of bile or because the gallbladder fails to empty normally.
Gallstones become more common with advancing age and can be found in up to 15% of senior citizens. They are more common in women than men, with 20-30% of females developing gallstones by the age of 60.
There are other risk factors for the development of gallstones including obesity, rapid loss of weight, cirrhosis, and some disease processes involving the bottom section of the small intestine.
What symptoms do gallstones cause?
Only about three out of every ten patients who have gallstones will experience symptoms.
Both gallstones and indigestion are common and one has to be careful not to blame all indigestion-type symptoms on the presence of gallstones.

If gallstone symptoms develop, the patient is likely to experience one of the following:

Gallbladder contraction after heavy meals in a patient with gallstones can result in an intermittent, often severe, pain which is experienced in the upper, middle or right hand side of the abdomen or even in the right shoulder and sometimes under the breast bone. These colicky attacks will last for several minutes to several hours. They frequently will occur at night.
Gallbladder Inflammation:
Occasionally the stones in the gallbladder can irritate the gallbladder causing acute inflammation. In this condition, the pain is usually more long lasting and tends to be more often in the right side of the abdomen. Fever is often present and the patient is usually tender below the rib cage on the right hand side.
When a gallstone leaves the gallbladder and gets caught in the bile duct, this will block the flow of bile from the liver and cause the patient to become yellow or jaundiced. The urine will often turn dark in colour and the stool becomes lighter in colour.

How are gallstones diagnosed?

The first investigation is usually an ultrasound study. This test is relatively simple, free of side effects and is highly accurate for showing stones in the gallbladder. In this test, sound waves are beamed into the gallbladder and if there are stones present, the wave is reflected back (echoed) to the machine which picks up and documents this echo.
Another test that can be used includes a radionuclide bile duct scan where a small amount of radioactive material is injected into the vein. It is then concentrated by the gallbladder. An agent (often a fatty meal) is then given to cause the gallbladder to contract and empty.
Additional investigations may be required for people with serious complications or those who are thought to have stones in the bile duct.
For example:
  * A flexible tube (endoscope) test called endoscopic retrograde cholangiopancreatography (ERCP) may be required to demonstrate and remove bile duct stones. In this test, an endoscope is passed through the oesophagus and stomach into the bowel and x-rays are taken after dye is injected into the bile duct.  This test is invasive. 
  * Endoscopic Ultrasound (EUS). This procedure is less invasive and frequently performed initially to see if ERCP is necessary. An ultrasound probe at the tip of an endoscope is positioned in the duodenum and the bile duct is then assessed by ultrasound.

What treatment options are available?

If you do have gallstones and are experiencing colicky pain, it is best to avoid large meals and especially fatty foods and oils.
If you are overweight, then weight loss is certainly recommended. However, if you have symptoms, these dietary manipulations are rarely enough. 
Effective treatment of the gallstones usually involves one of the following choices:
1. Watchful waiting
This is the preferred treatment if the gallstones are not causing symptoms. Only in very special circumstances are gallbladders removed surgically if there are no symptoms.
2. Laparoscopic surgery
This technique is now the treatment of choice for most patients with gallstones. A tiny incision is made through the navel and a micro video tube is inserted through it. Other needle-like instruments are then inserted through the upper abdomen and the gallbladder is picked up and dissected and together with the stones, is teased out of the small incision. With this surgery, the patient is often discharged the following day.
3. General surgery
This is sometimes necessary and does involve a 6-15cm incision in the right upper abdomen and a stay in hospital of 4-6 days or more. This operation may be necessary in some patients because of technical problems with the laparoscopic surgery. 
4. Dissolving gallstones
As the gallbladder is usually functioning poorly, removal of the gallstones and leaving the gallbladder frequently results in gallstone recurrence. Drugs have been produced which can, in certain selected patients, dissolve gallstones. This approach however, is now only rarely considered.
5. Gallstone shattering
Gallstones and kidney stones can be shattered using a machine (lithotripter). This machine generates shock waves outside the body. This technique is also only suitable for certain patients and is more successful for kidney stones than for gallstones.
In general
  • Concoctions of oils, biliary lubricants and “cleansers” are sometimes used by alternative practitioners. There is no evidence in a scientifically validated trial that these treatments work. 
  • The body can function quite well without a gallbladder although diarrhoea can occasionally be troublesome and even more rarely, upper abdominal discomfort can occur after the gallbladder is removed.
  • Approximately one in twenty patients will continue to have episodes of gallstone-like pain and a lot of these patients are subsequently found to have irritable bowel syndrome.
  • The correct treatment for each patient depends upon the gallbladder symptoms, the patient’s age and the presence or absence of other medical and non medical factors. The decision as to the appropriate course of treatment should be taken by both you and your doctor together.
Acknowledgements: GESA – the Gastroenterological Society of Australia