What are gallstones?

Gallstones are small, pebble-like stones that form in your gallbladder. This fig-sized organ is part of your digestive system and lies underneath your liver. Its function is to store and release bile, which aids in the digestion of fat.

Gallstones are very common. You can have gallstones for years without being aware of them. However, if a gallstone gets stuck in the opening of the gallbladder, or travels beyond the gallbladder, it can lead to a variety of different conditions.

Causes

The exact cause of gallstones is unknown, but they may be due to an imbalance in bile creation and storage. Bile is a thick, greenish-yellow coloured digestive fluid made in your liver and stored in your gallbladder. It helps your body to break down cholesterol and some fats and fat-soluble vitamins, so they can be absorbed by your body. It also helps your body get rid of excess cholesterol, bilirubin and drug by-products. When you eat these substances, your gallbladder contracts and bile is secreted into your small intestine via your biliary ducts.

Gallstones may be due to the following:

  • Your liver producing more cholesterol than you can break-down and forming crystals in your gallbladder;
  • Health conditions that cause your liver to produce too much bilirubin, a chemical produced when you break-down red blood cells, or;
  • Your gallbladder not emptying properly causing bile to become concentrated and form crystals.

Risk factors

Risk factors for gallstones include:

  • Gender – females have a much higher risk of developing gallstones;
  • Obesity;
  • Losing weight rapidly or frequent fasting;
  • Pregnancy;
  • Age – especially once you are over 40 years of age;
  • Genes – gallstones are more common in some families;
  • A lack of physical exercise;
  • Cirrhosis of the liver, and;
  • Diabetes.

Types

There are three distinct types of gallstones: cholesterol, pigmented and mixed. Knowing what they are made of is important, as it determines how well they will respond to treatment.

Cholesterol gallstones

They are usually yellowish-green in colour and are made from solidified cholesterol. They may form when your gallbladder does not empty properly, or your bile contains too much bilirubin, cholesterol, or too little bile salts.

Pigmented gallstones

These are small, dark-looking stones made from bilirubin pigments and are usually small and numerous. Their cause is unknown, but may be due to over-production of bilirubin, liver disease or other underlying health conditions.

Mixed stones

These are the most common type of gallstone and usually grow in batches. They are made from salts and cholesterol.

Signs and symptoms

The symptoms you experience will depend on the size, type and location of your gallstones. Roughly 70% will lie dormant without bothering you at all1 – ‘silent gallstones’ – and only be discovered during investigations for other conditions.

Gallbladder with gallstones, gallstones.

Gallstones in the gallbladder.

Gallstones can cause sudden, severe pain in the upper abdomen, which is known as biliary colic. A gallstone can become stuck in the opening of your gallbladder or in the ducts that carry bile from your liver to the gallbladder and to the intestine. The ducts and gallbladder try to contract their muscular walls against the blockage which results in increased pressure and pain. The pain can start suddenly – often within half an hour of eating fatty foods and can last for anywhere between a few minutes and several hours. It may start underneath your ribs, on your right-hand side or between your breastbone and belly button. Sometimes the pain will spread to your right shoulder blade, your back and your side. It may make it difficult to take a deep breath and might also wake you at night.

Biliary pain, pain after eating fatty foods, pain under ribs.

Gallstones can cause sudden and extreme pain, known as biliary colic.

Other symptoms can include:

  • Nausea, vomiting, fever and diarrhoea;
  • Dark-coloured urine and pale stools, and;
  • Jaundice – yellowing of the skin and whites of your eyes. 

Methods for diagnosis

Your doctor will take a full medical history to rule out other serious conditions with similar symptoms and ask if you have any close relatives with gallbladder issues. You may also be examined to idenitfy the underlying cause for the pain. A common bedside test is to breathe in while your doctor taps on the area above your gallbladder. If there is extreme pain, it may help confirm a diagnosis of an inflamed gall bladder (cholecystitis), often caused by gallstones. This is called Murphy’s sign.

Your doctor may perform blood tests including a full blood count, liver function test and pancreatic function test. The following tests can also be performed:

  • An ultrasound – this uses a device that emits high-frequency sound waves to produce images of your body’s internal structures. This is the most commonly used test and usually sufficient for a diagnosis of gallstones and conditions such as cholecystitis;
  • Magnetic resonance imaging (MRI) – which uses magnetism and radio waves to create an image of the body composed of multiple cross-sections; this can provide more detailed images than ultrasound of the bile ducts and is a safe non-invasive test. It can however be expensive and not readily available;
  • Endoscopic ultrasound – a tube with an ultrasound transducer on the end is fed into your small intestine via you mouth and the ultrasound is performed internally. This is superior to external ultrasound as the device can be placed very close to the bile ducts and there is no interference from abdominal fat and bowel gas. It is an invasive procedure but does not require any toxic dyes to be used;
  • A computerised tomography (CT) scan – which uses X-rays to develop a 3D image of the body. This test is not necessarily more effective in the diagnosis of gallstones. It may be helpful in diagnosing other conditions that can mimic symptoms of gallstones;
  • Cholescintigraphy or hepatobiliary iminodiacetic acid (HIDA) scan – this uses a radioactive marker administered intravenously, prior to capturing images with a nuclear medicine scanner. It assesses the elimination of the radioactive marker by the gallbladder, and can more accurately diagnoes an underlying gallbladder problem, or;
  • Cholangiography – this involves introducing a radiopaque dye into your bile ducts, prior to an X-ray, to verify if you have any stones present. If a stone is detected it can be removed at this stage using ERCP (see Types of treatment below).

Types of treatment

Gallstones that are found incidentally and do not cause symptoms, generally do not need treatment. Where it does cause symptoms, the following treatments may be recommended: 

Immediate treatment

During an acute attack of biliary colic, treatment focuses on managing the pain with pain-relief medications. It is important to be assessed by your doctor to accurately diagnose this condition, and exclude other serious causes. The pain typically settles within a few hours. However, it is generally advisable to maintain a low-fat diet in the days immediately following an attack, which can also be extended to long-term.

Further treatment 

Once an individual develops symptoms and/or complications from gallstones, surgical treatment is generally recommended. 

Gallbladder removal surgery

Surgery to remove your gallbladder, known as a cholecystectomy, is a relatively straightforward procedure. Your surgeon may use either laparoscopic (keyhole) or open surgery to remove your gallbladder. Both operations are performed under general anaesthesia.

Laparoscopic (keyhole) cholecystectomy

This is the most common, and least invasive, type of surgical removal of the gallbladder. It uses small incisions in the abdomen, to allow slender surgical instruments and a camera, to carefully remove the gallbladder under vision. The gallbladder is often removed through one of the small incisions and sent to the laboratory for further examination. Recovery from laparoscopic cholecystectomy is usually rapid, requiring on average one night in hospital, and then two weeks prior to return to normal activites. 

Open cholecystectomy

In some circumstances, your surgeon may prefer to do open surgery. This involves making a 10-15cm cut in your abdomen to reach your gallbladder and remove it. This is a more extensive procedure, which is generally performed for more difficult cases. You will probably stay in hospital for 3-5 days and return to normal activities after six weeks.

Cholecystectomy risks

With either procedure, the specific risks are injury to the delicate bile ducts, liver, bowel and other intra-abdmonial structures. To help reduce the risk of inadvertant injury to the bile ducts, an intra-operative cholangiogram is usually performed. This is where radiopaque dye is injected through the ducts, at the time of operation, and an X-ray performed. This study helps identify any bile duct injuries, abnormal anatomy and any gallstones that may have migrated through the ducts.

Other treatments

Occasionally, medical treatment can be used either alone or in combination with surgical treatments. These are more effective for small gallstones of less than one centimetre in size, and in individuals with an otherwise normal gallbladder. These treatments include:

Medications

If you have gallstones that are small and do not contain calcium, you may be offered ursodeoxycholic acid to dissolve them. This treatment takes up to two years to work though and is not considered very effective, as your stones tend to return once you stop taking it.

Lithotripsy

Lithotripsy uses sound waves to break up small, soft stones and is only used on a minority of people.

Endoscopic retrograde cholangiopancreatography

Endoscopic retrograde cholangiopancreatography (ERCP) is used to remove gallstones from your bile duct by artificially widening it, or making an incision. Sometimes a small tube, called a stent, may be left in place to keep your bile duct open. If you have stones inside your gallbladder, they will be left in place.

A flexible tube called an endoscope is fed into the first part of your small intestine via your mouth and a temporary, radiopaque dye is squirted into your biliary ducts. You will then have an X-ray to examine your biliary ducts and check for stones. Using an attachment on the endoscope, your surgeon can try to remove any stones blocking your ducts, or let them pass into your small intestine.

Potential complications

Gallstones can lead to a number of different complications, which include:

Acute cholecystitis

Acute cholecystitis is the acute inflammation and/or infection of the gallbladder. This can occur when a stone completely blocks the opening to your gallbladder or if the ducts draining the gallbladder become blocked. Sometimes cholecystitis can occur without any stones, due to the build up of thick bile. Cholecystitis presents similar to biliary colic, except the pain can be longer lasting. Additional tests can help differentiate between the two conditions. Cholecystitis can lead to severe gallbladder infection, sepsis (infection spreading into the blood), jaundice, and/or an abscess. Prompt treatment with pain-relief medications, antibiotics, and timely surgery are recommended. 

Acute cholangitis

This is inflammation of your bile ducts, which can be caused by stones and/or infection. You may develop a fever, jaundice, chills, confusion, itchy skin and abdominal pains. This is a serious medical condition that warrants treatment with intravenous antibiotics and removal of the offending gallstone(s), if present. 

Acute pancreatitis

If a gallstone moves and blocks the duct leading to your pancreas (part of your digestive system), this can cause inflammation. You may feel a sudden, dull but severe pain in the upper centre of your stomach. The pain may move along your back and get worse after you have eaten. You may develop diarrhoea, sickness, vomiting and a high temperature. Hospitalisation is usually required, with good recovery rates. Treatment may include pain-relief medications, antibiotics, simple diet and removal of the offending gallstones, if present.

Jaundice

When the ducts from the liver are blocked, bile cannot reach the intestine or gallbladder and it is ‘backed up’ in the liver. This in turn results in an increase in the bilirubin substance in the blood stream. High levels of bilirubin in the blood turn your skin and whites of your eyes yellow (jaundice), and your urine dark in colour, as the kidneys have to excrete the excess bilirubin. Your stools may be pale and have a high fat content. Your skin may also be itchy as the bile is an irritant.

There are numerous causes for jaundice, however, gallstones causing an obstruction within the bile ducts is a potential cause.

Cancer of the gallbladder

Cancer of the gallbladder is incredibly rare, but a potentially serious complication. High levels of calcium in the wall of your gallbladder and a family history of gallbladder cancer are risk factors. It may be considered safer to remove your gallbladder as a precaution if you have these risk factors. Symptoms are high fever, jaundice and pain in the abdomen but there may also be no symptoms in early stages.

Gallstone ileus

Gallstone ileus occurs when a stone travels through a fistula, an abnormal tunnel between the gallbladder and the bowel, and causes a blockage of the small bowel. This occurs mainly in elderly people. Symptoms may include abdominal bloating with pain, nausea, vomiting and constipation. Gallstone ileus requires immediate medical attention, as your bowel may perforate.

Prognosis

In the majority of cases, gallstones are symptom-free and you will not need any treatment. Eating a healthy diet, maintaining a healthy weight and exercising regularly may help keep you symptom-free and reduce your risk of developing gallstones. If you do decide to lose weight, do it gradually, as yo-yo dieting and skipping meals can lead to further gallstone formation.

Prevention

Eating a healthy diet that includes lots of fruit and vegetables and less fatty foods is the best way to prevent gallstones. Getting regular exercise to maintain a healthy weight is also recommended. Visit your doctor to discuss your cholesterol levels and get a referral to your local dietician if you are concerned about developing gallstones. 

Last Reviewed: 03/10/2018

Reproduced with permission from Health&.