Gallstones

Background information

About 15% of people in New Zealand will develop gallstones over a lifetime.

They are more common in;
- Women.
- People who are overweight.
- Family history of gallstones.

There are several different types of gallstones.
- Most stones are formed from a supersaturated solution of cholesterol in the gallbladder.
- Only 10% of gallstones will show on a plain X-ray.
- Most gallstones are picked up on abdominal ultrasound.

Most stones start as a small cholesterol crystal.
- The crystal slowly grows depending on the saturation of bile salts and cholesterol in the bile.
- The function of the gallbladder may be important. Failure to empty normally could an important factor.
Pigment stones (10% of all gallstones).
- These occur because of increased breakdown of blood.

Biliary colic – gallstone pain.

Stones in the gallbladder may cause abdominal pain - this is called biliary colic.
- This pain is usually an “attack” with sudden onset and lasts for 4-6hours.
- The pain is mainly in the right upper abdomen but can also be in the lower chest and back (over the right shoulder blade).
- There is often nausea and/or vomiting. You may appear to be pale and have excess sweating
- The severity of the pain is often enough to want to seek out urgent medical attention.
- Sometimes the pain is confused for a heart attack.
- There can be repeated episodes of pain but not usually daily episodes.

Biliary colic is caused by a stone lodging in the outlet of the gallbladder.
- Most of the time the stone falls back into the gallbladder and the “attack” is over.
- Biliary colic may be brought on by a large fatty meal because this causes strong contractions of gallbladder.

If the pain lasts for more than 6 hours then a complication may have arisen.
- The main potential complication is inflammation of the gallbladder. This is called acute cholecystitis. Hospital admission is essential.
- Another complication is migration of a stone to the main bile duct. This leads to jaundice; often infection (cholangitis) or pancreatitis.

Treatment involves
- Intravenous fluids, pain relief, antibiotics.
- Then proceeding to cholecystectomy (removal of the gallbladder) – usually during the same hospital admission.
- Sometimes there is a preference for waiting for the inflammation to settle down before proceeding to surgery.

Gallstones on ultrasound but no pain.

This is a common situation. Ultrasound of the abdomen is a common investigation that is done for a wide variety of reasons.
Many gallstones that are picked up on ultrasound will be causing no symptoms.
- 60 - 80% of all gallstones cause no problems.
- About 20% of people with gallstones picked up by chance will develop symptoms due to the gallstones over the next 20 years.
- Therefore most people would think that watching and waiting is the best response rather than an operation.

Symptoms of indigestion, fullness or bloating after meals, nausea or heartburn are not due to gallstones.

Gallstone type of pain but no gallstones

This is also a common situation. Pain in the right upper abdomen may be similar to gallstone pain (biliary colic) but no stones are found when the ultrasound is done.

The most likely explanation is that the pain does not arise from the gallbladder but from the colon or from the stomach.
- Pain from the colon is due to irritable bowel syndrome. Pain with IBS can occur anywhere in the abdomen.
- Sometimes constipation leads to distension of the colon on the right side of the abdomen and right-sided abdominal pain.
- A gastroscopy should be performed to check for peptic ulcer or acid reflux.
- A trial of medical therapy and/or dietary manipulation focused on IBS as a possible diagnosis may be considered first. Patients with IBS are 7 times more likely to have had a cholecystectomy - this strongly suggests that cholecystectomy has been inappropriate for many of these patients.

There is a debate as to whether the gallbladder can give rise to pain in the absence of gallstones.
- There is some suggestion that a “non-functioning gallbladder” is associated with episodes of pain.
- This means that the gallbladder does not take up the bile coming down from the liver.
- This “non-functioning” state can be detected by a radionuclear scan called a HIDA scan.
- A scan showing a “non-functioning” gallbladder predicts a reasonable success rate with cholecystectomy (perhaps 2/3 will have symptom relief).

Gallstones

Gallstone pain and gallstones found.

This is the easiest situation. There is only one way ahead and that is to have a cholecystectomy - surgery.
There are no sensible alternatives to this operation.
- Dissolving gallstones was tried and found not to be a successful approach.
- Taking out the stones without taking the gallbladder led to a high rate of recurrent stones (forming again in the gallbladder).
- Crushing/ shattering gallstones with a lithotripter machine, in a manner similar to kidney stones, is technically possible but is not successful in the long term.

Cholecystectomy is now routinely performed by a laparoscopic approach (keyhole surgery).
- The average hospital stay is 2 days.
- Not everybody can be done by this approach – advice from your surgeon is required.
- Previous surgery in the upper abdomen may make a keyhole approach more difficult

Surprisingly, digestion of food is unaffected by taking out the gallbladder.
- The function of the gallbladder is to concentrate bile made by the liver and to deliver the concentrated bile to the small bowel at the time of a meal.
- Without a gallbladder smaller amounts are delivered to the small bowel (at times unrelated to meals.
- There is enough reserve function in the digestive process so this problem with bile flow doesn’t seem to matter.

However about 1% of people develop diarrhoea after a cholecystectomy.
- This may be due to an irritant effect of bile salts on the colon.
- It is effectively treated with cholestyramine (specialist review is required).

There is an association of cholecystectomy with irritable bowel syndrome.
- It is most likely that this is because the pain of IBS was mistaken for biliary colic (gallstone pain).

Xray of a stone in the main bile duct - retrieval with a basket (ERCP)

Further attacks of gallstone type pain after removal of the gallbladder

This may be due to a stone left behind in the main bile duct.
- The chance of a retained stone after cholecystectomy is about 4%.
- The treatment will depend on the situation.
- The most common approach is an ERCP (Endoscopic retrograde cholangiography).
  - This is like a gastroscopy but with specialized equipment to retrieve stones from the bile ducts.
  - It is an outpatient procedure performed with sedation.

Most often further tests do not show any stones left behind in the bile ducts.
- The explanation may be that the initial symptoms were not due to the gallstones.
- Possible diagnoses include irritable bowel syndrome or a “sensitive stomach” or constipation.
- This needs careful evaluation by a surgeon or gastroenterologist

It is not possible to prove with absolute confidence whether the symptoms did relate to the gallstones.
- The decision to proceed to a cholecystectomy is always a judgement call.
- Therefore sometimes a cholecystectomy is performed for what are essentially asymptomatic gallstones.

A small proportion of people with continuing attacks of biliary colic have an abnormality of the valve at the bottom of the bile duct (where the bile duct enters the duodenum/small bowel).
- This is called Sphincter of Oddi dysfunction.
- It is a genuine problem but it is a diagnosis that is difficult to prove or exclude and there is often doubt as to whether this abnormality is actually causing the pain.
- There has been interest in cutting the muscle fibres of this sphincter at the time of an ERCP (called a sphincterotomy). A recent large study has shown no benefit and this is now rarely performed
- This procedure had some risks – particularly causing pancreatitis.
- Most treatment is now directly at pain management such as low dose amitriptyline or gabapentin - also some treatments for IBS may help