This factsheet is about ascites

Ascites is the medical term used to describe the build-up of fluid within the abdomen. It is normal to have a small amount of fluid in the abdomen, which is continuously produced and absorbed but when there is an imbalance in this process, fluid can accumulate.


Causes of ascites

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The most common cause of ascites is people with liver cirrhosis (scarring) which makes up about 75% of cases. The main causes of liver cirrhosis include excessive alcohol intake and viral hepatitis (long term viral infection of the liver) or a number of other rare conditions causing liver damage. For about 15% of people with ascites, the underlying cause is found to be cancer. These include cancer of the stomach, bowel and ovary. It can also be caused by other cancers which have spread to the liver or into the abdomen. Other rarer causes of ascites include heart failure, inflammation of the pancreas, infection and kidney problems.


What are the usual symptoms of ascites?

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The main symptom of ascites is an increase in the size of the abdomen. Clothes may become tight and belt size may need to increase. If the volume of fluid becomes very large, it can be uncomfortable and can make the abdomen feel very ‘heavy’. Some people may try to adjust the way they stand or walk due to the increased abdominal size and this can result in a change of posture.  Weight gain caused by the additional fluid may lead to decreased mobility.

The build-up of fluid may put pressure on the bowel making the person want to eat less, become constipated or experience a burning pain in the centre of the chest (indigestion). Nausea (feeling sick) and vomiting (being sick) can also occur. There may be an increase in pressure on the lungs or sometimes build-up of fluid in the lungs, causing shortness of breath, especially when lying flat.

How is ascites diagnosed?

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The presence of ascites can be determined by an examination but is usually confirmed by performing an ultrasound scan of the abdomen. This can detect the presence of fluid as well as provide information about how much fluid there is along with other important information about the internal organs, especially the liver. Blood tests and possibly further scans may be needed to try and work out the cause of the ascites. In addition, a sample of the abdominal fluid may also be taken to find the cause. This is carried out using a small needle and usually causes only mild discomfort.

How can ascites affect you?

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Ascites can affect a person in two main ways. The first is its overall impact on general wellbeing which may include discomfort in and around the abdomen, issues with mobility and posture, nausea or vomiting and shortness of breath. There can also be embarrassment about appearance leading to a reluctance to go out in public and a curtailment of enjoyable activities. Fluid build-up should always be reported to your doctor who may recommend a change in treatment or drainage of the fluid.

The other way that ascites can affect you is because of the complications from the actual condition. These include:

  • Infection within the fluid. This can cause fever, confusion and make people feel very unwell. This is a potentially dangerous complication so if these symptoms occur it is important to see a doctor straight away.
  • Medications used to reduce the fluid can cause changes in salt and potassium levels which can be dangerous and can also affect kidney function, so it is important to have regular blood tests.


What treatments are available for ascites?

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It can be treated in various ways, from lifestyle and dietary changes to medication and medical procedures. All patients with ascites caused by liver cirrhosis are advised to minimize or stop drinking alcohol because alcohol will further increase liver damage and worsen fluid build-up and response to treatment. It is important to avoid adding excess salt to your food so you may be seen by a dietitian to discuss this and be aware that many foods contain more salt that might be expected. In some mild cases of ascites, reducing salt intake is enough to control it. However, if this fails or the volume of ascites is more significant, medications called diuretics (‘water tablets’) may be necessary. These work by removing excess fluid, partly by increasing the amount of urine the body produces.

Unfortunately medication will not prevent build-up of fluid. In this case further treatment may be necessary to remove the fluid. This is called paracentesis, also known as an ‘ascitic drain’. This involves numbing the skin on the side of abdomen, then inserting a small tube into the abdominal cavity to drain the fluid. The tube is then removed once the fluid has drained. If the fluid re-accumulates, this procedure may need to be repeated.

Some people may have ‘refractory ascites’ which means that there is no response to low-salt diet or medications, leading to the need for frequent drainage (paracentesis) whilst others may develop side effects from medications. Treatment options in this situation include a radiological (x-ray guided) procedure to reduce the pressure in the liver which drives the formation of ascites in liver disease (called a ‘transjugular intrahepatic portosystemic shunt’ or ‘TIPSS’).  In some cases refractory ascites will be one of the factors that results in the person being put forward for a liver transplant.

Does ascites need to be monitored and, if so, how?

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Yes it does need to be monitored. Regular measurements of weight and abdominal size are useful ways to monitor the volume of fluid as rapid weight changes can indicate fluid loss or gain. If you feel your weight is changing very quickly you may need to see a doctor for a check-up. Whilst taking diuretic medication, it is important to have regular blood tests to monitor salt levels and kidney function, as diuretics can affect how the kidneys work. If diuretics have only just been started, these blood tests will occur more frequently until the body is used to the medication.


How can ascites affect you over time?

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This largely depends on the underlying cause. The majority of cases of ascites caused by cirrhosis will respond to treatment. However, some cases will not respond to medication or dietary changes and may continually re-accumulate. In which case repeated drainage of the fluid may become necessary.

What to ask your doctor?

  • Do I need to avoid any foods? Do I see a dietician or is there a diet sheet?
  • Does ascites mean my condition is worsening?
  • Does the fluid need to be drained? What specific symptoms should I look for to know if drainage is needed – is measuring my weight helpful?
  • Are they any medicines I can take? Do the medicines have any side effects?
  • What support should I need at home? Can you help to provide this?


What more research needs to be done on ascites?

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Further research is necessary to find new medications that are effective at reducing ascites and clinical trials of potential candidates are ongoing. In addition, research into cirrhosis and spread of cancers will have an impact on what we know about controlling ascites.


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