Ascites: symptoms, causes and treatment of fluid in the tummy

Liver UK says the main sign of ascites is a swollen belly. Early on it can be hard to notice changes, and you might feel or see a new heavy, sagging weight around your middle, or your belly might move in an unusual wave-like motion when pushed. In the later stages the belly might be very obvious and may feel hard or tight.

Cancer Research UK says ascites can make the tummy feel tight and very uncomfortable, and often develops over a few weeks but might happen over a few days. The pressure on organs and the diaphragm may lead to the symptoms in the table. You may not have all of them.

Cancer Research UK explains that the abdomen contains many organs in a space lined with a sheet of tissue called the peritoneum, made up of two layers that produce a small amount of fluid so organs can slide around slightly. Sometimes the fluid builds up between the two layers, which makes the abdomen swell. This is ascites.

Liver UK describes it as a complication of decompensated cirrhosis and a serious symptom of liver disease. In most cases it can be controlled with medicine, but sometimes hospital treatment is needed to drain the fluid.

In cirrhosis, Liver UK explains that the liver has permanent scars from long-term damage, which makes it hard for blood to flow through the main vein of the liver and causes pressure to build up (portal hypertension). The pressure forces fluid out of blood vessels into the belly, and the liver also changes how the body handles fluid and salt. A damaged liver also tends to make less albumin, a protein that helps stop fluid leaking out of blood vessels.

Cancer Research UK lists cancers that can cause ascites, including ovarian, womb, bowel, stomach, pancreatic and liver cancer, mesothelioma of the peritoneum, and cancers that start outside the abdomen such as lung and breast cancer. It says other conditions that can cause ascites include liver disease, heart disease, pancreatitis and some infections including tuberculosis, and it can also be a side effect of some cancer drugs.

Liver UK says your doctor might suggest an ultrasound or CT scan to confirm ascites, and that if it is more advanced it can be diagnosed from symptoms and medical history. Cancer Research UK says you may have an ultrasound scan, blood tests to check your general health and how well your liver and kidneys are working, a CT scan, and a sample of fluid taken from the abdomen (paracentesis) to check for cancer cells or infection.

For paracentesis, local anaesthetic numbs the skin and a needle is put into the abdomen to take a sample of fluid. Cancer Research UK says it can be uncomfortable but is not usually painful, and ultrasound may be used to guide it.

Treatment depends on the cause. For ascites due to cirrhosis, Liver UK describes the following approaches, often used together.

Liver UK says ascites is a common problem for people with decompensated liver disease and can be very difficult, but there are things you can do. Do not drink alcohol, talk to a registered dietitian about what to eat, reduce the salt in your diet and follow the instructions on medicines, taking them regularly.

Salt is in many foods, especially processed foods, and is not always obvious, so reading labels is important. Liver UK says it is also important that you still get all the energy, protein and nutrients you need, which is why dietitian advice helps.

Liver UK says that if you have a liver condition you should contact your doctor as soon as possible for a swollen belly, leg swelling, easy bruising, changes to the belly button, loss of appetite, sudden weight gain, difficulty breathing (especially when lying down), abdominal pain, feeling or being sick, or fever and pain in your belly, which could mean an infection.

The NHS cirrhosis page says to ask for an urgent GP appointment or get help from NHS 111 if you have cirrhosis and your skin or eyes look yellow, you are more short of breath than usual or you have a swollen tummy, legs, ankles or feet. It says to call 999 or go to A&E if you are vomiting blood or your poo is very dark or black.

On the NHS, ascites is usually managed by a hospital liver or gastroenterology team, with an ascites clinic for repeated drainage, and by cancer teams when cancer is the cause. Your GP is the first contact for new swelling.

Private hepatology services can offer assessment, scans and drainage, and the same tests are used. Whichever route you use, ask who will manage repeat drainage, which diet advice you will be given and how to reach the team quickly if you develop a fever or abdominal pain.