Ascites (Fluid in the Abdomen)

How ascites forms

In cirrhosis, scarring raises pressure in the portal vein that drains the gut to the liver (portal hypertension). Blood vessels in the gut widen, the body senses low effective blood volume, and the kidneys retain salt and water. Meanwhile, high pressure pushes fluid out of the liver and gut vessels into the abdomen. Low blood albumin, from reduced liver production, makes it worse.

Other causes work differently: in cancer, tumor deposits on the abdominal lining leak fluid; in heart failure, back pressure through the liver causes leakage; in nephrotic syndrome, protein loss lowers albumin.

Causes

Symptoms

Small amounts of fluid cause no symptoms. As fluid builds up:

• the belly swells and feels tight; clothes and belts become too small
• rapid weight gain despite muscle loss elsewhere
• the navel may flatten or bulge outward, and hernias appear
• early fullness when eating, nausea, reflux
• shortness of breath as the fluid pushes on the diaphragm, sometimes with fluid around the lungs
• swollen ankles and legs

Diagnosis

1. Examination: a swollen belly with dullness on tapping the sides that shifts when you roll over.
2. Ultrasound: confirms fluid, even small amounts, and assesses the liver and its blood flow.
3. Diagnostic paracentesis: a thin needle removes a small sample of fluid under local anesthetic. Tests include: - Serum-ascites albumin gradient (SAAG): 1.1 g/dL or higher points to portal hypertension (cirrhosis, heart failure). Lower values point to cancer, TB, pancreatitis or nephrotic syndrome. - Cell count: 250 or more neutrophils per cubic millimeter diagnoses spontaneous bacterial peritonitis. - total protein, culture, and cytology for cancer cells
4. Blood tests: liver function, albumin, kidney function, clotting and sodium.

Treatment

Salt restriction

Limit sodium to about 2,000 mg (2 g) a day. Fluid restriction is only needed if blood sodium is low.

Diuretics

Spironolactone, often combined with furosemide, helps the kidneys remove salt and water. Daily weight checks guide treatment. Target weight loss is about 0.5 kg (1 lb) a day without leg swelling. Doctors monitor kidney function and potassium closely.

Paracentesis

Large-volume paracentesis drains several liters in one session for tense or diuretic-resistant ascites. Albumin is given intravenously when more than 5 liters are removed, to protect the kidneys and circulation.

Refractory ascites

• TIPS (transjugular intrahepatic portosystemic shunt): a stent placed through the liver to lower portal pressure. It reduces fluid reaccumulation but can worsen confusion (hepatic encephalopathy).
• Indwelling drains for malignant ascites or palliative care.
• Liver transplant: the definitive treatment for cirrhosis with ascites.

Things to avoid

NSAIDs such as ibuprofen and naproxen can cause kidney failure and diuretic resistance in people with cirrhosis and ascites. Alcohol must be stopped completely in alcohol-related liver disease.

Complications

• Spontaneous bacterial peritonitis: infection of the fluid, causing fever, belly pain or simply confusion. It needs urgent antibiotics. People who have had it, or who have low-protein ascites, may take preventive antibiotics.
• Hepatorenal syndrome: kidney failure from cirrhosis.
• Low sodium (hyponatremia).
• Umbilical hernias.
• Fluid around the lungs (hepatic hydrothorax).

Outlook

In cirrhosis, the onset of ascites marks decompensated liver disease, and about half of people die within roughly 2 to 5 years without a transplant. Referral to a liver transplant center is recommended. The outlook in other causes depends on the underlying illness: ascites from heart failure or nephrotic syndrome can resolve with treatment, while malignant ascites usually indicates advanced cancer.

Frequently asked questions

What is ascites?

Ascites is fluid collecting in the abdominal cavity, causing the belly to swell. It is most often caused by cirrhosis of the liver, but also by heart failure, cancer, kidney disease and infections such as tuberculosis.

Is ascites a sign of dying?

Not necessarily, but it is a sign of serious illness. In cirrhosis, it indicates advanced liver disease and is a reason for transplant assessment. Ascites from heart failure or nephrotic syndrome can improve with treatment. Malignant ascites usually indicates advanced cancer.

How is fluid drained from the abdomen?

A doctor numbs the skin and inserts a thin needle or tube into the belly, usually guided by ultrasound, and lets the fluid drain into a bag. This is called paracentesis. It takes 30 minutes to a few hours and is usually done as an outpatient.

Can ascites go away on its own?

Rarely. Ascites usually needs treatment of the cause plus salt restriction and diuretics. Mild ascites can resolve if the underlying condition improves, such as stopping alcohol in alcohol-related liver disease or treating heart failure.

How can I tell ascites from bloating or belly fat?

Ascites causes steady, progressive swelling with a tight belly, rapid weight gain and often a bulging navel and ankle swelling. Bloating comes and goes with meals. Belly fat develops slowly and feels soft. An ultrasound confirms ascites.