Ascites is a pathological collection of fluid in the peritoneal cavity. The most common cause is cirrhosis, accounting for approximately 75% of cases.
Patients present with abdominal distension; fluid may be detected on physical examination with shifting dullness. Ultrasound, computed tomography scan, or magnetic resonance imaging can confirm the diagnosis. In the majority of patients, history and examination will provide important clues as to the aetiology of ascites (e.g., signs of chronic liver disease or cardiac failure). Causes include diseases that lead to portal hypertension, hypo-albuminaemia, and neoplasms.
In 2017, cirrhosis caused more than 1.32 million deaths globally, compared with fewer than 899,000 deaths in 1990. Deaths due to cirrhosis constituted 2.4% of total deaths globally in 2017 compared with 1.9% in 1990.
In cirrhosis, ascites forms due to renal dysfunction and abnormalities in portal and splanchnic circulation. Sodium retention is a major factor in pathogenesis. Splanchnic arterial vasodilatation (secondary to hepatic fibrosis) leads to increased lymph formation, activation of the renin angiotensin system and sympathetic nervous system, and release of antidiuretic hormone. This causes renal sodium and water retention. There is increased resistance to portal flow resulting in portal hypertension, collateral vein formation, and shunting of blood to the systemic circulation. About 50% of patients with cirrhosis develop ascites within 10 years.
Other causes of portal hypertension that may be associated with ascites include congestive heart failure, constrictive pericarditis, alcoholic liver disease, fulminant hepatitis, subacute hepatitis, massive liver metastasis, and Budd-Chiari syndrome.
Conditions causing hypo-albuminaemia such as nephrotic syndrome and protein-losing enteropathy may result in ascites. Peritoneal diseases including infectious peritonitis and malignancies can also cause ascites.
- Hepatitis C
- Alcoholic liver disease
- Congestive heart failure
- Nephrotic syndrome
- Hepatitis B
- Primary biliary cholangitis
- Autoimmune hepatitis
- Wilson's disease
- Constrictive pericarditis
- Budd-Chiari syndrome
- Chronic renal failure
- Protein-losing enteropathy
- Peritoneal carcinomatosis
- Systemic lupus erythematosus
- Fulminant hepatic failure
- Hepatic metastases
- Secondary peritonitis
- Chylous ascites
- Urogenital surgical trauma
- Bile ascites
- Ovarian tumours
- Tricuspid regurgitation
- Guidelines on the management of ascites in cirrhosis
- Diagnosis, evaluation, and management of ascites, spontaneous bacterial peritonitis and hepatorenal syndrome: 2021 Practice Guidance by the American Association for the Study of Liver Diseases
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