Ascites
Basics
Description
- Ascites is the pathologic accumulation of fluid in the peritoneal cavity and the most common complication of cirrhosis (1).
- It may occur in conditions that cause generalized edema like nephrotic syndrome, heart failure, and malignancy.
- Amount of fluid accumulation:
- Grade 1: mild ascites—only detected by ultrasound (US); responsive ascites
- Grade 2: moderate ascites—moderate symmetric distension of abdomen; recurrent ascites
- Grade 3: large or gross ascites—marked distension of the abdomen; refractory ascites (RA)
- Ascitic fluid that recurs after paracentesis or cannot be prevented by treatment
- Men generally have no fluid in peritoneal cavity; women may have up to 20 mL depending on menstrual phase.
Epidemiology
- Children: most commonly associated with nephrotic syndrome and malignancy
- Adults: cirrhosis (81%), cancer (10%), heart failure (3%), tuberculosis (TB) 2%, other (6%)
- 50% of patients with decompensated cirrhosis develop ascites.
Incidence
Approximately 50–60% of cirrhotic patients develop ascites within 10 years (2). The presence of ascites in cirrhotic patients is a poor prognostic indicator with mortality of about 44% in 5 years (1).
Prevalence
10% of patients with cirrhosis have ascites.
Etiology and Pathophysiology
- Portal hypertension versus nonportal hypertension
- Cannot reliably establish/confirm etiology without paracentesis
- Serum-ascites albumin gradient (SAAG): (serum albumin level: ascites albumin level) helps to differentiate
- High portal pressure (SAAG ≥1.1 g/dL)—reflects portal hypertension
- Cirrhosis, hepatitis (alcoholic, viral, autoimmune, medications), acute liver failure, liver malignancy (primary or metastatic), heart failure or constrictive pericarditis, Budd-Chiari syndrome, and portal vein thrombosis
- Normal portal pressure (SAAG <1.1 g/dL)—excludes portal hypertension
- Peritoneal carcinomatosis, TB, severe hypoalbuminemia (nephrotic syndrome; severe enteropathy with protein loss), Meigs syndrome (ovarian cancer), lymphatic leak (chylous ascites), pancreatitis, inflammatory (vasculitis, lupus serositis, sarcoidosis), other infections (parasitic, fungal), hemoperitoneum (trauma or ectopic pregnancy)
- Pathogenesis of ascites in the setting of portal hypertension (cirrhotic ascites): backward transmission of increased pressure to the visceral capillary bed with subsequent dilation and shift of fluid to the peritoneal cavity
- This decreases intravascular volume and leads to hypotension. Systemic hypovolemia triggers renin-angiotensin–aldosterone system.
Risk Factors
- Cirrhosis—hepatitis B and C; alcohol abuse
- Congestive heart failure (CHF); advanced kidney disease; malignancy
- TB
General Prevention
Lifestyle—appropriate diet; physical activity; safe sexual practices; avoid alcohol misuse and hepatotoxic medications.
Commonly Associated Conditions
Nephrotic syndrome, liver cancer, heart failure
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Citation
Domino, Frank J., et al., editors. "Ascites." 5-Minute Clinical Consult, 33rd ed., Wolters Kluwer, 2025. Medicine Central, im.unboundmedicine.com/medicine/view/5-Minute-Clinical-Consult/1688600/all/Ascites.
Ascites. In: Domino FJF, Baldor RAR, Golding JJ, et al, eds. 5-Minute Clinical Consult. Wolters Kluwer; 2025. https://im.unboundmedicine.com/medicine/view/5-Minute-Clinical-Consult/1688600/all/Ascites. Accessed December 10, 2024.
Ascites. (2025). In Domino, F. J., Baldor, R. A., Golding, J., & Stephens, M. B. (Eds.), 5-Minute Clinical Consult (33rd ed.). Wolters Kluwer. https://im.unboundmedicine.com/medicine/view/5-Minute-Clinical-Consult/1688600/all/Ascites
Ascites [Internet]. In: Domino FJF, Baldor RAR, Golding JJ, Stephens MBM, editors. 5-Minute Clinical Consult. Wolters Kluwer; 2025. [cited 2024 December 10]. Available from: https://im.unboundmedicine.com/medicine/view/5-Minute-Clinical-Consult/1688600/all/Ascites.
* Article titles in AMA citation format should be in sentence-case
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T1 - Ascites
ID - 1688600
ED - Domino,Frank J,
ED - Baldor,Robert A,
ED - Golding,Jeremy,
ED - Stephens,Mark B,
BT - 5-Minute Clinical Consult, Updating
UR - https://im.unboundmedicine.com/medicine/view/5-Minute-Clinical-Consult/1688600/all/Ascites
PB - Wolters Kluwer
ET - 33
DB - Medicine Central
DP - Unbound Medicine
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