Ascites

• • Pathologic accumulation of free fluid within the abdominal cavity

  • Ascites develops from

  • -Decreased plasma oncotic pressure (liver disease, malnutrition)

    -Increased lymph/peritoneal fluid production (liver disease, malignant ascites)

    -Blockage or disruption of abdominal lymphatic drainage (chylous ascites, congenital)

  • Patients typically complain of abdominal distention or vague constitutional symptoms

Epidemiology

• • Over 80% of patients with ascites have portal hypertension secondary to chronic liver diseases

  • Less common causes are chylous, malignant, or pancreatic ascites

  • Chylous ascites is most commonly due to occult tumor obstructing the lymphatic ducts (lymphoma or adenocarcinoma), external trauma, operative disruption, or congenital anomalies

  • Malignant ascites occurs secondary to peritoneal implants stimulating ascitic fluid production or if there is advanced venous or lymphatic obstruction

Symptoms and Signs

• • Vague, diffuse, constant abdominal discomfort associated with distention

  • Ascites from cirrhosis associated with systemic signs of liver disease including palmar erythema, spider angiomas, gynecomastia, evidence of portosystemic shunting, and encephalopathy

  • Malignant ascites associated with weight loss, a history of cancer, or symptoms related to the neoplasm (eg, fever, night sweats, and weight loss in cases of lymphoma)

  • Chylous ascites often relatively asymptomatic with vague abdominal discomfort and mild abdominal distention

Laboratory Findings

Liver Failure

• • Systemic

  • -Hypoalbuminemia

    -Increased bilirubin

    -Increased prothrombin time/international normalized ratio (PT/INR)

  • Paracentesis

  • -Serum-ascites albumin

    -Gradient > 1.1

Chylous Ascites

• • Systemic

  • -Hypoalbuminemia

    -Lymphocytopenia

    -Anemia

  • Paracentesis

  • -Grossly milky appearance

    -Serum-ascites albumin gradient (SAAG) < 1.1

    -Triglyceride level > 200 mg/dL

    -Leukocyte count > 1000/µL

Malignant Ascites

• • Systemic

  • -Positive tumor markers

    -Evidence of malnutrition

  • Paracentesis

  • -Positive cytologic diagnosis

    -Aneuploidy (flow cytometry)

    -High lactic dehydrogenase (LDH) (> 500 IU/L)

    -High carcinoembryonic antigen (CEA)

Imaging Findings

• • Abdominal US verifies the presence of ascites, suggests the presence of liver disease, and guides diagnostic/therapeutic paracentesis

  • Abdominal/pelvic CT scans are useful in documenting ascites; suggesting liver disease; detecting lymphadenopathy and masses of the mesentery as well as of solid organs, such as the liver, ovaries, and pancreas

• • Portal hypertension

  • Chylous ascites

  • Malignant ascites

  • Normal postoperative intra-abdominal fluid

  • Sterile fluid collection

  • Intra-abdominal abscess

  • Hematoma

  • Biloma

  • Urinoma

  • Soft-tissue neoplasm

  • Chronic inflammatory peritonitis

Rule Out

• • Spontaneous bacterial peritonitis (SBP)

  • Underlying malignancy

• • Diagnostic paracentesis: LDH level, albumin, amylase, triglyceride level, WBC count, cytologic studies, Gram stain, and culture

  • Abdominal/pelvic CT scan:

  • -Plus a full colonoscopy to search for primary neoplasm in malignant ascites

    -Used to search for underlying neoplasm in cases of chylous ascites occurring in adults with constitutional symptoms

When to Admit

• • Cirrhotic patients with an exacerbation of ascites should be admitted to ...