Description
Why It’s Done:
The test is performed to:
• Diagnose the cause of fluid accumulation in body cavities (e.g., pleural effusion, ascites).
• Differentiate between transudate and exudate fluid types.
• Help identify conditions such as:
o Heart failure
o Liver cirrhosis
o Kidney disease
o Infections
o Cancer
o Autoimmune disorders
In peritoneal fluid, the serum-ascites albumin gradient (SAAG) is often calculated using this test to assess the cause of ascites.
Preparation:
• No special preparation is typically required for the patient.
• A sample of fluid is collected via:
o Thoracentesis (for pleural fluid)
o Paracentesis (for peritoneal fluid)
o Lumbar puncture (for cerebrospinal fluid)
• You may be asked to sign a consent form before the procedure.
• Inform your doctor if you are taking any medications or have bleeding disorders


