SAAG (Serum Ascites Albumin Gap)

Specimen Required

Ascitic Fluid & 4cc Clotted Blood

Fasting Required

Purpose of the Test

SAAG testing is ordered when a person presents with signs and symptoms of ascites, such as abdominal swelling, weight gain, and discomfort. The test is used to determine the underlying cause of ascites and to differentiate between two major types of ascites: transudative and exudative.

When this test is required

SAAG is requested when a patient presents with symptoms of ascites, such as abdominal swelling or distension, nausea, and vomiting. It is also ordered when liver disease is suspected, such as in patients with a history of alcohol abuse, hepatitis, or jaundice.

What the Test Detects

The serum-ascites albumin gradient (SAAG) is a diagnostic tool used to differentiate the causes of ascites (fluid accumulation in the abdominal cavity) by measuring the difference in albumin concentration between the serum (blood) and ascitic fluid (fluid in the abdominal cavity).

Preparation for the Test

There is no specific preparation required for SAAG testing. However, your healthcare provider may provide instructions on how to prepare for the procedure, such as avoiding eating or drinking for a certain period before the test.

Sample Requirements

SAAG testing requires a blood sample and a sample of fluid from the abdominal cavity (ascitic fluid). The blood sample is usually collected from a vein in the arm, while the ascitic fluid sample is obtained by inserting a needle into the abdomen and drawing out the fluid.

Additional Notes

A SAAG level of = 1.1 g/dL indicates portal hypertension as the underlying cause of ascites, while a level of < 1.1 g/dL suggests a non-portal hypertensive cause. It is important to note that other tests, such as imaging studies and biopsies, may be needed to confirm the underlying cause of ascites.

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