ASCITIC/ PERITONEAL FLUID ANALYSIS
Pre-test preparation or requirements
Significance of test
SERUM-ASCITES ALBUMIN GRADIENT (SAAG) Serum albumin- Ascitic albumin
SAAG is generally low (<1.1 g/dL) in ascites not due to portal hypertension, as in cases of infection or malignanc. SAAG is high (≥1.1 g/dL) in portal hypertension-related ascites, as in cases of liver cirrhosis or congestive heart failure.
Sugar mg/dl 60 100
Peritoneal fluid has been classified on the basis of the total protein (TP) content into either an exudate or transudate, attempting to reflect the different processes of fluid formation. The cut-off values used have varied but mostly lie between 2.5 and 3.0 g/dl.
Serum-ascites albumin gradient (SAAG) is generally low (<1.1 g/dL) in ascites not due to portal hypertension, as in cases of infection or malignancy (not due to portal hypertension). SAAG is high (≥1.1 g/dL) in portal hypertension-related ascites, as in cases of liver cirrhosis or congestive heart failure.
The concentration of glucose in the ascitic fluid, under normal conditions, is similar to that in the serum. However, ascitic glucose concentration decreases due to consumption by bacteria, white blood cells or cancer cells in the fluid in tuberculous peritonitis, spontaneous bacterial peritonitis (SBP), and malignancy. Ascitic glucose concentration is often significantly lower than normal in tuberculous ascites, which makes it an indicator in differentiating tuberculosis from other diseases, such as cirrhosis. The ascitic/blood glucose ratio is a useful test in the differentiation of tuberculous peritonitis from ascites due to other causes.