AFP and infection: A low SAAG suggests other causes of normal portal pressure, such as infection or malignancy [25]. While SAAG is the first index to classify ascites, total ascitic fluid protein (AFP) is a second-line test, first to differentiate spontaneous (SBP) from secondary bacterial peritonitis, second to predict those at a high risk of SBP based on a low AFP and finally, to suggest heart failure in patients with high SAAG ascites [19,26].