To distinguish between primary bacterial peritonitis from secondary peritonitis the following biochemical parameters in ascitic fluid has been used, EXCEPT:

Secondary bacterial peritonitis is the ascitic fluid infection caused by a surgically treatable intraabdominal source of infection. It can be divided into two groups 1. Those with free perforation of a viscus eg : duodenal ulcer perforation 2. Those with loculated abscess eg : perinephric abscess The characteristic ascitic fluid findings in the setting of secondary bacterial peritonitis are Ascitic fluid PMN > 250 cells/mm 3 with at least two of the following criteria 1. Ascitic fluid total protein > 1 g/dl 2. LDH greater than the upper limit of the normal of the serum 3. Glucose < 50 mg/dl If Ascitic fluid carcinoembryonic antigen (CEA) is > 5 ng/mL and alkaline phosphatase > 240 U/L indicates gut perforation. Ref: AASLD practice guidelines: Hepatology, Vol.49, No.6 , 2009.