New Biochemical Parameters in the Differential Diagnosis of Ascitic Fluids

BACKGROUND: In the cases of ascitis, it is essential to determine their origin using the parameters obtained by the cytological and biochemical examinations. The aim of this study was to evaluate the usefulness of different biochemical markers and the number of cells in the differential diagnosis of ascitic fluid (AF). METHODS: One hundred ninety-one cases of AF were studied, who were admitted to the hospital from January 01, 2009 to December 31, 2014. One hundred fifty-two of them were included in the analysis, and the remaining 39 were excluded because they had more than one associated pathology, clotted or hemolyzed. RESULTS: The more frequent etiologies of AF were the cirrhosis (29%), the infections (22%) and the neoplasies (19%). Other pathologies reached 16%. Cutoff > 300 cells/mm(3) detected the 78% of exudates. The AF/serum (S) of aspartate aminotransferase (AST) (> 0.5), lactate dehydrogenase (LDH) (> 0.6), proteins (PT) (> 0.5), cholesterol (COL) (> 0.4), and alanine aminotransferase (ALT) (> 0.5) correctly detected 80%, 78%, 72%, 70% and 70% of the exudates, respectively. CONCLUSION: We proposed the utilization of a new cutoff of cellular counting, major of 300/mm(3), since it would allow improving the detection of exudate ascites, without including the transudate ascites. AST AF/serum ratio (AF/S) showed the major usefulness in the differentiation and characterization of AF; LDH, proteins, cholesterol and ALT might be also acceptable in the above mentioned differentiation. The serum-ascites albumin gradient (SAAG) turned out to be a good marker of portal hypertension associated with cirrhotic processes. Creatine kinase (CK), alkaline phosphatase (ALP), amylase (AMI), total bilirubin (TB), triglycerides (TG) and glucose (GLU) did not allow differentiating exudates from transudates.