DIAGNOSTIC PARACENTESIS - A 2-STEP APPROACH

Diagnostic paracentesis is usually considered the first test to be per formed in the assessment of the ascitic patient and a large number of investigations on ascitic fluid have been proposed, To assess the valu e of a simplified procedure, serum to ascites albumin gradient and asc itic white blood cell counts were employed as a first step, One hundre d and fifty-three paired serum and ascitic fluid samples were analysed and allowed patients to be divided into three groups: 1) serum to asc ites albumin gradient >= 11 g/L and white blood cells < 0.5 x 10(9)/L predicted cirrhosis (or liver carcinoma) without peritonitis with 83% efficacy, 96% positive predictive value and 65% negative predictive va lue; 2) serum to ascites albumin gradient >= 11 g/L and white blood ce lls >= 0.5 x 10(9)/L predicted cirrhosis (or liver carcinoma) with per itonitis with 86% efficacy, 45% positive predictive value and 99% nega tive predictive value; 3) serum to ascites albumin gradient < 11 g/L p redicted the other diagnoses with 92% efficacy, 77% positive predictiv e value and 95% negative predictive value, As serum to ascites albumin gradient >= 11 g/L and white blood cells < 0.5 x 10(9)/L predicted ci rrhosis (or liver carcinoma) without peritonitis in 96% of the cases a nd excluded peritonitis in 99% of the cases, further fluid ascitic ana lyses could be considered as a second step only in patients with serum to ascites albumin gradient < 11 g/L and/or white blood cells >= 0.5 x 10(9)/L. In a group of ascitic patients where the prevailing diagnos is is cirrhosis (or liver carcinoma) without peritonitis, this simplif ied approach could provide a favourable cost/benefit ratio.