Transferrin and the prediction of spontaneous bacterial peritonitis

ABSTRACT

Patients with advanced liver disease are particularly susceptible to spontaneous bacterial peritonitis [SBP]. Pathogenic micro-organisms could survive and become more virulent in the presence of free iron. Thus, iron binding proteins provide protection against these organisms. The present study was conducted to evaluate the role of determining transferrin levels in serum and ascitic fluid, as well as its serum ascitic fluid ratio [mg/mg] in differentiating between SBP and SA [sterile ascites] in cirrhotic patients. Moreover, the role of the ratio between ascitic fluid transferrin ascitic fluid total protein [mg/g], as a marker for SBP was tested. Our study included 50 patients. Twenty five patients had SBP [according to Runyon's and Hoefs criteria] while the other 25 patients had SA. Our results revealed that patients with advanced liver impairment had higher susceptibility for SBP than SA. They had significantly higher serum total bilirubin [p<0.001] and significantly lower serum albumin and transferrmn [p<0.001, respectively]. More over, SBP group had significant prolongation of the prothrombin time [p<0.001]. Ascitic fluid aspirated from the SBP patients showed significantly lower transferrin and total protein values [p<0.05 and <0.001, respectively]. Serum ascitic fluid transferrin ratio [mg/mg] was significantly lower in patients with SBP [p<0.001]. The best cut off level giving the highest diagnostic sensitivity and specificity was 3.5 yet, at this level poor diagnostic sensitivity and specificity in differentiating between the two clinical conditions [76% and 28%, respectively] was found. Ascitic fluid transferrin ascitic fluid total protein ratio [mg/g] was significantly higher in patients with SBP [p<0.001] and had a diagnostic sensitivity and specificity of 100%, respectively in differentiating between both clinical conditions at a cut-off level of 22.26. Patients with advanced liver disease are more liable for the occurrence of SBP than SA. Ascitic fluid transferrin ascitic fluid total protein ratio, at a cut-off level of 22.26, can differentiate between the two clinical conditions with a diagnostic sensitivity and specificity of 100%, respectively