Background: Cytokines play a key role in the regulation of cells of the immune system and also have been implicated in the pathogenesis of malignant diseases.
Method and patients: We studied tumor necrosis factor-alpha, tumor necrosis factor receptor and C-reactive protein levels in both ascitic fluid and serum in patients with spontaneous bacterial peritonitis (SBP) (n = 22), and in the malignant (n = 38) and cirrhotic (n = 32) ascites.
Results: C-reactive protein, tumor necrosis factor-alpha and tumor necrosis factor receptor levels in the ascitic fluid were found to be elevated in the SBP (p < 0.001) and malignant groups (p < 0.005) when compared with the sterile cirrhotic group. C-reactive protein levels in the serum were found to be elevated in the SBP group when compared with the sterile cirrhotic (p < 0.001) and malignant group (p < 0.005). Tumor necrosis factor-alpha in the serum was significantly elevated in the SBP when compared with the cirrhotic (p < 0.005) and malignant ascites (p < 0.001). Sensitivity and specificity of ascitic fluid CRP in discriminating malignant 84% and 67% and SBP from sterile ascites were 90% and 76%, respectively. Sensitivity and specificity of ascitic fluid TNF-alpha in discriminating malignant 77% and 60% and SBP from sterile ascites were 82% and 66%, respectively. Sensitivity and specificity of TNF-r p60 in discriminating malignant 74% and 70% and SBP from sterile ascites were 80% and 76%, respectively.
Conclusion: The sensitivity and specificity of ascitic fluid CRP, TNF-alpha and TNF-r values were found to be similar. Ascitic fluid Creactive protein to differentiate SBP and malignant ascitic from cirrhotic ascites are cheap, practical and safe tests used in the differential diagnosis of ascites.