Value of Different Diagnostic Markers in Spontaneous Bacterial Peritonitis in HCV Egyptian Cirrhotic Patients

Abstract

Background: Spontaneous bacterial peritonitis (SBP) is a life-threatening infection occurring in 8% - 30% of ascitic cirrhotic patients; different laboratory diagnostics play a pivotal role for rapid and effective management of SBP patients. Polymorphonuclear leucocytic (PMNLs) count in Ascitic fluid (AF) is the mainstay for the diagnosis, whereas the diagnostic role of alternative biomarkers is rather controversial. In many studies, serum lipopolysaccharide binding protein (LBP) was elevated and Complement 3 (C3) level was significantly consumed in AF of SBP patients. Objectives: To evaluate the diagnostic value of serum LBP and AF C3 in HCV-cirrhotics with SBP in relation to other well-established serum and AF markers. Patients and Methods: One hundred and twenty patients with HCV-cirrhosis and ascites were enrolled and consented: 50 patients with non-SBP ascites in group A and 70 ascitic patients diagnosed with SBP according to clinical suspicion and PMLs count in AF ≥ 250 cells/mm3 in group B in addition to 15 healthy individuals considered as a control group. Serum LBP, CBC, kidney and liver function tests, CRP, fasting and 2 h PP blood glucose and HCV antibodies were measured. AF samples were sent for C3 level, culture, PMNLs count, LDH, CRP, total proteins and albumin. Results: In patients with SBP, the level of serum LBP was not significantly high (p > 0.05) with best cut off value at 0.4500 and poor AUC (<0.6) with low sensitivity and specificity (53.3% & 57.7%, respectively). AF C3 was significantly reduced in AF (p < 0.001) with best cut off value at 144.2 and almost excellent AUC (0.889) with good sensitivity and specificity (82% & 84%, respectively). AF culture showed significant difference between both patients groups (p < 0.05) but with low sensitivity (33.3%). Serum and AF CRP and AF PMNLs count were of high significance in SBP diagnosis (p < 0.001). Conclusion: Serum LBP level showed low significance while AF C3 was significantly reduced in patients with SBP. AF culture showed significant difference between both groups but with low sensitivity while serum, AF levels of CRP and AF PMNLs count were highly significant, and the latter is still considered the gold standard for SBP diagnosis.