Background and study aim: Spontaneous bacterial peritonitis (SBP) is a serious complication of decompensated liver ‎cirrhosis. It may be presented with atypical symptoms or asymptomatic, so ascitic fluid ‎examination is recommended beside the clinical evaluation for the diagnosis of SBP. This study ‎aimed to evaluate the value of macrophage inflammatory protein Ib (MIP Ib) and platelet ‎indices as diagnostic markers for spontaneous bacterial peritonitis‎.
Patients and Method: ‎This is a cross-sectional study comprised 75 cirrhotic patients. Patients were divided into two ‎groups according to the presence of ascites: group I: Comprising 50 cirrhotic patients with ‎ascites who were classified into: group Ia comprising 25 patients with SBP, group Ib ‎comprising 25 without SBP, and group II: Comprising 25 cirrhotic patients without ascites ‎with other bacterial infections. All patients were subjected to history taking, full clinical ‎examination, ultrasonographic examination; laboratory investigation (complete blood count ‎‎(CBC), liver, and kidney function tests and serum C reactive protein (CRP)), Diagnostic ‎paracentesis and ascetic fluid examination were done for all ascitic patients. Measurement of ‎MIP Ib in serum and ascitic fluid was done‎.‎
Results: significant increases in CRP, white blood cell count, mean platelet volume (MPV) and platelet ‎distribution width (PDW), were found in SBP group compared to other groups (P<0.001). ‎Serum MIP-1b level at a cut-off value >85 pg/ml could predict presence of SBP, with a ‎sensitivity 100% and a specificity 44%. Ascitic MIP-Ib at a cut-off value of > 120 pg/ml could ‎predict the presence of SBP with sensitivity 68% and specificity 100%. Cut-off value for MPV ‎was (> 8.5 fl) could predict SBP presence, with sensitivity 76% and specificity 52%. Cut-off ‎value for PDW was (> 15 fl) could predict SBP presence, with sensitivity 84% and specificity ‎‎84%‎‎‎.
Conclusion: Serum and ascitic MIP-1β and platelets indices are useful diagnostic biomarkers for spontaneous ‎bacterial peritonitis ‎‎‎.