Study Of Role of Novel Biomarkers for Early Detection of SBP

Background: Spontaneous bacterial peritonitis (SBP) is a life-threatening complication in cases with liver cirrhosis and ascites. Diagnostic paracentesis is the gold standard for identifying SBP, but it is invasive and resource-intensive. There is a growing interest in finding reliable non-invasive biomarkers to predict SBP early and improve patient outcomes. Objectives: This study aimed to evaluate the utility of the neutrophil-to-albumin ratio (NAR), mean platelet volume (MPV), and their ascitic fluid (AF) counterparts as predictive markers for SBP in cases with liver cirrhosis and ascites. Methods: A prospective study that was conducted on cirrhotic cases with ascites at Minia University Hospital from October 2024 to April 2025. Patients were divided into three groups: culture positive SBP, culture negative SBP, and non-SBP. Clinical, biochemical, hematological analysis, and abdominal ultrasound were conducted. Neutrophil-to-albumin ratios and MPV were calculated from blood and ascitic fluid samples. Results: MPV and NAR were significantly higher in SBP cases, particularly those with culture positive ascites. MPV demonstrated superior diagnostic performance (AUC = 0.80, cut-off >8.15 fL) compared to the blood NAR (AUC = 0.61, cut-off >25). In ascitic fluid, the neutrophil count-to-albumin ratio (AUC = 0.96, cut-off >135.17) outperformed the neutrophil percentage-to-albumin ratio (NPAR) (AUC = 0.60). Both MPV and NAR showed significant positive correlations with inflammatory and liver dysfunction markers, supporting their role as effective indicators of SBP. Conclusion: MPV and neutrophil-to-albumin ratios are promising noninvasive biomarkers for the early prediction of SBP in cirrhotic cases. Their integration into clinical practice may reduce reliance on invasive procedures and enhance timely intervention.