Study of Ascetic Fluid Lactoferrin and Calprotectin as a Novel Diagnostic Markers in Cirrhotic Patients with Spontaneous Bacterial Peritonitis

Abstract Background Spontaneous bacterial peritonitis (SBP) is a critical infection in patients with liver cirrhosis and ascites, necessitating early diagnosis for effective intervention. The standard diagnostic criterion for SBP is an ascitic fluid polymorphonuclear leukocyte (PMN) count of ≥ 250 cells/mm³. This study explored alternative diagnostic markers for SBP, including high sensitivity C-reactive protein (hsCRP), serum procalcitonin, urinary lipocalin, ascitic lactoferrin, homocysteine, and fecal or ascitic calprotectin. Aim of the Work The aim of this study is to evaluate the diagnostic accuracy of both ascitic fluid calprotectin and lactoferrin in detecting SBP in cirrhotic patients. Patients and Methods The research was conducted at the Hepatology and Gastroenterology Department at Ain Shams University in Egypt from September 2022 to May 2023. Patient data, including demographics, clinical symptoms, laboratory results, and ascitic fluid markers (calprotectin and lactoferrin), were collected and analyzed to assess their diagnostic accuracy for SBP in cirrhotic patients. Results Among the studied population, bleeding, abdominal pain, and fever were significantly more frequent in patients with SBP than those without SBP. Patients with SBP exhibited higher levels of leucocyte count, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), bilirubin, alanine aminotransferase (ALT), and aspartate aminotransferase (AST), and lower levels of albumin compared to those without SBP. Ascitic fluid parameters, including PMN, calprotectin, and lactoferrin, were significantly higher in patients with SBP. These biomarkers also showed a positive correlation with liver disease severity and were positively correlated with white blood cell count, ESR, and CRP, while calprotectin showed a negative correlation with albumin. At a cut-off point of > 221, ascitic fluid calprotectin demonstrated a sensitivity of 92% and specificity of 96% for predicting SBP, while ascitic fluid lactoferrin, at a cut-off point of > 64.5, had a sensitivity of 92% and specificity of 80% for SBP prediction. Conclusion Both ascitic fluid calprotectin and lactoferrin were significantly elevated in cirrhotic patients with SBP compared to those without SBP. These findings suggest that ascitic fluid calprotectin and lactoferrin can serve as valuable diagnostic tests for screening and diagnosing SBP in patients with liver cirrhosis. Early detection of SBP is crucial for timely intervention and improved patient outcomes.