Ascitic Fluid Lactoferrin Investigated in Liver Cirrhosis Patients

Although elevated levels of lactoferrin provide a biomarker for inflammatory bowel diseases and colorectal cancer, the clinical significance of these elevated levels in ascitic fluid of patients with ascites caused by liver cirrhosis is limited.

The usefulness of ascitic fluid lactoferrin levels for the diagnosis of spontaneous bacterial peritonitis (SBP) in patients with cirrhosis has been investigated and the association between lactoferrin levels and the development of hepatocellular carcinoma (HCC) has been evaluated.

Doctors at the Gyeongsang National University Hospital (Jinju City, South Korea) consecutively enrolled 102 patients with ascites caused by cirrhosis were from December 2008 to December 2011. Liver cirrhosis was defined by the presence of portal hypertension manifested as splenomegaly, varices, ascites, or hepatic encephalopathy, with compatible findings on diagnostic imaging, in combination with thrombocytopenia of less than 100,000/μL). The diagnosis of SBP was based on a polymorphonuclear cells (PMN) count ≥250 cells/mm3 in ascitic fluid, with or without a positive ascitic fluid or blood culture.

Laboratory tests were performed for anti-hepatitis C virus (HCV), hepatitis B virus surface antigen (HBsAg), anti-hepatitis B virus surface antibody (anti-HBs), white blood cell (WBC) count, hemoglobin level, platelet count, prothrombin time- international normalized ratio (PT-INR), total bilirubin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma glutamyl transpeptidase, serum albumin, creatinine, CRP, and ascitic fluid analysis, including WBC count, PMN count, and albumin levels.

The lactoferrin level in ascitic fluid was quantified using a human lactoferrin enzyme-linked immunosorbent assay kit (Bethyl Laboratories, Inc., Tokyo, Japan). This kit, designed as a sandwich ELISA, captures human lactoferrin present in samples by anti-lactoferrin antibody that has been pre-adsorbed on the surface of polystyrene microtiter wells.

The scientists found that the median ascitic fluid lactoferrin levels were significantly higher in patients with SBP than in those without SBP (112.7 ng/mL versus 0.6 ng/mL). The area under the receiver operator characteristic curve for the diagnosis of SBP was 0.898 with a sensitivity and specificity for a cut-off level of 51.4 ng/mL of 95.8 % and 74.4 %, respectively. Moreover, the incidence of HCC in the 78 patients without SBP was significantly higher in patients with high ascitic fluid lactoferrin levels (≥35 ng/mL) than in those with low ascitic fluid lactoferrin level (<35 ng/mL).

The authors concluded that ascitic fluid lactoferrin level can be a useful diagnostic tool to identify SBP in patients with ascites caused by cirrhosis and elevated ascitic fluid lactoferrin level in patients without SBP may be indicative of a developing hepatocellular carcinoma. The study was published on October 13, 2016, in the journal BMC Gastroenterology.

Related Links:
Gyeongsang National University Hospital
Bethyl Laboratories