Soluble forms of extracellular cytokeratin 18 may differentiate simple steatosis from nonalcoholic steatohepatitis

AIM: To investigate whether serum levels of two soluble forms of extracellular cytokeratin 18 (M30-antigen and M65-antigen) may differentiate nonalcoholic steatohepatitis (NASH) from simple steatosis in patients with nonalcoholic fatty liver disease (NAFLD). METHODS: A total of 83 patients with suspected NAFLD and 49 healthy volunteers were investigated. Patients with suspected NAFLD were classified according to their liver histology into four groups: definitive NASH (n = 45), borderline NASH (n = 24), simple fatty liver (n = 9), and normal tissue (n = 5). Serum levels of caspase-3 generated cytokeratin-18 fragments (M30-antigen) and total cytokeratin-18 (M65-antigen) were determined by ELISA. RESULTS: Levels of M30-antigen and M65-antigen were significantly higher in patients with definitive NASH compared to the other groups. An abnormal value (> 121.60 IU/L) of M30-antigen yielded a 60.0% sensitivity and a 97.4% specificity for the diagnosis of NASH. Sensitivity and specificity of an abnormal M65-antigen level (> 243.82 IU/L) for the diagnosis of NASH were 68.9% and 81.6%, respectively. Among patients with NAFLD, M30-antigen and M65-antigen levels distinguished between advanced fibrosis and early-stage fibrosis with a sensitivity of 64.7% and 70.6%, and a specificity of 77.3% and 71.2%, respectively. CONCLUSION: Serum levels of M30-antigen and M65-antigen may be of clinical usefulness to identify patients with NASH. Further studies are mandatory to better assess the role of these apoptonecrotic biomarkers in NAFLD pathophysiology.

Evaluation of leukocyte esterase and nitrite strip tests to detect spontaneous bacterial peritonitis in cirrhotic patients

AIM： To investigate the diagnostic efficacy of leukocyte esterase and nitrite reagent strips for bedside diagnosis of spontaneous bacterial peritonitis （SBP）. METHODS： A total of 63 consecutive patients with cirrhotic ascites （38 male, 25 female） tested between April 2005 and July 2006 were included in the study. Bedside reagent strip testing was performed on ascitic fluid and the results compared to manual cell counting and ascitic fluid culture. SBP was defined as having a polymorphonuclear ascites count of ≥ 250/mm^3. RESULTS： Fifteen samples showed SBP. The sensitivity, specificity, positive and negative predictive values of the leukocyte esterase reagent strips were; 93%, 100%, 100%, and 98%, respectively. The sensitivity, specificity, positive and negative predictive value of the nitrite reagent strips were 13%, 93%, 40%, and 77%, respectively. The combination of leukocyte esterase and nitrite reagents strips did not yield statistically significant effects on diagnostic accuracy. CONCLUSION： Leukocyte esterase reagent strips may provide a rapid, bedside diagnostic test for SBP.

Clinical significance of activity of ALT enzyme in patients with hepatitis C virus

AIM: To investigate serum alanine aminotransferase (ALT) levels in relation to the clinical,biochemical,ultrasonographic and histological characteristics of patients with hepatitis C virus. METHODS: Duration of disease,HCV-RNA,liver steatosis,and the hepatitis activity index (HAI) were correlated with serum ALT in 36 patients with HCV. ALT values were also investigated in 16 control subjects without any liver diseases. RESULTS: In bivariate analyses,ALT levels correlated with duration of HCV infection (P < 0.01),HCV-RNA (P < 0.05),and the HAI (P < 0.01). Among the components of the HAI,ALT concentrations were significantly associated with periportal bridging/necrosis (P < 0.01) and fibrosis (P < 0.05). In multivariate analysis,periportal bridging/ necrosis (β = 0.508; P < 0.01),duration of HCV infection (β = 0.413; P < 0.01),and HCV-RNA (β = 0.253; P < 0.05) were independently associated with ALT activity. The normal ALT activity for men and women was < 23 IU/L and < 22 IU/L,respectively. CONCLUSION: In patients with HCV,alterations in the liver tissue as reflected by ALT elevation are mainly associated with periportal bridging/necrosis,viral load and duration of disease. A cut-off value < 23 IU/L distinguished with high diagnostic accuracy healthy controls from patients with HCV.