[The significance of 8-hydroxy-deoxyguanosine acid in the diagnosis of nonalcoholic steatohepatitis].

Objective: To evaluate the significance of serum 8-hydroxy-deoxyguanosine acid(8-OHdG) in the diagnosis of nonalcoholic steatohepatitis (NASH). Methods: Patients or healthy subjects were enrolled at the Second Hospital of Tianjin Medical University and the Second People's Hospital of Tianjin from May 2013 to December 2015. A total of 41 patients with nonalcoholic fatty liver disease were enrolled in the study, including 20 nonalcoholic simple fatty liver (NAFL) patients and 21 NASH patients whose diagnosis were proven by liver biopsy. The other 32 healthy subjects were studied as controls. Serum 8-OHdG, ALT, AST and GGT were tested. Nonalcoholic fatty liver disease activity score (NAS) and expression of 8-OHdG in liver was investigated between NAFL patients and NASH patients. The correlations between serum 8-OHdG and serum ALT, AST, GGT, and 8-OHdG in liver tissue in NASH group were investigated. In addition, the receiver operating characteristic (ROC) curve analyses for ALT and 8-OHdG levels were performed in NAFL patients and NASH patients, and the cut-off value was determined. Results: Serum 8-OHdG values in healthy controls, NAFL and NASH patients were (0.19±0.16) µg/L, (0.22±0.16) µg/L, (0.42±0.21) µg/L respectively. The serum 8-OHdG and serum ALT, GGT and 8-OHdG in liver tissue were all positively correlated in NASH group with respective correlation coefficient r values as 0.454 7, 0.382 9, and 0.497 6. AUC of 8-OHdG was 0.901 with cut-off value 0.39 µg/L. Its sensitivity was 88.3% and specificity was 81.5%, which were higher than those of ALT. Conclusion: The value of serum 8-OHdG would be used as a marker for the diagnosis of NASH.