摘要目的探讨8-羟基脱氧鸟苷酸（8-OHdG）在非酒精性脂肪性肝炎（ NASH）诊断中的意义。方法收集2013年5月—2015年12月天津医科大学第二医院、天津市第二人民医院32例健康对照者、20例非酒精性单纯性脂肪肝（ NAFL ）和21例NASH患者空腹静脉血，检测所有受试者的8-OHdG及ALT、AST、γ-谷氨酰转移酶（ GGT）；并对所有NAFL、NASH患者行肝组织活检，对活检组织行NAFLD活动度积分（ NAS）与8-OHdG免疫组化检测。统计分析各组间上述指标的差异，并分析NASH患者血清8-OHdG与血清ALT、AST、GGT水平及肝组织中8-OHdG表达的相关性，采用ROC曲线法分析血清ALT、8-OHdG水平对NASH诊断的价值，并确定诊断界点（ cut-off值）。结果健康对照组、NAFL组、NASH组血清8-OHdG水平分别是（0.19±0.16）μg／L、（0.22±0.16）μg／L和（0.42±0.21）μg／L，NASH组血清8-OHdG水平明显高于健康对照组和NAFL组，差异有统计学意义（ P值均＜0.05）；NASH组血清8-OHdG水平与血清ALT、GGT水平及肝组织中8-OHdG表达呈正相关，r值分别为0.4547、0.3829、0.4976（ P值均＜0.05）；ROC曲线分析显示，血清8-OHdG诊断NASH的AUC为0.901，cut-off值为0.39μg／L，其灵敏度和特异度分别为88.3％和81.5％，均高于ALT。结论检测血清中8-OHdG的含量对NASH的诊断有一定意义。

abstractsObjective 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.