非酒精性脂肪性肝病的临床及病理学特征

Clinical and histological features of non-alcoholic fatty liver disease

目的探讨我国成人非酒精性脂肪性肝病（NAFLD）不同ALT水平患者的临床及病理学特征。方法分析2005年1月2009年3月经肝活体组织检查证实的108例NAFLD患者的人口学、生物化学及病理学资料，并比较血清ALT正常与增高患者的病理学及临床特征。结果在108例NAFLD中，49例（45．4％）为单纯性脂肪肝（NAFL），57例（52．8％）为非酒精性脂肪性肝炎（NASH），2例（1．9％）为NASH相关肝硬化。ALT和AST水平，NASH患者分别为（156．2±137．7）U／L和（82．2±67．8）U／L，NAEL患者分别为（103．9±93．7）U／L和（52．2±33．4）U／L，t值分别为2．55和3．13，P值均〈0．01，差异有统计学意义。AST／ALT比值NASH患者为0．61±0．30，NAFL患者为0．78±0．77，NASH患者AST／ALT比值低于NAFL患者，t=2．18，P=0．03，差异有统计学意义。ALT增高组中NASH占64．9％（50／77），ALT正常组NASH占29．0％（9／31），χ^2=11．49，P=0．00。ALT增高组炎症程度显著高于ALT正常组，χ^2=10．30，P=0．01，差异有统计学意义；但肝脂肪变和纤维化程度在两组之间，χ^2=5．52，6．12；P=0．12，0．10，差异无统计学意义。ALT增高组血清AST、γ-谷氨酰转肽酶、总胆固醇、载脂蛋白Al、载脂蛋白B和收缩压水平均比ALT正常组显著增高（t值分别为5．91，2．00，2.30，2．10，3．14，2.43；P值分别为0．00，0.05，0．02，0．04，0．00，0．02），而AST／ALT比值、B超下脾脏肋间厚度则显著降低（t值分别为3．70和2．95；P值分别为0．00和0．01）。多元回归分析显示血清ALT增高与病理学NASH相关（OR=2．78，95％CI 1．06～7．3，P=0．04），但血清ALT预测NASH的准确性欠佳，ROC曲线下面积为0．69（95％CI 0．59～0．8，P=0．00）。结论在中国成人NAFLD患者中可以见到完整的疾病谱。ALT升高患者NASH比例更高，血清ALT水平可预测NAFLD患者炎症程度，但不能预测脂肪变和纤维化程度。

Objective To investigate the clinical and histological features in Chinese patients with non-alcoholic fatty liver disease （NAFLD）. Methods 108 patients with biopsy-proven NAFLD were enrolled in this study. Clinical, demographic, and biochemical data were compared between NAFLD patients with abnormal ALT and those with normal ALT. Results Simple fatty liver, nonalcoholic steatohepatitis （NASH） and cirrhosis were diagnosed in 49 （45.4%）, 57（52.7%） and 2 （1.9%） patients, respectively. ALT and AST levels of NASH group were higher than those of simple fatty liver group （t = 2.55, 3.13; P = 0.0 1, 0.00）. Fifty of the 77 patients （64.9%） with abnormal ALT levels were diagnosed as non-alcoholic steatohepatitis （NASH）, and twenty-six were diagnosed as simple fatty liver, according to liver histology. Among the 31 patients with normal ALT levels, nine （29%） had NASH and twenty-two had simple fatty liver （P = 0.130）. The patients with normal ALT had lower necroinflammatory grade than patients with abnormal ALT （ χ^2 = 10.30, P = 0.01）, but they had similar degree of steatosis and fibrosis （ χ^2= 5.52, 6.12; P = 0.12, 0.01）. AST, γ - glutamyltransferase, total cholesterol, apolipoprotein Al, apolipoprotein B and systolic blood pressure of patients with normal ALT were all lower than those of patients with abnormal ALT （t = 5.91, 2.00, 2.30, 2.10, 3.14, 2.43; P = 0.00, 0.05, 0.02, 0.047 0.00, 0.02）, while spleen thickness and AST/ALT ratio in patients with normal ALT were higher than those with abnormal ALT significantly （t = 3.70, 2.95; P = 0.00, 0.01）. Multivariate analysis revealed that ALT （OR = 2.78, 95% CI 1.06-7.3, P = 0.04） was the only independent predictor of NASH, and ALT had low accuracy in predicting NASH, the area under the receiver operating characteristics curves of ALT to predict NASH was 0.69 （95% CI 0.59-0.8, P = 0.00）. Conclusion NAFLD patients have higher ALT level, and elevated serum level of ALT is independent predictor of the degree of inflammation, but not of steatosis and fibrosis.