探讨血清碱性磷酸酶(ALP)、γ-谷氨酰基转肽酶(γ-GGT)及其倍值比在胆汁淤积性肝病的鉴别价值。

拟定入选标准，收集山西医科大学第二医院消化内科、风湿免疫科、普外科2012年1月至2016年7月住院患者125例，其中药物性胆汁淤积肝损伤组(20例)、原发性胆汁性胆管炎(PBC)组(50例)、胆总管结石组(55例)。采用速率法检测血清ALP、GGT水平。绘制受试者工作曲线(ROC)，分析ALP、GGT、(ALP实测值/ALP正常值上限)/(GGT实测值/GGT正常值上限)(ALP^×/GGT^×)用于药物性胆汁淤积性肝损伤、PBC、胆总管结石的鉴别诊断效果。所有入组患者均签署知情同意书，经医院伦理委员会研究通过。

各组间血清ALP水平差异无统计学意义(F＝0.27，P>0.05)；各组间血清GGT水平差异有统计学意义(F＝9.44，P<0.05)；药物性淤胆组与PBC组血清GGT水平差异无统计学意义(q＝2.52，P>0.05)，胆总管结石组[(424.7±317.0)U/L]高于药物性胆汁淤积组[(152.2±51.0)U/L]和PBC组[(230.5±121.0)U/L]，差异有统计学意义(q＝10.2，8.3；P<0.05)。各组间ALP^×/GGT^×值比较差异有统计学意义(F＝8.23，P<0.05)，药物性淤胆组(0.95±0.54)大于PBC组(0.64±0.33)和胆总管结石组(0.37±0.18)，PBC组大于胆总管结石组，差异均有统计学意义(q＝4.2，6.4，5.6；P<0.05)。ALP、GGT和ALP^×/GGT^×的ROC曲线显示：药物性胆汁淤积(阳性组表示为＋)与胆总管结石性胆汁淤积(阴性组表示为－)ROC曲线下面积分别为0.552，0.189和0.972，PBC(＋)与胆总管结石性胆汁淤积(－)ROC曲线下面积分别为0.498，0.298和0.749，药物性胆汁淤积(＋)与PBC(－)的ROC曲线下面积分别为0.645，0.319和0.741；ALP^×/GGT^×曲线下面积最大。ALP^×/GGT^×用于鉴别胆汁淤积性肝病的敏感度、特异度优于ALP、GGT，鉴别诊断药物性胆汁淤积与PBC的敏感度和特异度为90.9%和62.0%；鉴别诊断药物性胆汁淤积与胆总管结石的敏感度和特异度为100.0%和84.6%；鉴别诊断PBC与胆总管结石的敏感和特异度为100.0%和38.5%；对应的cut－off值分别为0.599，0.534，0.225。

ALP^×/GGT^×有可能成为新的鉴别胆汁淤积性肝病的重要指标，弥补了ALP、GGT单独鉴别胆汁淤积性肝病的不足，对药物性胆汁淤积性肝病、PBC、胆总管结石鉴别诊断有重要价值。

To explore the clinical application of the detection of serum alkaline phosphatase (ALP), gamma glutamyl transpeptidase (GGT) and ALP/upper limit of normal (ULN) divided by GGT/ULN (ALP^×/GGT^×) in the differential diagnosis of the cholestatic liver disease.

Twenty patients with drug-induced cholestatic patients (drug-induced cholestatic liver disease group), 50 cases with primary biliary cholangitis [primary biliary cholangitis group(PBC)] and 55 cases with choledocholithiasis (choledocholithiasis group) were enrolled from January 2012 to July 2016, according to the diagnostic criterias respectively.ALP and GGT were examined by rate method.To compare mean differences of above makers and draw their ROC curves among groups.

There were no significant differences of ALP among groups (F=0.27, P>0.05). The differences of GGT among groups were significant (F=9.44, P<0.05). However, there was no significant difference between drug-induced cholestatic liver disease group and PBC group (q=2.52, P>0.05). The level of GGT of choledocholithiasis group [(424.7±317.0)U/L] was higher than those of drug-induced cholestatic liver disease group [(152.2±51.0)U/L] and PBC group [(230.5±121.0)U/L], the differences were significant (q=10.2, 8.3; P<0.05). The differences of ALP^×/GGT^× among groups were statistically significant(F=8.23, P<0.05). The level of ALP^×/GGT^× of drug-induced cholestatic liver disease group (0.95±0.54) was higher than those of PBC group (0.64±0.33)and choledocholithiasis group (0.37±0.18), and the ALP^×/GGT^× of PBC group was higher than that of choledocholithiasis group, these differences were statistically significant (q=4.2, 6.4, 5.6; P<0.05). The areas of ALP, GGT and ALP^×/GGT^× under the receiver operating characteristic (ROC) curves in the differential diagnosis between drug-induced cholestatic liver disease group(+ ) and choledocholithiasis group(-) were 0.552, 0.189, 0.972, those were 0.498, 0.298, 0.749 between PBC group (+ ) and choledocholithiasis group(-), those were 0.645, 0.319, 0.741 between drug-induced cholestatic liver disease group(+ ) and PBC group(-). The areas of ALP^×/GGT^× were the largest.The sensitivity and specificity of ALP^×/GGT^× were superior to those of ALP and GGT, which were 90.9% and 62.0%, 100.0% and 84.6%, 100.0% and 38.5%, respectively in the differential diagnosis of drug-induced cholestasis group and PBC group, drug-induced cholestasis group and choledocholithiasis group, PBC group and choledocholithiasis group.

ALP^×/GGT^× may be expected to become a new marker for differential diagnosis of cholestatic liver disease.ALP^×/GGT^× makes up for the insufficient application of serum ALP and GGT, which is important to differential diagnosis of drug-induced cholestasis, PBC and choledocholithiasis.