推荐使用统一ALT判断值时应重视的医学检验问题

The medical laboratory issues about recommendation on uniform cutoff values of “normal” ALT in the ACG guidelines

美国胃肠病学会(ACG)在新发布的异常肝脏生化实验评估临床指南中就丙氨酸氨基转移酶(ALT)检测结果推荐了统一"正常"范围(成年男性29~33 U/L、女性19~25 U/L),建议对结果超出该范围的"异常"者采取进一步评估干预措施。目前我国各临床医学实验室之间在ALT检测方法上仍存在一定程度的差异,无法完全确保检验方法的标准化与检测结果的一致性。ACG指南所推荐的ALT统一"正常"范围主要基于国外部分研究结论,可能并不适用于我国人群,参考上/下限亦不宜简单地等同于临床决策阈值。由于上述医学检验相关概念的应用不当,简单推荐统一ALT参考范围可能导致对受检者的过度诊断和非必要的后续检查。

In the recent American clinical guidelines dealing with laboratory tests for evaluation of liver disease,the American College of Gastroenterology(ACG)recommends ALT upper reference limits of 33 U/L for males and 25 U/L for females respectively,and that individuals with ALT above these"normal"cutoffs should be further investigated.Considering the differences between laboratory assays measuring ALT in our country,the standardization of methods and the consistency of results can not be completely ensured.The uniform"normal"range of ALT recommended by the ACG guidelines is largely based on findings from foreign studies and may not be suitable to Chinese population.On the other hand,reference upper/lower limits should not simply be equated with clinical decision thresholds.However,due to improper application of the related concepts of the above medical laboratory issues,simply recommending the uniform reference range of the ALT may lead to overdiagnosis and unnecessary follow-up examinations.