Abstract：
BACKGROUND: As one of the most requested profiles of blood tests, there is a need for standardization among liver function tests (LFT). Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) are key markers of hepatocellular injury. ALT and AST are used to calculate a Fibrosis-4 (FIB-4) score for assessing liver fibrosis. Despite recommendations by the International Federation of Clinical Chemistry (IFCC) to include pyridoxal-5-phosphate in ALT and AST assay methodologies, most laboratories continue to omit this.
METHODS: Data from the UK NEQAS for Clinical Chemistry Scheme, Distribution 1160 (November 2023), was reviewed to investigate variation in practice regarding liver blood tests in relation to ALT, AST and FIB-4. In addition, a series of questions audited laboratory practice in relation to liver enzymes.
RESULTS: Wide variation was seen in LFT profiles offered by laboratories, with 32 different combinations of tests used. The IFCC-recommended methods for ALT and AST are used by one-third of laboratories and give significantly higher results than non-IFCC methods. Laboratories using IFCC methods also reported significantly higher FIB-4 scores. Reference ranges and cut-offs for these tests also varied, and did not account for method-related differences in results.
CONCLUSIONS: The lack of standardization of LFTs can have a significant impact on patient care. The difference in results for ALT, AST and FIB-4 in laboratories not using IFCC-recommended methods may lead to misdiagnosis. This issue should be addressed by laboratories using methods including pyridoxal-5-phosphate. Until then, method-related reference ranges and cut-offs for ALT, AST and FIB-4 are required.
METHODS: Data from the UK NEQAS for Clinical Chemistry Scheme, Distribution 1160 (November 2023), was reviewed to investigate variation in practice regarding liver blood tests in relation to ALT, AST and FIB-4. In addition, a series of questions audited laboratory practice in relation to liver enzymes.
RESULTS: Wide variation was seen in LFT profiles offered by laboratories, with 32 different combinations of tests used. The IFCC-recommended methods for ALT and AST are used by one-third of laboratories and give significantly higher results than non-IFCC methods. Laboratories using IFCC methods also reported significantly higher FIB-4 scores. Reference ranges and cut-offs for these tests also varied, and did not account for method-related differences in results.
CONCLUSIONS: The lack of standardization of LFTs can have a significant impact on patient care. The difference in results for ALT, AST and FIB-4 in laboratories not using IFCC-recommended methods may lead to misdiagnosis. This issue should be addressed by laboratories using methods including pyridoxal-5-phosphate. Until then, method-related reference ranges and cut-offs for ALT, AST and FIB-4 are required.
摘要：
背景作为血液检查中最需要的配置文件之一，肝功能检查（LFT）之间需要标准化。丙氨酸氨基转移酶(ALT)和天冬氨酸氨基转移酶(AST)是肝细胞损伤的关键标志物。ALT和AST用于计算纤维化-4(FIB-4)评分以评估肝纤维化。尽管国际临床化学联合会（IFCC）建议在ALT和AST测定方法中包括吡哆醛-5-磷酸，大多数实验室继续忽略这一点。方法数据来自英国NEQAS临床化学计划，分布1160（2023年11月），进行了审查，以调查实践中关于肝脏血液测试与ALT有关的变化，AST和FIB-4。此外,与肝酶有关的一系列问题审核了实验室实践。结果在实验室提供的LFT剖面中发现了很大的变化，使用32种不同的测试组合。三分之一的实验室使用IFCC推荐的ALT和AST方法，并给出比非IFCC方法明显更高的结果。使用IFCC方法的实验室也报告了显著更高的FIB-4得分。这些测试的参考范围和截止值也有所不同，并且没有考虑结果中与方法相关的差异。结论LFTs缺乏标准化可能会对患者护理产生重大影响。ALT的结果差异，不使用IFCC推荐方法的实验室AST和FIB-4可能导致误诊。这个问题应该由实验室使用包括吡哆醛-5-磷酸的方法来解决。在那之前,与方法相关的ALT参考范围和截止值，需要AST和FIB-4。
