PDF(Pubmed)
Abstract：
Guidelines recommend monitoring of Epstein-Barr virus (EBV) and BK virus (BKV) in solid organ and hematopoietic stem cell transplant patients. The majority of quantitative DNA testing for EBV and BKV employs unstandardized individual laboratory-developed testing solutions (LDTs), with implications for accuracy, reproducibility, and comparability between laboratories. The performance of the cobas EBV and cobas BKV assays was assessed across five laboratories, using the World Health Organization International Standards (WHO IS) for EBV and BKV, and the National Institute of Standards and Technology Quantitative Standard for BKV, and results were compared with the LDTs in use at the time. Methods were also compared using locally sourced clinical specimens. Variation was high when laboratories reported EBV or BKV DNA values using LDTs, where quantitative values were observed to differ by up to 1.5 log10 unit/mL between sites. Conversely, results from the cobas EBV and cobas BKV assays were accurate and reproducible across sites and on different testing days. Adjustment of LDTs using the international standards led to closer alignment between the assays; however, day-to-day reproducibility of LDTs remained high. In addition, BKV continued to show bias, indicating challenges with the commutability of the BKV International Standard. The cobas EBV and cobas BKV assays are automated, aligned to the WHO IS, and have the potential to reduce the variability in viral load testing introduced by differences in LDTs. Standardization of reporting values may eventually allow different centers to compare data to allow clinical decision thresholds to be established supporting improvements in patient management.IMPORTANCEThe application of center-specific cut-offs for clinical decisions and the variability of LDTs often hinder interpretation; thus, the findings reported here support the need for standardization in the field of post-transplant monitoring of EBV and BKV to improve patient management. Alongside the choice of assay, it is also important to consider which standard to use when deciding upon a testing methodology. This is a call to action for standardization, as treatment for EBV and BKV is driven by viral load test results, and the more accurate and comparable the test results are across institutions, the more informed and better the treatment decisions can be.
摘要：
指南建议在实体器官和造血干细胞移植患者中监测EB病毒（EBV）和BK病毒（BKV）。EBV和BKV的大多数定量DNA测试采用非标准化的单独实验室开发的测试解决方案（LDTs），对准确性有影响，再现性，实验室之间的可比性。在五个实验室中评估了cobasEBV和cobasBKV测定的性能，使用世界卫生组织关于EBV和BKV的国际标准(WHOIS)，和国家标准技术研究院BKV定量标准，并将结果与当时使用的LDT进行了比较。还使用当地来源的临床标本对方法进行了比较。当实验室使用LDTs报告EBV或BKVDNA值时，差异很高，其中观察到定量值在站点之间的差异高达1.5log10单位/mL。相反，cobasEBV和cobasBKV测定的结果在不同的测试日和不同的地点是准确的和可重复的。使用国际标准调整LDT导致测定之间更加一致；然而，LDTs的日常可重复性仍然很高。此外,BKV继续表现出偏见，指出BKV国际标准可交换性的挑战。cobasEBV和cobasBKV检测是自动化的，与世卫组织一致，并有可能减少由LDT差异引入的病毒载量测试的变异性。报告值的标准化可以最终允许不同的中心比较数据以允许建立临床决策阈值来支持患者管理的改进。IMPORTANCETheapplicationofcenter-specificcut-offforclinicaldecisionsandthevariabilityofLDTsoftenbainsinterpretation;thus,本文报道的研究结果支持在EBV和BKV移植后监测领域需要标准化,以改善患者管理.除了分析的选择，在确定测试方法时，考虑使用哪种标准也很重要。这是标准化行动的呼吁，因为EBV和BKV的治疗是由病毒载量测试结果驱动的，并且跨机构的测试结果越准确和可比，更明智和更好的治疗决定可以。
