While quantification of viruses that cause important infections in transplant recipients has been the standard of care for years, important challenges related to standardization remain. The issues are wide ranging, and until they are adequately addressed, the full impact of viral load testing regarding clinical management decisions will not be realized. This review focuses on a broad array of problems, including the lack of available FDA-approved/cleared tests, limited uptake of international standards, accurate quantification of secondary standards, specific assay characteristics, and commutability. Though some of these topics are nuanced, taken together they greatly influence the clinical utility of testing. For example, it has not been possible to define thresholds that predict the risk of developing disease and determine significant changes in serial viral load values for a given patient. Moreover, the utility of international guidelines may be limited due to the lack of a standardized assay. By summarizing the issues, the hope is that commercial companies, regulatory agencies, and professional societies can come together to advance the field and solve these problems.

中文翻译：

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移植病毒载量测试中测定间差异的持续挑战。

多年来，量化引起移植受者重要感染的病毒一直是护理的标准，但与标准化相关的重要挑战仍然存在。这些问题涉及面很广，并且在没有得到充分解决之前，将不会实现病毒载量测试对临床管理决策的全部影响。这篇综述着重于一系列问题，包括缺乏可用的FDA批准/清除的测试，对国际标准的采用有限，对次要标准的准确定量，特定的测定特性和可交换性。尽管这些主题中的一些是细微差别，但将它们放在一起会极大地影响测试的临床效用。例如，不可能定义阈值来预测患病的风险并确定给定患者的系列病毒载量值的显着变化。此外，由于缺乏标准化的检测方法，国际准则的使用可能受到限制。通过总结这些问题，希望商业公司，监管机构和专业协会能够团结起来，共同推进这一领域并解决这些问题。