Abstract：
We present 3 cases of discordant results from screening hemoglobin A1c (HbA1c) measured by ion-exchange high-performance liquid chromatography (HPLC) all due to various forms of interference and flagged by the instrument as \"suspected hemoglobin E (HbE).\" The first case was due to a rare hemoglobin variant, later confirmed to be hemoglobin Hoshida, the second due to \"true\" heterozygous HbE, and the third a result of analytical artifact causing splitting of the HbA1c peak without an underlying variant hemoglobin. We examine the similarities in these cases along with the laboratory work-up to classify each cause of interference to demonstrate the wide array of potential causes for the suspected HbE flag and why it warrants proper work-up. Because there is no standardized method of reporting out hemoglobin variant interference in HbA1c measurement, we discuss our laboratory\'s process of investigating discordant HbA1c measurements and reporting results in cases with variant interference as 1 possible model to follow, along with discussing the associated laboratory, ethical, and clinical considerations. We also examine the structure of hemoglobin Hoshida, HbE, and conduct a brief literature review of previous reports.
摘要：
我们介绍了3例通过离子交换高效液相色谱（HPLC）测定的血红蛋白A1c（HbA1c）筛查结果不一致的情况，所有这些都是由于各种形式的干扰，并被仪器标记为“可疑血红蛋白E（HbE）”。“第一个病例是由于一种罕见的血红蛋白变异，后来证实是血红蛋白Hoshida,第二个原因是“真正的”杂合HbE，第三个是分析伪影导致HbA1c峰分裂而没有潜在的变体血红蛋白的结果。我们检查了这些情况下的相似性以及实验室检查，以对每种干扰原因进行分类，以证明可疑HbE标志的潜在原因以及为什么需要进行适当的检查。因为在HbA1c测量中没有报告血红蛋白变异干扰的标准化方法，我们讨论了我们的实验室调查不一致的HbA1c测量和报告结果的情况下，变异干扰作为一个可能的模型遵循的过程，在讨论相关实验室的同时，伦理,和临床考虑。我们还检查了Hoshida的结构，HbE,并对以往的报道进行简要的文献综述。
