Abstract：
BACKGROUND: IgE multiple myeloma (MM) is a rare subtype of MM that is easily misdiagnosed. We report a rare case of IgE-MM and investigate the application of the SLiM-CRAB criteria to screen for high-risk smoldering MM (SMM) patients, so as to summarize the causes and methods used to prevent missed diagnosis or misdiagnosis in IgE-MM.
METHODS: The serum monoclonal protein (M-protein) classification and IgE quantification was performed and sent to several individual institutions. The results were collected and the causes of IgE detection defects were analyzed.
RESULTS: Upon admission to our hospital, the patient\'s serum free kappa light chain was 1069.9 mg/L, free lambda light chain was 9.2 mg/L, and free kappa/lambda ratio was 115.9, which met the SLiM criteria, but without CRAB features. Immunofixation electrophoresis (IF) showed \"M-like protein aggregation bands\" in all lanes. After pretreatment with 1% β-mercaptoethanol to depolymerize the aggregation of monoclonal protein, the \"M-like protein aggregation bands disappeared. The other five institutions did not provide the correct typing results. The quantification of serum IgE was as high as 2.06 × 107 IU/mL, whereas 7 other testing institutions reported IgE levels ranging from 1.0 to 1100 IU/mL.
CONCLUSIONS: High-risk biomarkers in SLiM criteria can achieve good therapeutic effects in rare IgE-MM patients. Serum immunofixation performed without antisera against IgE, insufficient identification of the lytic bands produced by high macromolecule aggregation in IF, and the absence of a prozone effect avoidance procedure during IgE quantitative detection are the primary causes of missed diagnosis or misdiagnosis in patients with IgE-MM.
METHODS: The serum monoclonal protein (M-protein) classification and IgE quantification was performed and sent to several individual institutions. The results were collected and the causes of IgE detection defects were analyzed.
RESULTS: Upon admission to our hospital, the patient\'s serum free kappa light chain was 1069.9 mg/L, free lambda light chain was 9.2 mg/L, and free kappa/lambda ratio was 115.9, which met the SLiM criteria, but without CRAB features. Immunofixation electrophoresis (IF) showed \"M-like protein aggregation bands\" in all lanes. After pretreatment with 1% β-mercaptoethanol to depolymerize the aggregation of monoclonal protein, the \"M-like protein aggregation bands disappeared. The other five institutions did not provide the correct typing results. The quantification of serum IgE was as high as 2.06 × 107 IU/mL, whereas 7 other testing institutions reported IgE levels ranging from 1.0 to 1100 IU/mL.
CONCLUSIONS: High-risk biomarkers in SLiM criteria can achieve good therapeutic effects in rare IgE-MM patients. Serum immunofixation performed without antisera against IgE, insufficient identification of the lytic bands produced by high macromolecule aggregation in IF, and the absence of a prozone effect avoidance procedure during IgE quantitative detection are the primary causes of missed diagnosis or misdiagnosis in patients with IgE-MM.
摘要：
背景：IgE多发性骨髓瘤（MM）是一种罕见的MM亚型，容易误诊。我们报告了罕见的IgE-MM病例，并研究了SLiM-CRAB标准在筛查高危闷烧MM（SMM）患者中的应用，总结IgE-MM漏诊或误诊的原因及预防方法。
方法：进行血清单克隆蛋白（M-protein）分类和IgE定量，并发送给几个单独的机构。收集结果并分析IgE检测缺陷的原因。
结果：入院后，患者血清游离κ轻链为1069.9mg/L，游离λ轻链为9.2mg/L，游离κ/λ比为115.9，符合SLiM标准，但没有CRAB功能。免疫固定电泳（IF）在所有泳道中均显示“M样蛋白聚集带”。用1%β-巯基乙醇预处理后解聚单克隆蛋白的聚集，“M样蛋白聚集带消失了。其他五个机构没有提供正确的打字结果。血清IgE的定量高达2.06×107IU/mL，而其他7家检测机构报告的IgE水平范围为1.0至1100IU/mL.
结论：SLiM标准中的高危生物标志物可以在罕见IgE-MM患者中取得良好的治疗效果。不使用抗IgE抗血清进行血清免疫固定，对IF中高分子聚集产生的裂解带的识别不足，IgE定量检测过程中缺乏前区效应回避程序是IgE-MM患者漏诊或误诊的主要原因。
方法：进行血清单克隆蛋白（M-protein）分类和IgE定量，并发送给几个单独的机构。收集结果并分析IgE检测缺陷的原因。
结果：入院后，患者血清游离κ轻链为1069.9mg/L，游离λ轻链为9.2mg/L，游离κ/λ比为115.9，符合SLiM标准，但没有CRAB功能。免疫固定电泳（IF）在所有泳道中均显示“M样蛋白聚集带”。用1%β-巯基乙醇预处理后解聚单克隆蛋白的聚集，“M样蛋白聚集带消失了。其他五个机构没有提供正确的打字结果。血清IgE的定量高达2.06×107IU/mL，而其他7家检测机构报告的IgE水平范围为1.0至1100IU/mL.
结论：SLiM标准中的高危生物标志物可以在罕见IgE-MM患者中取得良好的治疗效果。不使用抗IgE抗血清进行血清免疫固定，对IF中高分子聚集产生的裂解带的识别不足，IgE定量检测过程中缺乏前区效应回避程序是IgE-MM患者漏诊或误诊的主要原因。
