False-Positive hs-cTnI in a Patient on Immunotherapy: a Case of Macromolecular Interference.

IF 0.7 4区医学 Q4 MEDICAL LABORATORY TECHNOLOGY

Clinical laboratory Pub Date : 2026-09-01 DOI:10.7754/Clin.Lab.2025.251003

Bilian Luo, Qian Qiu, Jing Zhu

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引用次数: 0

Abstract

Background: High-sensitivity cardiac troponin (hs-cTn) is crucial for diagnosing acute coronary syndrome but is susceptible to analytical interference, leading to false-positive elevations (FPE). Macromolecular interferents (e.g., heterophilic antibodies or macrocomplexes) are known causes, especially in immunocompromised patients, such as those receiving immunotherapy [1,2].

Methods: A 62-year-old male with renal cell carcinoma on toripalimab presented with persistently elevated hs-cTnI levels without clinical signs of myocardial injury. Interference was assessed via polyethylene glycol (PEG) precipitation (using 25% PEG 6000), serial dilution, and alternative platform testing. PEG recovery < 20% indicated macromolecular interference.

Results: Initial hs-cTnI was 84.4 ng/mL (99th percentile URL = 24.2 ng/mL). Post-PEG, levels fell to 6.7 ng/mL (15.9% recovery), confirming interference. Serial dilution showed non-linearity. An alternate platform returned normal values. Subsequent hs-cTnI results remained normal, supporting transient interference.

Conclusions: Unexplained hs-cTnI elevations in immunotherapy-treated cancer patients should raise suspicion for macromolecular interference. PEG precipitation, dilution tests, and platform comparisons are effective verifica-tion tools. Clinician-laboratory collaboration is key to preventing misdiagnosis.

查看原文本刊更多论文

免疫治疗患者hs-cTnI假阳性：一例大分子干扰。

背景：高敏感性心肌肌钙蛋白（hs-cTn）对诊断急性冠脉综合征至关重要，但易受分析干扰，导致假阳性升高（FPE）。大分子干扰素（例如，嗜异性抗体或大复合物）是已知的原因，特别是在免疫功能低下的患者中，例如接受免疫治疗的患者[1,2]。方法：62岁男性肾细胞癌患者服用托利单抗后，hs-cTnI水平持续升高，无心肌损伤的临床症状。通过聚乙二醇（PEG）沉淀（使用25% PEG 6000）、连续稀释和替代平台测试来评估干扰。PEG回收率< 20%提示大分子干扰。结果：初始hs-cTnI为84.4 ng/mL（99百分位URL = 24.2 ng/mL）。peg后，水平降至6.7 ng/mL（恢复15.9%），证实了干扰。串联稀释呈非线性。备用平台返回正常值。随后的hs-cTnI结果保持正常，支持瞬态干扰。结论：在接受免疫治疗的癌症患者中出现不明原因的hs-cTnI升高，应引起对大分子干扰的怀疑。聚乙二醇沉淀、稀释测试和平台比较是有效的验证工具。临床-实验室合作是防止误诊的关键。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Clinical laboratory 医学-医学实验技术

CiteScore

1.50

自引率

0.00%

发文量

494

审稿时长

3 months

期刊介绍： Clinical Laboratory is an international fully peer-reviewed journal covering all aspects of laboratory medicine and transfusion medicine. In addition to transfusion medicine topics Clinical Laboratory represents submissions concerning tissue transplantation and hematopoietic, cellular and gene therapies. The journal publishes original articles, review articles, posters, short reports, case studies and letters to the editor dealing with 1) the scientific background, implementation and diagnostic significance of laboratory methods employed in hospitals, blood banks and physicians'' offices and with 2) scientific, administrative and clinical aspects of transfusion medicine and 3) in addition to transfusion medicine topics Clinical Laboratory represents submissions concerning tissue transplantation and hematopoietic, cellular and gene therapies.