Bergoglio Marina T, Sosa Gabriela A, Inchauspe María E, Andrada Marta C
Servicio de Endocrinología, Sanatorio Allende, Córdoba, Argentina. E-mail:
Servicio de Endocrinología, Sanatorio Allende, Córdoba, Argentina.
Medicina (B Aires). 2019;79(5):419-423.
We present the case of a patient who, during studies for fertility and subsequent pregnancy, showed an altered thyroid profile with elevated levels of free T4 and normal TSH. After ruling out a thyrotropic adenoma and in the absence of clinical symptoms of hyperthyroidism, the possibility of analytical interference in the immunoassays used to measure hormones was investigated. Interferences caused by heterophile antibodies, macro TSH, anti-thyroid antibodies, biotin, and to a lesser extent anti-streptavidin and anti-ruthenium antibodies have been described. The analysis of the patient was carried out in a self-analyzer whose platform uses the streptavidin-biotin system that is very susceptible to several interferents. A proposed algorithm includes a series of simple tests to perform and interpret that allow detecting or ruling out the presence of interferents. Accordingly, a comparison was made with a different analytical platform (which does not use the streptavidin-biotin system), serial dilutions, precipitation with polyethylene glycol 6000 and treatment with microparticles coated with streptavidin. Results obtained confirmed the presence of anti-streptavidin antibodies in the patient's serum. In the case of disagreements between clinical manifestations and laboratory results, the possibility of methodological interferences should be investigated in order to avoid the potential iatrogenic risk involved in an erroneous biochemical interpretation.
我们报告了一例患者，该患者在进行生育相关检查及随后的妊娠期间，甲状腺功能指标出现异常，游离T4水平升高而促甲状腺激素（TSH）正常。在排除促甲状腺素腺瘤且无甲状腺功能亢进临床症状后，对用于检测激素的免疫分析中存在分析干扰的可能性进行了调查。已描述了由嗜异性抗体、大分子TSH、抗甲状腺抗体、生物素以及程度较轻的抗链霉亲和素和抗钌抗体引起的干扰。该患者的分析是在一台自分析仪上进行的，其平台使用链霉亲和素-生物素系统，该系统极易受到多种干扰物的影响。一种提议的算法包括一系列简单的检测和解读方法，可用于检测或排除干扰物的存在。因此，将其与另一个不同的分析平台（不使用链霉亲和素-生物素系统）进行了比较，进行了系列稀释、用聚乙二醇6000沉淀以及用链霉亲和素包被的微粒处理。所得结果证实患者血清中存在抗链霉亲和素抗体。在临床表现与实验室结果不一致的情况下，应调查方法学干扰的可能性，以避免错误生化解读所涉及的潜在医源性风险。
