Measurement of free thyroid hormones (TH) and thyrotropin (TSH) using automated immunoassays is central to the diagnosis of thyroid dysfunction. Using illustrative cases, we describe a diagnostic approach to discordant thyroid function tests, focusing on entities causing elevated free thyroxine (FT4) and/or free triiodothyronine (FT3) measurements with non-suppressed TSH levels. Different types of analytical interference (e.g. abnormal thyroid hormone binding proteins, antibodies to iodothyronines or TSH, heterophile antibodies, biotin) or disorders (e.g. Resistance to Thyroid Hormone β or α, monocarboxylate transporter 8 or selenoprotein deficiency, TSH-secreting pituitary tumour) that can cause this biochemical pattern will be considered. We show that a structured approach, combining clinical assessment with additional laboratory investigations to exclude assay artefact, followed by genetic testing or specialised imaging, can establish a correct diagnosis, potentially preventing unnecessary investigation or inappropriate therapy.

中文翻译：

---

甲状腺激素升高且 TSH 未受抑制的患者的治疗方法。

使用自动免疫测定法测量游离甲状腺激素 (TH) 和促甲状腺素 (TSH) 对于甲状腺功能障碍的诊断至关重要。通过示例性案例，我们描述了甲状腺功能测试不一致的诊断方法，重点关注导致游离甲状腺素 (FT4) 和/或游离三碘甲状腺原氨酸 (FT3) 测量值升高且 TSH 水平不受抑制的实体。不同类型的分析干扰（例如甲状腺激素结合蛋白异常、碘甲状腺原氨酸或 TSH 抗体、嗜异性抗体、生物素）或疾病（例如甲状腺激素 β 或 α 耐药、单羧酸转运蛋白 8 或硒蛋白缺乏、TSH 分泌性垂体肿瘤）可以考虑引起这种生化模式。我们证明，一种结构化方法，将临床评估与额外的实验室研究相结合，以排除化验假象，然后进行基因检测或专门成像，可以建立正确的诊断，从而有可能防止不必要的研究或不适当的治疗。