Delgado Jose Antonio, Bauça Josep Miquel, Pérez Esteban Gerardo, Caimari Jaume Maria, Robles Bauza Juan
Department of Laboratory Medicine, Hospital Universitari Son Espases, Palma, Spain.
Department of Laboratory Medicine, Hospital Universitari Son Espases, Palma, Spain; Institut d'Investigació Sanitària de les Illes Balears (IdISBa), Spain.
Clin Chim Acta. 2021 Jan;512:20-25. doi: 10.1016/j.cca.2020.11.009. Epub 2020 Nov 22.
BACKGROUND-AIM: Different protocols exist for newborn screening of congenital hypothyroidism (CH) worldwide, with different thyrotropin cut-off values for repetition and confirmation tests. This study aimed to assess local protocol in terms of specificity and improve our screening process by optimizing thyrotropin cut-off values. Subsequently, the cut-off values obtained were retrospectively applied to evaluate the number of tests avoided.
Retrospective observational study between 2013 and 2019. All newborn children with a confirmation test for CH were considered for the study. ROC curve analysis was performed for thyrotropin cut-off value optimization in DBS which triggers a confirmatory test, and odds ratios were calculated. For individuals affected by the cut-off value modification, serum thyrotropin and free thyroxine in the confirmation test were analyzed for consideration of clinical outcomes.
A total of 72,133 newborn children were screened for CH, and 208 individuals were included in the study. Incidence in our population was 1:2,000 live births. The area under the ROC curve was 0.819 (CI 95%: 0.748-0.897). While the current cut-off value (thyrotropin ≥ 10mIU/L) had a specificity of 31.8% [ORs: 3.5 (CI 95%: 1.4-8.8)], the optimal cut-off value (thyrotropin ≥ 15mIU/L) yielded a specificity of 92.4% for the detection of CH and transient hypothyroidism [ORs: 15.9 (CI 95%: 7.1-35.8)], with no loss of sensitivity.
While keeping a maximum sensitivity, optimization of cut-off values may be of great use not only in management, but also in reducing family stress, which is of special relevance for the newborn.
背景-目的：全球存在不同的先天性甲状腺功能减退症（CH）新生儿筛查方案，重复检测和确认检测的促甲状腺素临界值各不相同。本研究旨在评估本地方案的特异性，并通过优化促甲状腺素临界值来改进我们的筛查流程。随后，回顾性应用所获得的临界值以评估避免的检测次数。
2013年至2019年的回顾性观察研究。本研究纳入了所有接受CH确认检测的新生儿。对干血斑中触发确认检测的促甲状腺素临界值进行ROC曲线分析，并计算比值比。对于受临界值修改影响的个体，分析确认检测中的血清促甲状腺素和游离甲状腺素以考虑临床结局。
共对72,133名新生儿进行了CH筛查，208人纳入研究。我们人群中的发病率为1:2000活产。ROC曲线下面积为0.819（95%CI：0.748 - 0.897）。当前临界值（促甲状腺素≥10mIU/L）的特异性为31.8% [比值比：3.5（95%CI：1.4 - 8.8）]，而最佳临界值（促甲状腺素≥15mIU/L）检测CH和暂时性甲状腺功能减退症的特异性为92.4% [比值比：15.9（95%CI：7.1 - 35.8）]，且不损失敏感性。
在保持最大敏感性的同时，临界值的优化不仅在管理中可能非常有用，而且在减轻家庭压力方面也很有用，这对新生儿尤为重要。
