Challenges in screening for congenital hypothyroidism: Optimization of thyrotropin cut-off values.

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. METHODS: 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. RESULTS: 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. DISCUSSION: 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.

[Recommendations for the diagnosis and follow up of the foetus and newborn child born to mothers with autoimmune thyroid disease]. / Recomendaciones para el diagnóstico y seguimiento del feto y del recién nacido hijo de madre con patología tiroidea autoinmune.

The objective of this document is to review the current recommendations in the management of the foetus and the newborn child born to mothers with autoimmune thyroid disease. In 2017, the American Thyroid Association published guidelines for the diagnosis and management of thyroid disease during pregnancy and post-partum. In this guide, 97 recommendations were made, and an algorithm for the diagnosis and treatment of gestational hypothyroidism was proposed. Also, in this last year, a wide review was been published on the foetal and neonatal approach of the child of a mother with Graves' disease. The importance of the determination of maternal antibodies against thyrotropin receptor in the second half of pregnancy is stressed, in order to adequately stratify the risk in the neonate.