Thyrotropin receptor antibodies predict fetal, neonatal thyroid dysfunction

WASHINGTON —Thyrotropin receptor antibody levels in pregnant women were shown to be a reliable predictor of thyroid dysfunction in fetuses and newborns, according to findings presented at the 88th Annual Meeting of the American Thyroid Association.

Maia Banige, MD , of the department of pediatrics-neonatology and pediatric emergency at the French-British Hospital Institute, Levallois-Perret, Ile-de-France, and colleagues examined data from 280,000 births between 2007 and 2014 at 10 obstetric centers of the Assistance Publique des Hopitaux de Paris. Among 2,288 women with thyroid dysfunction, 417 were found to have Graves’ disease and positive thyrotropin-receptor antibody status.

Using multiple regression analysis, researchers determined that thyrotropin receptor antibodies were the most effective means of anticipating fetal or neonatal thyroid dysfunction. Fetal thyroid dysfunction was predicted with 100% sensitivity, 64% specificity, 26% positive predictive value and 100% negative predictive value when 2.5 IU/L was used as the maternal thyrotropin receptor antibodies cutoff. For neonatal thyroid dysfunction, a cutoff of 5.9 IU/L for maternal antibodies provided 100% sensitivity, 82% specificity, 26% positive predictive value and 100% negative predictive value. A cutoff of 6.8 IU/L for newborn thyrotropin receptor antibodies provided 100% sensitivity, 94% specificity, 50% positive predictive value and 100% negative predictive value for neonatal thyroid disfunction.

The researchers noted that although risk for fetal and neonatal thyroid dysfunction is increased when a woman receives antithyroid medication during pregnancy, 65% of participants in the study did not take these drugs. They advised frequent fetal ultrasound monitoring for pregnant women with thyrotropin receptor antibodies levels of at least 2.5 IU/L and pediatric examinations for all newborns with thyrotropin receptor antibodies levels of at least 6.8 IU/L. – by Phil Neuffer

Reference:

Banige M, et al. Abstract Clinical Oral 13. Presented at: 88th Annual Meeting of the American Thyroid Association Annual Meeting; Oct. 3-7, 2018; Washington, D.C.

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