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Neonatal Thyrotoxicosis — RACP Paediatrics MCQ

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HardEndocrinologyNeonatal ThyrotoxicosisRACP Paediatrics

A 6-month-old infant is found to have a TSH of 0.01 mU/L (suppressed) and elevated free T4. His mother has Graves disease. What is causing the neonatal thyrotoxicosis?

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Correct answer: C — Neonatal Graves disease due to transplacental passage of maternal TSH receptor stimulating antibodies

Neonatal thyrotoxicosis from transplacental passage of maternal TSH receptor antibodies (TRAb) typically presents at birth or within the first 2 weeks. It is usually self-limiting (as maternal antibodies clear by 3-6 months) but can be severe. Treatment includes carbimazole and propranolol. Lugol's iodine may be needed for severe cases.

Reference: RCH Melbourne – 2024 – Clinical Practice Guidelines: Neonatal Thyrotoxicosis