Transient congenital hypothyroidism after amniofetography

Area of Science:

• Neonatal Medicine
• Endocrinology
• Radiology

Background:

• Congenital hypothyroidism is a common endocrine disorder in newborns.
• Amniofetography, a diagnostic imaging technique, involves the injection of contrast media.
• Iodine-containing contrast agents can potentially affect thyroid function.

Observation:

• A case of a newborn infant presenting with goitrous congenital hypothyroidism is detailed.
• The hypothyroidism was linked to amniofetography performed four days prior to delivery.
• A significant dose of iodine (5.22 g) was administered via water- and lipid-soluble contrast media during the procedure.

Findings:

• The infant's thyroid dysfunction was directly attributed to the iodine load from amniofetography.
• Oral L-thyroxine treatment led to a rapid disappearance of the hypothyroidism.
• Thyroid function normalized and remained stable after a 28-day withdrawal period, confirming transient hypothyroidism.

Implications:

• This case highlights the potential for iatrogenic hypothyroidism in neonates due to maternal exposure to iodinated contrast agents.
• It underscores the importance of considering maternal medical procedures when evaluating neonatal thyroid dysfunction.
• The findings support the transient nature of hypothyroidism induced by excessive iodine exposure and the efficacy of prompt L-thyroxine treatment.