Effect of iodinated contrast medium on thyroid function: a study in children undergoing cardiac computed tomography.

BACKGROUND

Few studies, and with conflicting results, have evaluated the potential effects of iodinated contrast media on children's thyroid function.

OBJECTIVE

To investigate the effects of iodinated contrast medium on thyroid function in neonates, infants and young children with congenital heart disease undergoing cardiac computed tomography (CT).

MATERIALS AND

METHODS

We retrospectively evaluated 10 neonates (group 1) and 23 infants and young children (group 2) without thyroid or renal disease for serum levels of thyroid-stimulating hormone, free triiodothyronine and free thyroxine before contrast-enhanced cardiac CT, 48 h after CT and at discharge from the hospital. Cardiac CT was performed with intravenous administration of 1.14±0.17 mL/kg of body weight of iopromide (containing 370 mg of iodine/mL).

RESULTS

Group 1 had a reduction of thyroid-stimulating hormone from baseline to 48 h post injection (P=0.002). Group 2 had a reduction of thyroid-stimulating hormone median levels from baseline to 48 h post injection and an increase from 48 h to discharge (P=0.0005 and P=0.0001, respectively).

CONCLUSION

Intravenous iodinated contrast medium in children with congenital heart disease caused transient thyroid-stimulating hormone decrease 48 h after CT, with thyroid-stimulating hormone returning to normal range at discharge.