Iodinated Contrast-Induced Hypothyroidism in An Infant after Enteral Contrast Enema: A Case-Report and Systematic Review

Abstract

Excessive iodine intake may trigger the Wolff-Chaikoff effect, which results in downregulation of thyroid hormone synthesis to prevent hyperthyroidism. Failure to recover euthyroidism after the Wolff-Chaikoff effect may be seen in infants, and especially premature infants, and may result in prolonged iodine-induced hypothyroidism. We describe a rare case of a preterm infant who developed severe iodinated contrast-induced hypothyroidism after the use and prolonged stasis of enteral iodinated contrast media (ICM). In addition, a systematic literature search was performed to evaluate all available data on this condition. This systematic literature search was performed in PubMed and Embase. Studies describing the effect of enteral ICM on thyroid function were considered eligible. The primary outcome was to determine the frequency of contrast-induced hypothyroidism in infants after administration of enteral ICM. The premature infant in our center developed severe iodinated contrast-induced hypothyroidism after enteral ICM. In total, only two studies met our eligibility data, reporting eight patients. Of these eight patients, four premature infants developed contrast-induced hypothyroidism after enteral administration of ICM. Data on severity, length and frequency of contrast-induced hypothyroidism after exposure to enteral ICM is very scarce. The present case-report and literature search highlights the potential severity of this iatrogenic hypothyroidism and suggests that future studies and clinical guidelines on this specific topic would be beneficial. We recommend standardized monitoring of thyroid function after exposure to enteral ICM in newborns to prevent delayed diagnosis of severe contrast-induced hypothyroidism until evidence based recommendations can be made.