Acute thyroid hormone exposure in children: A national retrospective study using health data routinely collected by the French Poison Control Centers

Abstract

Abstract Purpose: Thyroid hormones are involved in many metabolic and physiological processes, including basal metabolism, thermoregulation, and heart rate. However, there is little information on acute exposure in children, with only a few cases reports or small cases series being available. Our study was undertaken to provide more information about the epidemiological and clinical course of l-thyroxine poisoning in a large pediatric population. Study design: This multicenter historical cohort study was conducted using data from the French Poison Control Centers on the acute ingestion of thyroid hormone in children (0–12 years of age) between 1 January 2018 and 31 December 2020. Results: Of the 2,321 files analyzed, 1,248 cases were included. Preschool children aged 2–5 years old accounted for 79.4% of the cases. Oral ingestion was unintentional in 98% of the cases. The medicine was from a relative in 97.5% of cases. Only 10 (0.8%) children were symptomatic. No symptoms were reported below a dose of 6.6 µg/kg and some patients remained asymptomatic up to an assumed dose of 500 µg/kg. The symptoms reported were minor, transitory, and limited to tremor, agitation, diarrhea, vomiting, and tachycardia. Comparing the assumed intake doses between unintentional and intentional exposure, and between asymptomatic and symptomatic cases, there were no significant differences (p > 0.05). Conclusion: Acute l-thyroxine poisoning in children was mainly accidental (unintentional) and has only a few benign symptoms. The clinical outcome is good even if the assumed ingested dose is massive (up to 500 µg/kg).