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Severe amiodarone-induced hypothyroidism in an infant
Karen Trudel1, Shubhayan Sanatani, Constadina Panagiotopoulos
1Division of Cardiology, University of British Columbia and British Columbia Children's Hospital, Vancouver, BC, Canada.
Summary
Amiodarone treatment in infants with congenital heart defects can cause hypothyroidism. Careful thyroid function monitoring is crucial to prevent developmental issues.
Area of Science:
- Pediatric Endocrinology
- Neonatal Cardiology
- Pharmacology
Background:
- Congenital heart defects (CHDs) are common in infants.
- Arrhythmias post-cardiac surgery necessitate treatment.
- Amiodarone is used for cardiac arrhythmias but has known side effects.
Observation:
- A 7-week-old infant with a CHD developed profound hypothyroidism.
- Hypothyroidism occurred after amiodarone administration for postoperative cardiac arrhythmia.
- Levothyroxine treatment was initiated and guided by regular thyroid function tests.
Findings:
- Thyroid function normalized with levothyroxine replacement.
- Discontinuation of amiodarone allowed for cessation of thyroid hormone replacement after 6 months.
- The infant's thyroid function returned to normal after amiodarone withdrawal.
Implications:
- Infants treated with amiodarone require vigilant thyroid function monitoring.
- Untreated hypothyroidism in infancy can lead to adverse developmental outcomes.
- Early detection and management of amiodarone-induced hypothyroidism are critical in pediatric patients.
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