Graves Disease in Infancy

Background: Graves disease (GD) is the most common cause of hyperthyroidism worldwide. The usual age of presentation is between 20-30 years, and it is more common in females. Transient hyperthyroidism does occur in infants born to mothers with GD, however, the novo GD in infants is extremely rare. We are aware of only four cases of GD in children under the age of 2 years old previously reported in the literature, with the youngest being of 18 months. Although rare, the complications can be devastating, so identifying and treating GD in infants is vital. We describe an infant who presented at 12 months of life with poor weight gain. Patient Findings: A 12-month old female patient presented with weight loss, tachycardia, diaphoresis and hypertension. She had a palpable thyroid gland without ocular changes. She was found to have an undetectable Thyroid Stimulating Hormone (TSH) with an elevated free T4 of 2.1 ng/dL (normal 0.80 - 1.50 ng/dL). She was stabilized in the intensive care unit with beta-blocker and methimazole. The diagnosis of GD was subsequently confirmed with an extremely elevated elevated Thyroid Stimulating Immunoglobulins (TSI) titer of 263 Iu/L (normal 0.00-0.55 IU/L), her TSH receptor gene was normal. At 34 months of age, her TSI titer is still elevated at 34 IU/L and she still requires methimazole to maintain a euthyroid state. She is growing and developing appropriately. Conclusion: To our knowledge, this report describes the youngest child to be diagnosed with GD in the English literature. Only four patients between the ages of 18 - 24 months have been described. Autoimmune diseases are rare in infants, the reason for which GD developed at such a young age remains unclear. Clinical signs and symptoms of hyperthyroidism in infants can be subtle and easily missed: increased growth velocity, failure to gain weight, autonomic changes, and irritability. Most patients have an enlarged thyroid gland, and some have ocular changes. The major long-term complications of undiagnosed hyperthyroidism include craniosynostosis and permanent neurocognitive damage. A high index of suspicion is needed for the recognition and prompt treatment of GD in infants, leading to better clinical outcome.