Thyroid Storm as a Presentation of Graves Disease in a Pediatric Patient with Down Syndrome

ABSTRACT Objective: Down syndrome (DS) is associated with multiple endocrinopathies; one of the most common is thyroid dysfunction. Hashimoto thyroiditis and Graves disease have a higher prevalence in patients with DS than in the general population. For this reason, the American Academy of Pediatrics recommends annual thyroid surveillance. To highlight the importance of these recommendations we present a patient with DS who arrived at the emergency room in critical condition who was later determined to have abnormal thyroid function. Methods: We describe a child with DS who presented in severe cardiogenic shock requiring extracorporeal membrane oxygenation, later determined to be secondary to thyroid storm. She had a thyroid-stimulating hormone level of 0.01 μIU/mL (reference range is 0.6 to 4.84 μIU/mL), free thyroxine level of 4.52 ng/dL (reference range is 0.97 to 1.67 ng/dL) and free triiodothyronine level of 7.38 pg/mL (reference range is 2.53 to 5.22 pg/mL). She also had a thyroid-stimulating immunoglobulin level 270% above baseline (reference range is <140% baseline) and thyroid-stimulating hormone receptor antibody was at 47% inhibition (reference range is ≤16% inhibition). Results: We report the first case, to our knowledge, of thyroid storm in a pediatric patient with DS with no known previous thyroid disease. Conclusion: Thyroid storm should be considered in all DS patients who present with severe tachycardia that is refractory to the traditional treatment of shock. Adhering to the American Academy of Pediatrics guidelines regarding annual thyroid screening in DS patients is of a great importance. Abbreviations: AAP = American Academy of Pediatrics; DS = Down syndrome; PTU = propylthiouracil; T3 = triiodothyronine; T4 = thyroxine; TSH = thyroid-stimulating hormone