Ann Pediatr Endocrinol Metab.  2014 Dec;19(4):197-201. 10.6065/apem.2014.19.4.197.

Effects of short-term potassium iodide treatment for thyrotoxicosis due to Graves disease in children and adolescents

• Jeong KU
• Lee HS
• Hwang JS

• KMID: 1769352
• DOI: http://doi.org/10.6065/apem.2014.19.4.197

Abstract

PURPOSE
Graves disease is the most common cause of hyperthyroidism in children. Inorganic iodide has been used in combination with antithyroid drugs for more effective normalization of thyroid hormones in some cases of severe thyrotoxicosis. This study aimed to investigate clinical characteristics of childhood thyrotoxicosis and effectiveness of inorganic iodide in the early phase of treatment.
METHODS
Sixty-seven pediatric patients (53 girls/14 boys, 11.1+/-3.4 years of age), with newly diagnosed thyrotoxicosis due to Graves disease were recruited. Forty-nine patients were treated with antithyroid drugs alone, while 18 patients were treated with combination of antithyroid drugs and potassium iodide. Initial thyroid function tests and levels of thyroid antibodies were recorded for all patients. Thyroid function tests were repeated 2 and 8 weeks after the initiation of treatment. Measurement thyroid antibodies were done 8 weeks after the initiation of treatment.
RESULTS
Mean triiodothyronine and free thyroxine levels were significantly lower (P<0.05) in the group receiving combined therapy of antithyroid drugs and potassium iodide after 2 weeks of treatment compared to the patients receiving antithyroid drugs alone. Eight weeks after the initiation of treatment, thyroid function tests in the two groups did not show significant differences.
CONCLUSION
The use of potassium iodide in combination with antithyroid drug is effective for more rapid normalization of thyroid hormones in the early phase treatment of childhood thyrotoxicosis, but larger studies with adequate power are needed in future.

Keyword

Thyrotoxicosis; Graves disease; Potassium iodide; Child

MeSH Terms

Adolescent*
Antibodies
Antithyroid Agents
Child*
Graves Disease*
Humans
Hyperthyroidism
Potassium Iodide*
Thyroid Function Tests
Thyroid Gland
Thyroid Hormones
Thyrotoxicosis*
Thyroxine
Triiodothyronine
Antibodies
Antithyroid Agents
Potassium Iodide
Thyroid Hormones
Thyroxine
Triiodothyronine

Figure

• 

  Fig. 1 Serial changes in serum free T4 (A), T3 (B), and TSH (C) in two groups. Open column indicates ATD alone group and shaded column indicates ATD+KI group. Significantly different at P<0.05 (*) between groups receiving ATD alone and those receiving combined therapy. T3, triiodothyronine; T4, thyroxine; TSH, thyroid-stimulating hormone; ATD, antithyroid drug; KI, potassium iodide.

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