Thyrotoxic periodic
paralysis (TPP) is a rare complication of
hyperthyroidism, with recurrent
muscle paralysis and
hypokalemia that are caused by an intracellular shift of
potassium. TPP is relatively common in
Asian males, but is extremely rare in
children and
adolescents, even for those of
Asian descent. We describe a 16-year-old Korean
adolescent presenting with a two-week
history of episodic
leg weakness in the morning. He showed
sinus tachycardia, lower
leg weakness, and
hypokalemia.
Thyroid function test showed
hyperthyroidism, and
thyroid ultrasonography revealed a diffuse enlarged
thyroid with increased vascularity, consistent with
Graves' disease. He was treated with
beta-adrenergic blocker and
antithyroid drugs. He has been symptom free for one year, as his
hyperthyroidism has been controlled well with
antithyroid drugs. TPP should be considered in
children and
adolescents with acute
paralysis of the
lower extremities and
hypokalemia.