Thyroid storm is a potentially lethal complication of
hyperthyroidism with increased
thyroid hormones and exaggerated symptoms of
thyrotoxicosis. First-line
therapy includes
methimazole (MMI) or
propylthiouracil (PTU) to block production of
thyroid hormones as a bridge toward definitive surgical treatment. Untreated
thyroid storm has a mortality rate of up to 30%; this is particularly alarming when patients cannot tolerate or fail
pharmacotherapy, especially if they cannot undergo
thyroidectomy. Therapeutic
plasma exchange (TPE) is an ASFA category III indication for
thyroid storm, meaning the optimum role of this
therapy is not established, and there are a limited number of cases in the literature. Yet TPE can remove T3 and T4 bound to
albumin,
autoantibodies,
catecholamines and
cytokines and is likely beneficial for these patients. We report a patient with
thyroid storm who could not tolerate PTU, subsequently failed
therapy with MMI, and was not appropriate for
thyroidectomy. TPE was therefore performed daily for 4 days (1.0 plasma volume with 5%
albumin replacement and 2 U of plasma). Over the treatment course, the patient's
thyroid hormones normalized and symptoms of
thyroid storm largely resolved; his T3 decreased from 2.27 to 0.81 ng/mL (normal 0.8-2.0), T4 decreased from 4.8 to 1.7 ng/mL (0.8-1.8), heart rate normalized, altered mental status improved, and he converted to normal sinus rhythm. He was ultimately discharged in euthyroid state. He experienced no side effects from his TPE procedures. TPE is a safe and effective treatment for
thyroid storm when conventional treatments are not successful or appropriate.