Refractory Thyroid Storm Due to Graves Disease in a Patient With Thymic Lymphoepithelial Carcinoma

Thyroid storm is a life-threatening endocrine emergency that warrants early clinical recognition and aggressive intervention. We present a 64-year-old female with no known history of thyroid disease, who presented to her primary care physician with dyspnea on exertion and was found to have an anterior mediastinal mass. She had elective thymectomy. Pathology confirmed thymic lymphoepithelial carcinoma. Postoperatively, she developed altered mental status, fever, and atrial fibrillation with marked elevation of thyroid hormones, consistent with thyroid storm. She decompensated rapidly and was treated aggressively with standard therapies for thyroid storm, including beta-blockers, methimazole, cholestyramine, steroids, and iodine, with poor response. The patient eventually underwent 4 sessions of therapeutic plasma exchange (TPE) with marked improvement in her symptoms. This case reports a possible association between thymic lymphoepithelial carcinoma and Graves disease and highlights the utility of TPE in cases of severe thyroid storm that are refractory to traditional treatments. We learn from this case that evaluating thyroid function tests in patients with thymic or mediastinal masses before surgery might be helpful. TPE should be considered in patients with thyroid storm refractory to traditional therapies.