Thyroid Storm With Coma in a Patient with Metastatic Thyroid Carcinoma and Graves Disease: Won the Battle but Lost the War

Objective: To describe the background and events that may precipitate thyroid storm (TS) with coma as well as the course of treatment intervention and our patient's response to treatment. Methods: We present a case of TS with coma including precipitants, thyroid function tests, thyroid ultrasound, computed tomography findings, course, treatment, and outcome. Results: A 71-year-old woman was hospitalized with back pain and right leg weakness due to a newly diagnosed, 12.4-cm sacral tumor. The tumor had metastasized from poorly differentiated papillary thyroid carcinoma. The patient developed TS characterized by thyrotoxicosis with fever, tachycardia, and mental status change progressing to coma over several days. Treatment including antithyroid drugs, steroids, saturated solution of potassium iodide, L-carnitine, therapeutic plasma exchange, and thyroidectomy reversed the prolonged coma and TS, but left residual flaccid quadriplegia. The patient eventually died. Conclusion: This patient presented with multiple rare causes of TS (computed tomography contrast and Graves disease in the setting of high-volume thyroid cancer) and a rare manifestation of TS (coma). The TS included fever, tachycardia, and rapid onset of prolonged coma in the setting of thyrotoxicosis. Precipitants of the TS may have included enlarged thyroid tissue from goiter, distant metastasis, the operation, computed tomography contrast exposure, and high levels of thyroid-stimulating immunoglobulin. Multifaceted treatments, most importantly therapeutic plasma exchange, resolved the coma and TS, but the patient still succumbed to comorbidity. We agree with the Japan Thyroid Association recommendation for therapeutic plasma exchange in patients with TS, especially those in a coma who do not awaken within 24 to 48 hours of starting conventional TS treatment.