グレブス病患者におけるアレムツズマブ誘発性甲状腺クリーゼの緊急甲状腺摘出術：症例報告

A 38-year-old woman with relapsing-remitting multiple sclerosis (RRMS) treated with alemtuzumab developed severe Graves' thyrotoxicosis presenting with palpitations, chest tightness, dizziness, and marked tachycardia with a heart rate of 160 per minute. Despite escalating antithyroid medications and beta-blockers, her condition progressed to thyroid storm that was resistant to medical therapy. Urgent total thyroidectomy was performed after preoperative euthyroidism was achieved with Lugol's iodine. Histopathology confirmed Graves' disease and revealed an incidental papillary thyroid carcinoma. This case is unique because it illustrates a rare instance of alemtuzumab-induced autoimmune thyroid disease progressing to treatment-refractory thyroid storm, further complicated by an incidental papillary thyroid carcinoma, an extremely uncommon coexistence. It highlights the need for heightened vigilance in monitoring alemtuzumab-treated patients for severe thyroid dysfunction and the importance of timely surgical intervention when medical therapy fails. Overall, it emphasizes that alemtuzumab-related thyrotoxicosis can evolve into a life-threatening treatment-resistant thyroid storm, and concurrent thyroid malignancy may be found incidentally, underscoring the value of multidisciplinary management and early surgical consideration.