Alemtuzumab-Induced Thyroid Eye Disease: A Comprehensive Case Series and Review of the Literature

Purpose: To present 5 cases of alemtuzumab-induced thyroid eye disease (AI-TED) and review the literature to highlight the natural history, severity, and outcomes as compared with conventional thyroid eye disease (TED). Methods: A multi-institutional retrospective case series of patients with AI-TED was compiled. Chart review evaluated for clinical characteristics, imaging findings, and treatment for AI-TED. Additionally, a comprehensive review of the literature identified all previously published cases of AI-TED. Results: Five new patients with AI-TED were included in this series. The average clinical activity score on presentation was 2.8 (range 1-4) and reached an average peak of 5.0 during the active phase of the disease (4-7). Patients were treated medically with selenium (40%) or monoclonal antibodies including teprotumumab or tocilizumab (40%). Surgical treatment with orbital decompression for compressive optic neuropathy was performed on 2 (40%) patients. Combined with 11 previously reported cases, these 16 patients with AI-TED had an average clinical activity score on presentation of 3.3. The average length of the AI-TED phase was 14.0 months, and all patients were treated with medical and/or surgical interventions for their disease. Conclusions: Clinical and imaging findings in AI-TED mirror that of conventional TED, however, AI-TED may present with greater severity. AI-TED may develop many months after Graves' disease; therefore, providers should be aware of this association and monitor patients for the development of severe TED.