Tocilizumab in refractory pretibial myxedema: new therapeutic insights

Pretibial myxedema (PTM) is a rare extrathyroidal manifestation of Graves disease, often associated with Graves orbitopathy (GO). Tocilizumab, an interleukin-6 receptor inhibitor, is effective in refractory GO, but its role in PTM is unclear. We report the case of a 72-year-old woman with longstanding Graves disease who developed glucocorticoid-refractory GO and diffuse glucocorticoid-refractory PTM. Tocilizumab (8 mg/kg intravenously every 4 weeks) was initiated as second-line treatment of moderate to severe active GO. After 6 infusions, the patient experienced a significant improvement in both activity and severity of GO, while PTM showed near-complete resolution of edema and skin induration. No adverse events were recorded. Our findings suggest that interleukin-6 receptor inhibition with tocilizumab may represent a novel therapeutic option for refractory thyroid dermopathy, particularly in the setting of concomitant GO.