Alemtuzumab-induced halo nevus-like hypopigmentation – New insights into secondary skin autoimmunity in response to an immune cell-depleting antibody

We describe a 33‐year‐old male patient who developed hypopigmentation around his melanocytic nevi with disappearance of the nevi in August 2018. In June 2016 he had been diagnosed with highly active RRMS and treated with alemtuzumab in September 2016 for the first time. In September 2017 another cycle of alemtuzumab was administered. The patient’s family history for vitiligo was unremarkable and he had no autoimmune thyroid disease.