A case of idiopathic multicentric Castleman disease in an alemtuzumab-treated patient with MS

Abstract

Alemtuzumab is an efficacious therapy for active relapsing-remitting MS (RRMS), but its use is complicated by the potential development of secondary autoimmunity.1 Recent data from phase 3 extension studies confirm thyroid autoimmunity as the most abundant entity of secondary autoimmunity found in up to 30%–40% of treated patients, with most events mild or moderate in severity. Data also show low rates of previously known autoimmune phenomena, such as immune thrombocytopenia and nephropathy.2 However, further entities including sarcoidosis, vitiligo, and hemophagocytic lymphohistiocytosis (HLH) have been described in real-world cohorts.3 Here, we present a case of another lymphoproliferative syndrome, namely idiopathic multicentric Castleman disease (iMCD), after alemtuzumab treatment.