Progressive multifocal leukoencephalopathy (PML) is a rare but fatal demyelinating disease of the central nervous system, caused by the reactivation of JC virus (JCV). 1 DLd, a regimen that includes daratumumab, a human IgGκ monoclonal antibody that targets CD38, in combination with lenalidomide and dexamethasone has been approved and used for treatment of multiple myeloma (MM). 2 We report a case of a patient with MM who developed DLd-associated PML.
| C A S E REP ORTA 69-year-old man with IgG kappa MM, who received seven cycles of DLd, had a subacute and progressive clinical course of inability to manage his medicine, excretion, and dressing, eventually becoming bedridden for a month. He was diagnosed with MM (stage Ⅲ according to the international staging system for MM) and treated with carfilzomib and dexamethasone, followed by DLd for 10 months, achieving a partial response. The κ/λ free light chain ratio was reduced from 237.72 to 1.53. Diffusion-weighted magnetic resonance