ABSTRACT Background Kaposi sarcoma herpes virus (KSHV) is associated with multiple clinical manifestations, including primary effusion lymphoma, an aggressive CD38+ B cell lymphoma with a plasmablastic phenotype. Case This case describes an antiretroviral therapy‐adherent person with HIV who presented with concurrent KSHV‐related disorders of Kaposi sarcoma (KS), multicentric Castleman disease (MCD), and extracavitary primary effusion lymphoma (EC‐PEL). Single‐cell RNAseq (scRNAseq) and multiplex immunohistochemistry (mIHC) provide detailed insights into differences in cellular composition and viral and cellular transcriptomic differences between these diseases. Moreover, the case describes a long‐term remission with single‐agent anti‐CD38 antibody, daratumumab, in a chemotherapy‐refractory case. Conclusion This case highlights the differing clinical manifestations of KSHV and the efficacy of immunotherapy in KSHV‐associated primary effusion lymphoma.
Roberts et al. (Mon,) studied this question.