Kyoko Masuda, Mana Sota, Aika Kitamura, Tsutomu Yoshida, Tomohiko Tanigawa, Kaito Takikawa, Kiho Tozuka, Miki Sakamoto, Takahide Shindo, Takayuki Fujii, Kentaro Yamaguchi, Yuriko Nakamura, Ryo Inaba, Kei Ishizuchi, Hiromichi Matsushita, Rie Yamazaki, Yuya Koda, Masatoshi Sakurai, Keisuke Kataoka
Human herpesvirus 6 (HHV-6) encephalitis after chimeric antigen receptor (CAR) T-cell therapy is rare and it usually occurs early after infusion. We report a case of a 76-year-old man with diffuse large B-cell lymphoma who developed late-onset HHV-6 encephalitis with secondary hemophagocytic lymphohistiocytosis (HLH) 14 months after the infusion of lisocabtagene maraleucel. A cerebrospinal fluid (CSF) analysis revealed elevated HHV-6B DNA levels, and hemophagocytosis was identified in both the bone marrow and CSF. Despite ganciclovir and HLH-directed therapy, the patient died of a bacterial infection. HHV-6-associated disease should be considered even long after CAR T-cell therapy in patients with persistent fever, hyperinflammation, cytopenia, or neurological symptoms.