RESUMEN
Cytomegalovirus (CMV) retinitis is commonly associated with immunosuppression and can cause irreversible vision loss. Chimeric antigen receptor T-cell (CAR-T) therapy has emerged as an effective cancer treatment option but requires immunosuppression, thereby increasing the possibility of acquiring opportunistic infections such as CMV. We present the case of a 76-year-old female with a history of hypertension and type 2 diabetes mellitus who initially presented with shortness of breath and was diagnosed with the activated B-cell subset of diffuse large B-cell lymphoma (DLBCL). She received multiple cycles of chemotherapy and experienced relapses with cardiac involvement. The patient developed vision loss in the right eye and was diagnosed with bilateral posterior vitritis. She underwent various treatments, including radiotherapy, systemic chemotherapy, cataract extraction, and vitrectomy. After CAR-T therapy, she developed bilateral CMV retinitis, confirmed through polymerase chain reaction testing and managed by valganciclovir. Overall, this case report describes the first reported case of bilateral CMV retinitis following CAR-T therapy for DLBCL. It emphasizes the need for early recognition and treatment of CMV retinitis to prevent permanent vision loss. The report also underscores the importance of regular ocular screening and consideration of prophylactic measures in patients undergoing CAR-T therapy.