Case Report: A unique case of Philadelphia chromosome-positive mixed-phenotype acute leukemia with active Epstein-Barr virus infection in a kidney transplantation recipient.

Philadelphia chromosome-positive (Ph+) mixed-phenotype acute leukemia (MPAL) is a rare entity of acute leukemia. The co-occurrence of Ph+ MPAL and active Epstein-Barr virus (EBV) viremia in a renal transplantation recipient represents an exceptionally rare and clinically challenging scenario. Here, we report a case of Ph+ MPAL arising concurrently with EBV infection in a patient who had undergone kidney transplantation nine years earlier. A tailored therapeutic strategy was implemented, combining olverembatinib with dexamethasone, lisaftoclax and azacitidine for leukemia treatment, alongside B-cell-depleting therapy with rituximab for EBV viremia. This integrated approach successfully induced hematologic remission and achieved clearance of EBV viremia, providing a potential therapeutic framework for managing this complex dual condition. To our knowledge, this is the first reported case of this specific clinical triad, highlighting the significant therapeutic challenges posed by the coexistence of these conditions.