Novel oral chidamide and valganciclovir regimen for EBV-PTLD post-hematopoietic stem cell transplantation: A case report

Rationale: Epstein–Barr virus-related posttransplant lymphoproliferative disorder (EBV-PTLD) is a serious and potentially fatal complication following allogeneic hematopoietic stem cell transplantation (allo-HSCT). Patient concerns: We report a case of a 46-year-old male who developed EBV-PTLD 3 months after haploidentical HSCT for refractory acute myeloid leukemia. The patient presented with a persistent cough and a pulmonary nodule that increased in size from 8 mm × 5 mm to 27 mm × 25 mm over 4 weeks. Increased EBV loads were also detected (peripheral blood EBV sorting: EBV-T DNA 2.09E+03, EBV-B DNA 1.16E+03, EBV-NK DNA 7.89E+02 copies/mL; alveolar lavage fluid: 114 sequences; later rising to 3304). Diagnoses: Diagnosis was confirmed by biopsy which showed EBV-positive pleomorphic lymphoproliferative disorder with extensive necrosis. Interventions: Treatment consisted of an oral regimen of chidamide (5 mg once daily) and valganciclovir (450 mg twice daily). Outcomes: After 8 weeks of therapy, the pulmonary lesion decreased to 19 mm × 16 mm, and peripheral blood EBV-DNA levels declined significantly. Lessons: The patient achieved clinical remission with manageable side effects, including neutropenia and thrombocytopenia.