Prophylactic high-dose granulocyte transfusions following allogeneic haematopoietic stem cell transplantation.

Background and objectives: Prophylactic granulocyte transfusions (PGTxs) are controversial. Previous studies faced numerous confounders such as achieving an adequate dose. Pre-emptive or secondary PGTx for persistent, severe pre-transplant infections has rarely been reported for patients undergoing haematopoietic stem cell transplantation (HSCT). Here, we reviewed the feasibility, safety and implementation of high-dose PGTx in high-risk patients undergoing HSCT with a history of persistent, recurrent infections.

Materials and methods: We conducted a retrospective review (2018-2021) for all HSCT patients who received high-dose PGTx from donors stimulated with granulocyte colony-stimulating factor and dexamethasone at our tertiary medical centre. PGTx was carried out as secondary prophylaxis to prevent infection recurrence/progression.

Results: Seven patients received PGTx during HSCT; 95% of all transfused products contained a dose ≥0.6 × 10⁹/kg. Post-transfusion absolute neutrophil count (ANC) showed an average increase of 5.5 ± 3.7 × 10⁹/L. All PGTxs were well tolerated, with no evident transfusion reactions, adverse effects or human leukocyte antigen alloimmunization. A high overall survival rate (100% at day 30), afebrile rate (85%) and absence of infections were noted.

Conclusion: Optimized high-dose PGTx resulted in a measurable ANC increase and was well tolerated. Although efficacy and safety remain to be established, we highlight the ability to produce and implement optimized high-dose PGTx for high-risk patients undergoing HSCT.