Granulocyte transfusions: Current science and perspectives

Severe neutropenia renders patients susceptible to life-threatening bacterial and fungal infections. Despite improvements in supportive care and antimicrobial therapy, morbidity and mortality remains significant. Since the 1960s, granulocyte transfusions have been used to either treat or prevent serious infections in patients with neutropenia or neutrophil dysfunction. Despite significant optimizations in product collection, the practice of granulocyte transfusion therapy remains controversial. The use of granulocytes varies widely across institutions and countries in terms of indications, procurement, dose, infusion frequency, and duration of therapy. There are limited and conflicting data concerning its clinical effectiveness; current evidence from clinical trials does not support or refute efficacy. In this narrative review, we summarize the current evidence, discuss persistent concerns and consider future possibilities of the role of granulocyte transfusions.