Impact of Granulocyte Transfusion in Patients Submitted Allogeneic Hematopoietic Progenitor Cell Transplantation – a Single Center Experience in Brazil

Background: In spite of modern antimicrobial and supportive therapy, bacterial and fungal infections are still major complications in patients with profound neutropenia. For decades, the value of granulocyte transfusion (GTX) has been explored and results are still not conclusive. Neutropenia caused by transplant conditioning regimens in patients who fail to respond to antimicrobial agents is one of the most common indications for GTX.

Objective: The purpose of this study was to analyze outcomes and risk factors for survival in patients who received GTX.

Patients and Methods: a retrospective analysis was performed on all patients submitted allogeneic hematopoietic cell transplantation (HSCT) who received GTX from january 2006 to april 2013 in our center. We analyzed patients characteristics, survival and identified risk factors for survival. Statistical analyses were performed using Graphpad Prism version 6.0. Fisher exact test was used to compare categoric variables and Kaplan-Meyer to evaluate survival. P level significance was  < 0,05.

Results: We investigate the efficacy of GTX into 32 patients with severe neutropenia and  fungal and/or bacterial infections. There were 50% (n= 16) females and 50% (n= 16) males. Of these, 46,8% (n= 15) were adults. Twenty-five percent of patients (n= 8) had genetic diseases, 43,8% (n= 14) had severe aplastic anemia and 31,2% (n= 10) had other malignant hematological diseases. A total of 196 GTX were perfomed. The average number of transfusion by patient was 6,125. The average number of granulocyte count in each bag was 3,84x10¹⁰. Every patients had neutrophil count at the hemogram below 100/mm³ and had unresponsive severe infection to antimicrobial and antifungal treatment at the day of the first GTX. In the period of infection, 56,3% (n= 18) had bacteria identified by culture: 61,1% (n= 11) gram-positive and 38,8% (n= 7) gram-negative; and 65,6% had presumed or confirmed fungal infection: 33,4% (n= 7) Fusarium sp, 38,1% (n= 8) Aspergillus sp, 9,5% (n= 2) Candida sp, 19% (n= 4) probable invasive fungal disease). Five patients received only one GTX before dying. Median survival for the whole cohort was 103 days. There was no significant difference in survival according to age, disease, number of GTX received and donor source. In bivariate analysis, patients with age higher than 14 years old and patients who received less than five transfusions had higher chance of death (p=0,015, OR-7,3 and p=0,03, OR-3,61 respectively).

 Conclusion: GTX may have an adjunctive role in severe infections in patients with profound neutropenia submitted to HSCT. Children and more than five GTX were protective factors. GTX is an underutilized supportive modality for critically ill patients undergoing allogeneic HSCT and it seems to bring benefits in some groups of patients. Prospective randomized studies are necessary to a better evaluation of this procedure.