Method of removing incompatible red blood cells from granulocyte components

Cancer type predicts alloimmunization following RhD-incompatible RBC transfusions

BACKGROUND

Immunosuppressed, RhD-negative oncology patients tend to have lower rates of sensitization to the D antigen when they receive transfusion with RhD-positive blood components. Clinical factors associated with alloimmunization to the D antigen in RhD-negative oncology patients when they receive transfusion with RhD-positive red blood cells (RBCs) have not been well defined.

STUDY DESIGN AND METHODS

This was a 4-year, retrospective analysis identifying RhD-negative oncology patients who received RhD-positive RBCs and were not previously alloimmunized to the D antigen. Age, sex, race, ABO group, primary oncology diagnosis, and numbers of RhD-incompatible RBC transfusions were recorded. The association between antibody formation and clinical factors was studied. The incidence of alloanti-D was calculated from a subsequent antibody-detection test performed at least 28 days after receipt of the first transfusion of RhD-positive RBCs.

RESULTS

In total, 545 RhD-negative oncology patients received 4295 RhD-positive RBC transfusions. Of these, 76 (14%) became alloimmunized to the D antigen. Diagnosis type was the only factor significantly associated with responder status. The logistic regression model indicated that patients who had myelodysplastic syndrome or solid malignancies were more likely to be responders than those who had acute leukemia.

CONCLUSION

We measured a 14% sensitization rate to the D antigen in our RhD-negative oncology population. The rate of alloimmunization was higher in patients who had solid cancers (22.6%) or myelodysplastic syndrome (23%) compared with those who had other hematologic malignancies (7%). Knowledge of diagnoses that predispose to RhD alloimmunization enables better utilization of RhD-negative RBCs during times of shortage.

Granulocyte concentrates from a single high-yield apheresis can be split to support multiple patients

Allogeneic granulocyte transfusion has evolved into a viable therapeutic option for immunocompromised severely neutropenic leukemic patients and those with hematopoietic stem cell transplant with life-threatening bacterial and fungal infections. The collection of larger cell doses of granulocyte concentrates (GCs) has been facilitated by the stimulation of donors with granulocyte colony stimulating factor (G-CSF) and dexamethasone. The synergistic effect of G-CSF and dexamethasone has allowed the collection of larger cell doses of GCs and its use has increased steadily. This has allowed us to split the high-yield GC products and facilitated distribution of the split GC products to a second or third patient who needs GCs but lacks donors. The main objective of this article was to present our rationale for splitting GC products and how the split GC units were transfused to multiple patients. We believe that split GCs are as equally effective as unsplit GCs and that multiple patients benefit from splitting GCs.

Procedure for granulocyte collection performed at the Blood Centre of the Faculty Hospital Ostrava

BACKGROUND

Granulocyte apheresis is a safe and effective method for granulocyte collection. We present a five year experience (2006-2010) of the Blood Center, Faculty Hospital Ostrava, Czech Republic. Donor granulocyte transfusion is one treatment option for haemato-oncology patients with severe neutropenia complicated by bacterial/fungal infections unresponsive to standard antibiotic/antifungal treatment. In this study, we describe the experiences of the Blood Centre at the Faculty Hospital in Ostrava of granulocyte apheresis.

METHODS AND RESULTS

A total of 149 granulocyte units were collected for 33 patients from the Department of Haemato-oncology, University Hospital Olomouc, over a 5-year period (2006-2010). Information on donor selection, laboratory screening, mobilization regimen and granulocyte yield was obtained and analyzed. All mandatory screening tests for infection markers, AB0 and Rh and abnormal erythrocyte antibodies were performed. The cytomegalovirus status of the donors was not investigated. Steroids were the only mobilization regimen used, and were generally well accepted. The mean granulocyte yield was 12.6×10(9)/per transfusion unit (range 5.4-30.3). All granulocyte concentrates were irradiated and transfused according to AB0 Rh compatibility within 24 h after collection.

CONCLUSION

Based on our experience, granulocytapheresis is a safe and effective method for obtaining granulocytes but the yield can be significantly influenced by other variables. From the recipients' perspective, the use of donor granulocytes supports an effective therapeutic modality.

A prospective, randomized, double-blind study, comparing unirradiated to irradiated white blood cell transfusions in acute leukemia patients

A prospective, randomized double-blind study comparing the effects of irradiated and unirradiated white blood cells was conducted in 108 acute leukemia patients with life-threatening infections, refractory to antibiotics. The study demonstrated no significant improvement in 30-day survival or overall survival. Transfusion of unirradiated white cells did not compromise the patient's opportunity to undergo allogeneic stem cell transplant, nor the success rate or overall survival after allogeneic transplant. The important positive finding in this study was that the unirradiated white cells produced a significantly higher increment in circulating granulocytes and in a higher proportion of patients granulocyte count exceeded 1000 per microliter, approaching normal concentrations. The increase in the number and the improved survival of the unirradiated granulocytes suggest that this procedure might potentially be a method to improve the utility of granulocyte transfusions and merits further investigation. The study demonstrated non-inferiority for unirradiated white cells. There were no harmful effects such as graft-versus-host disease, indicating that such studies would be safe to conduct in the future.