The impact of donor type and ABO incompatibility on transfusion requirements after nonmyeloablative haematopoietic cell transplantation

Blood components utilization in hematopoietic stem cell transplantation: Thirteen-year analysis from an apex oncology center of India

BACKGROUND

Hematopoietic stem cell transplantation (HSCT) is a potentially curative treatment modality for a range of hematological disorders including malignancies. The increasing volumes of HSCTs impact transfusion services and the requirement of blood products vary depending on the primary disease, type and phase of transplant, and the HSCT donor type.

MATERIALS AND METHODS

This study analyzed the factors affecting blood component requirements in patients undergoing HSCT. The authors studied the transfusion requirement of packed red blood cells (PRBC) and platelets (PLT) up to 100 days post-transplant among 617 adult patients undergoing HSCT during the study period (2007-2019).

RESULTS

Requirement of PRBC and PLT was significantly higher (P < 0.05) in allogenic HSCT cases across all three phases of transplant compared to autologous HSCT. Unlike PRBC requirement, the PLT requirement was significantly higher during peri-transplant period for haploidentical HSCT and major ABO-incompatible HSCT group compared to matched related donor HSCT and ABO identical HSCT, respectively. In subset analysis based on diagnosis with leukemia as reference, the multiple myeloma group required less while the anemia group required more PRBC and PLT transfusions. The leukemia group required more PRBC than lymphoma group, while the PLT requirement was vice-versa.

CONCLUSION

Factors such as allogeneic HSCT, haploidentical donor type, major ABO-incompatible HSCT, and primary diagnosis as leukemia or anemia were the predictors for increased need of blood products. As higher transfusion requirements may translate into increased costs of treatment, a study like this can help in managing blood component inventory and planning treatment costs of a HSCT program.

Transfusion Burden in Allogeneic Hematopoietic Stem Cell Transplantation over Time: Experience from a Single Institution

INTRODUCTION

Transfusion plays a main role in supportive treatment for patients who receive an allogeneic hematopoietic stem cell transplantation (HSCT). In this study, we compare the transfusion requirements of patients undergoing different modalities of HSCT according to different time periods. The objective is to assess the evolution of HSCT transfusion requirements over time, from a single institution.

METHODS

The clinical charts and transfusion records of patients who underwent HSCT of different modalities at La Fe University Hospital during a twelve-year period were reviewed (2009-2020). For analysis, we divided the overall time into three periods: 1 from 2009 to 2012, 2 from 2013 to 2016 and 3 from 2017 to 2020. The study included 855 consecutive adult HSCT: 358 HLA-matched related donors (MRD), 134 HLA-matched unrelated donors (MUD), 223 umbilical cord blood transplantation (UCBT) and 140 haploidentical transplants (Haplo-HSCT).

RESULTS

There were no significant differences in RBC and PLT requirements or transfusion independence among the three time periods for MUD and Haplo-HSCT. However, the transfusion burden increased significantly for MRD HSCT during the 2017-2020 period.

CONCLUSION

despite HSCT modalities having evolved and changed over time, overall transfusion requirements have not significantly decreased and continue to be a cornerstone of transplantation-supportive care.

Impact of Donor-to-Recipient ABO Mismatch on Outcomes of Antithymocyte Globulin-Based Peripheral Blood Stem Cell-Derived Myeloablative Conditioning Haploidentical Stem Cell Transplantation

ABO incompatibility is common in hematopoietic stem cell transplantation (HSCT); however, the impact of donor-recipient ABO compatibility on transplantation outcomes in different HSCT settings is controversial. Moreover, haploidentical stem cell transplantation (haplo-SCT) with peripheral blood stem cell (PBSC)-derived grafts has not been well investigated. The present study aimed to investigate the impact of ABO incompatibility on post-transplantation outcomes, engraftment kinetics, blood product requirements, transfusion independence, and the incidence of poor graft function (PGF) in antithymocyte globulin (ATG)-based haplo-SCT with PBSC grafts during long-term follow-up. We prospectively evaluated 510 patients with hematologic malignancies who underwent haplo-SCT after myeloablative conditioning (MAC). The primary endpoint was overall survival (OS), and secondary endpoints were nonrelapse mortality (NRM), graft-versus-host disease (GVHD), relapse, neutrophil and platelet engraftment, blood transfusion requirements, transfusion independence, and the incidence of PGF. There was no significant association between ABO matching and OS, disease-free survival (DFS), relapse, NRM, grade II-IV acute GVHD, grade III-IV acute GVHD, and moderate and severe chronic GVHD. There were also no significant differences in neutrophil and platelet engraftment, blood transfusion independence, and transfusion requirements at 30, 60, 90, 180, and 365 days post-transplantation among patients with ABO matching and those with minor, major, or bidirectional ABO incompatibility. Donor-recipient ABO matching did not differ significantly according to graft function (good versus poor). ABO incompatibility status has no major impact on patient outcomes in patients with hematologic malignancies undergoing ATG-based MAC haplo-SCT with PBSC-derived grafts.

Investigation of risk factors associated with erythrocyte engraftment after ABO-incompatible hematopoietic stem cell transplantation

ABO-incompatible hematopoietic stem cell transplantations (HSCTs) are widely practiced; however, the delay in erythrocyte engraftment can be problematic. While erythrocyte engraftment is usually indicated by an increase in reticulocyte levels without the need for erythrocyte transfusions, the disappearance of recipient-derived anti-A/B isoagglutinin and detection of donor-derived A/B antigens can also be used as other parameters. We conducted a retrospective analysis of 68 ABO-incompatible HSCTs, focusing on major and bidirectional mismatch. We analyzed known clinical risk factors associated with delayed erythrocyte engraftment using the three parameters (disappearance of anti-A/B isoagglutinin in recipient, detection of donor-derived A/B antigen, and reticulocyte levels >1%). Although the three parameters were well correlated, the results showed heterogeneity when analyzing the associated risk factors for delayed erythrocyte engraftment. In the analysis of all cases, the requirement for an HLA-matched platelet transfusion was a common risk factor. Furthermore, erythrocyte engraftment was slower in adults than in children. In adults, cytomegalovirus antigenemia was a risk factor for two parameters; however, in children, underlying disease was a common risk factor for all parameters. There is a complex relationship between erythrocyte engraftment and various factors related to HSCTs. Our results suggest that greater accuracy is possible by using analysis methods other than the measurement of reticulocyte levels.

Increased blood transfusion after outpatient autologous transplantation with reduced intensity conditioning for hematological malignancies predicts worse outcomes

Transfusion has a recognized immunomodulatory effect, and its role on the outcomes after an ambulatory autologous hematopoietic stem cell transplantation (auto-HSCT) following reduced intensity conditioning (RIC) has not been documented. A study to assess factors associated with the number of packed red blood cells (PRBCs) and platelet units transfused and their impact on survival rates of auto-HSCT recipients after RIC was conducted between 2013 and 2019. Transfusions were recorded from days 0 to 100. Of the 130 patients studied, seventy (53.9%) required transfusion support. The median number of PRBC transfused was 2 (range 1-20), and for platelets, it was also 2 units (range 1-19). Infused CD34 + cells/kg, pre-transplant CMV status, and relapse/progression were significantly associated with the number of PRBC units transfused and sex, infused CD34 + cells/kg, and pre-transplant CMV status with the number of platelet units transfused. In multivariate analysis, a high/very high Disease Risk Index (P = .001) (P = .001) and transfusion of ≥ 5 total blood products (P = .001) (P = .010) were associated with decreased disease-free and overall survival. Two-year cumulative incidence of relapse was 50% for transfused patients vs. 34% for those not transfused (P = .009). These data suggest that the transfusion burden and its interplay with other patient and transplant-related factors could be associated with inferior auto-HSCT outcomes.

A high transfusion burden following an ambulatory-allogeneic hematopoietic cell transplantation using reduced-intensity conditioning is associated with adverse outcomes

OBJECTIVES

Ambulatory allogeneic hematopoietic cell transplantation (allo-HCT) after reduced-intensity conditioning (RIC) is a cost-effective option for hematology patients. Data on the impact of transfusion burden in this setting are scarce; we analyzed this retrospectively.

METHODS

A study of 177 HLA-identical and haploidentical allo-HCT recipients on an outpatient basis was conducted between 2013 and 2019. Packed red blood cell (PRBC) and platelet transfusions were documented from days 0-100 after HCT.

RESULTS

A total of 121 patients (68.4%) required transfusion while 56 (31.6%) did not. In the multivariate analysis, a lower disease-free (DFS) and overall survival (OS) were documented for patients that received ≥9 total blood products (p = 0.018) (p = 0.014), those who required hospitalization (p = 0.001) (p < 0.001), had acute graft-versus-host disease (p = 0.016) (p = 0.004), and a high/very high Disease-Risk-Index (p = 0.002; p = 0.004), respectively. Transfusion of ≥5 PRBC units was associated with a lower OS (p = 0.027). The cumulative incidence of transplant-related mortality at two years for an HLA-identical transplant was 9.5% and for haploidentical, it was 27.1% (p = 0.027); this last group had significantly more transfusion demands than HLA-identical recipients (p = 0.029).

CONCLUSION

Increased blood product utilization is an independent predictor of decreased survival in ambulatory RIC allo-HCT recipients. Further evidence leading to individualized guidelines to transfuse in this complex scenario is needed.

Effect of donor type on volume of blood transfusions required after allogeneic hematopoietic cell transplantation

We reviewed blood product use in 729 consecutive allogeneic hematopoietic cell transplantation (allo-HCT) recipients at our center to assess the volume of red blood cells (RBCs) and platelets required after allo-HCT. The median number of bags required by day 30 was 4 for RBCs (range 0-22) and 9.5 for platelets (0-53). Multivariate analysis showed that related peripheral blood stem cell transplantation (PBSCT) required a significantly lower RBC transfusion volume by day 30 compared to unrelated bone marrow transplantation (UBMT). PBSCT from haplo-identical related donors and cord blood transplantation (CBT) required a significantly greater RBC transfusion volume. For platelet transfusion, related and unrelated PBSCT required a significantly lower volume than UBMT, and CBT a greater volume. Other factors independently associated with greater RBC transfusion volume were male sex, disease status other than complete remission, and major ABO mismatch. For platelet transfusion, these were male sex, disease status, and HCT-specific comorbidity index of 1. Although the burden of blood transfusions may not be the most important factor when choosing a donor type, our findings may provide a foundation for nationwide strategies to prepare blood products and inform aspects of national healthcare expenditures.

Red blood cell and platelet transfusion support in the first 30 and 100 days after allogeneic hematopoietic cell transplant

BACKGROUND

Allogeneic hematopoietic stem cell transplant (allo-HSCT) recipients often require substantial but variable transfusion support.

STUDY DESIGN AND METHODS

This single-center, retrospective study evaluated the red blood cell (RBC) and platelet (PLT) transfusion data of first-time allo-HSCT recipients transplanted in 2011 to 2017. Multivariate analyses were performed to assess the associations between patient and transplant-related factors and transfusion requirements.

RESULTS

The study included 1762 patients who received peripheral blood stem cells (88.2%), marrow (7.0%), or umbilical cord (4.8%) from matched related (38.3%), unrelated (49.2%), or haploidentical (7.8%) donors. Almost all patients required RBCs (88.3%) or PLTs (97.4%) during the first 30 days, with medians of 3 (range, 1-37) RBC and 6 (range, 1-144) PLT units transfused. Fewer patients required RBC (43.8%) or PLT (27.3%) transfusions during Days 31 to 100, but the median (range) numbers of RBC and PLT units remained high at 3 (1-36) and 6 (1-116) among transfused patients. RBC and PLT transfusion independence was reached in medians of 24 (95% confidence interval [CI], 22-26) and 12 (95% CI, 11-12) days, respectively. Haploidentical donor, cord graft, and requiring RBC transfusions in the 10 days before HSCT were the most significant independent factors predictive of increased transfusion requirements. Advanced disease, diagnosis, ABO incompatibility, conditioning intensity, CD34+ cell dose, presence of severe acute graft-vs-host disease, and changes in recommended transfusion triggers were also shown to independently impact transfusion requirements.

CONCLUSIONS

This study provided for the first time quantitative and comparative transfusion data on a large contemporary cohort of HSCT recipients, including haploidentical and cord graft recipients, and identified factors predictive of increased transfusions.

Poor graft function after T cell-depleted allogeneic hematopoietic stem cell transplant

PGF implies persistent cytopenia in the presence of predominant donor chimerism. We examined contributors to PGF in 104 HCT recipients who survived ≥100 days without relapse or major complications. Surrogate parameters for PGF were: Hg <10 g/dl, RBC transfusion dependence, platelet count <20 × 10⁹/L or ANC < 0.5 × 10⁹/L. All patients received T cell depletion with alemtuzumab or ATG. The 2-year OS and PFS probabilities were 66%, 95%CI (56 - 75%) and 51%, 95%CI (41-60%) respectively. Fifty-four patients (52%) met one or more PGF criteria. There was significant association between major ABO incompatibility and platelet <20 × 109/L (OR = 4.7, 95%CI 1.05-21.26, p = .043), acute GVHD and Hg <10 g/dl (OR 3.7, 95%CI 1.4-9.6, p = .005) and CMV viremia and ANC < 0.5 × 10⁹/L (OR 3.0, 95% CI 1.0, 8.7, p = .043). NRM was significantly higher in the PGF group compared to patients with adequate graft function (45.5% vs 16.7%, p = .014).

Transfusion support for matched sibling allogeneic hematopoietic stem cell transplantation (1993-2010): factors that predict intensity and time to transfusion independence

BACKGROUND

Patients undergoing allogeneic hematopoietic stem cell transplant require variable, often extensive transfusion support. Identification of factors that predict urgent, intensive, or special needs should improve management of these patients.

STUDY DESIGN AND METHODS

This is a retrospective study of red blood cell (RBC) and platelet transfusion support provided for sequential matched sibling donor allogeneic transplants conducted at the Clinical Center, National Institutes of Health, from 1993 through 2010. Factors potentially important for predicting quantity of RBC and platelet transfusions, and time to transfusion independence through Day 200 following hematopoietic stem cell transplantation were evaluated.

RESULTS

Subjects (n = 800) received 10,591 RBC and 10,199 platelet transfusions. Multivariable analysis demonstrated that the need for RBC pretransplant, CD34+ dose, transplant year, diagnostic category, and ABO match were significantly independently associated with quantity of RBC transfusions during Days 0 through 30. Only pretransplant need for RBCs, CD34+ dose, and transplant year had significance during Days 0 through 100. Similar analyses for quantity of platelet transfusions demonstrated that for both Days 0 through 30 and 0 through 100 significant factors were need for platelet support before transplant, CD34+ dose, transplant year, and transplant regimen. Of note, long term, during Days 101 through 200, only CD34+ dose remained significant for quantity of RBC and platelet transfusions. Analysis of time to transfusion independence demonstrated that patients with ABO major mismatches required longer to achieve freedom from RBC transfusion support compared to identical matches or those with minor mismatches.

CONCLUSION

Patient-specific factors including CD34+ dose and ABO match of the graft should be given particular consideration by transfusion services when planning support of patients receiving allogeneic hematopoietic stem cell transplant.

Peritransplantation Red Blood Cell Transfusion Is Associated with Increased Risk of Graft-versus-Host Disease after Allogeneic Hematopoietic Stem Cell Transplantation

More than 90% of allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients receive red blood cell (RBC) or platelet transfusions in the peritransplantation period. We tested the hypothesis that transfusions are associated with the development of severe (grade III-IV) acute graft-versus-host disease (aGVHD) or mortality after allo-HSCT in a retrospective study of 322 consecutive patients receiving an allogeneic bone marrow or granulocyte colony-stimulating factor-mobilized blood stem cell graft for a hematologic malignancy. Counting transfused RBC and platelet units between day -7 pretransplantation and day +27 post-transplantation, but excluding transfusions administered after a diagnosis of aGVHD, yielded medians of 5 RBC units and 2 platelet units transfused. Sixty-three patients (20%) developed a maximal grade III-IV aGVHD with onset up to day +150 post-transplantation (median aGVHD onset of 28 days). HLA mismatch (hazard ratio [HR], 2.4; 95% confidence interval [CI], 1.2 to 4.7; P = .01), and transfusion of more than the median number of RBC units (HR, 2.1; 95% CI, 1.1 to 3.7; P = .02) were independently associated with greater risk of grade III-IV aGVHD in a multivariable analysis model. Disease risk strata (HR, 1.7; 95% CI, 1.2 to 2.4 for high risk versus low risk; P = .005) and transfusion of more than the median number of RBC units (HR, 1.4; 95% CI, 1.0 to 2.0; P = .054) were independently associated with inferior overall survival. These data support our hypothesis that peritransplantation RBC transfusions are associated with the risk of developing severe aGVHD and worse overall survival following allo-HSCT, and suggest that strategies to reduce routine RBC transfusion may favorably reduce the incidence and severity of GVHD.

ABO incompatibility in mismatched unrelated donor allogeneic hematopoietic cell transplantation for acute myeloid leukemia: A report from the acute leukemia working party of the EBMT

ABO incompatibility is commonly observed in stem cell transplantation and its impact in this setting has been extensively investigated. HLA-mismatched unrelated donors (MMURD) are often used as an alternative stem cell source but are associated with increased transplant related complications. Whether ABO incompatibility affects outcome in MMURD transplantation for acute myeloid leukemia (AML) patients is unknown. We evaluated 1,013 AML patients who underwent MMURD transplantation between 2005 and 2014. Engraftment rates were comparable between ABO matched and mismatched patients, as were relapse incidence [34%; 95% confidence interval (CI), 28-39; for ABO matched vs. 36%; 95% CI, 32-40; for ABO mismatched; P = .32], and nonrelapse mortality (28%; 95% CI, 23-33; for ABO matched vs. 25%; 95% CI, 21-29; for ABO mismatched; P = .2). Three year survival was 40% for ABO matched and 43% for ABO mismatched patients (P = .35), Leukemia free survival rates were also comparable between groups (37%; 95% CI, 32-43; for ABO matched vs. 38%; 95% CI, 33-42; for ABO mismatched; P = .87). Incidence of grade II-IV acute graft versus host disease was marginally lower in patients with major ABO mismatching (Hazard ratio of 0.7, 95% CI, 0.5-1; P = .049]. ABO incompatibility probably has no significant clinical implications in MMURD transplantation.

Nonmyeloablative allogeneic hematopoietic cell transplantation

Most hematological malignancies occur in older patients. Until recently these patients and those with comorbidities were not candidates for treatment with allogeneic hematopoietic transplantation because they were unable to tolerate the heretofore used high-dose conditioning regimens. The finding that many of the cures achieved with allogeneic hematopoietic transplantation were due to graft-versus-tumor effects led to the development of less toxic and well-tolerated reduced intensity and nonmyeloablative regimens. These regimens enabled allogeneic engraftment, thereby setting the stage for graft-versus-tumor effects. This review summarizes the encouraging early results seen with the new regimens and discusses the two hurdles that need to be overcome for achieving even greater success, disease relapse and graft-versus-host disease.

ABO blood group antigen mismatch has an impact on outcome after allogeneic peripheral blood stem cell transplantation

ABO blood group antigen incompatibility (ABO mismatch) is not an obstacle to allogeneic stem cell transplantation (allo-SCT). However, the impact on clinical outcome after allo-SCT remains controversial. We analyzed 512 patients after allogeneic peripheral blood SCT (allo-PBSCT) for an association of ABO mismatch with transfusion requirements, myeloid and platelet engraftment, the incidence of GvHD, relapse, transplant-related mortality (TRM), and overall survival (OS). A total of 260 patients underwent ABO-mismatched transplantation and the control group consisted of 252 patients with ABO-matched allo-PBSCT. We found a significant association between major-0 ABO mismatch (group 0 recipient/group A, B, or AB donor) and increased red blood cell (RBC) and platelet transfusion requirements (both P<.001) as well as delayed platelet engraftment (P<.001). Minor-A (group A recipient/group 0 donor) and minor-AB (group AB recipient/group 0, A, or B donor) ABO mismatch was significantly associated with an increased TRM after allo-PBSCT (P=.001 and P=.02). In multivariate analysis performed using Cox regression, minor ABO mismatch appeared as independent risk factor for TRM after allo-PBSCT. No association was found for ABO mismatch with the incidence of GvHD, relapse, and OS. Our results suggest that ABO blood group mismatch has a significant impact on the outcome and that minor-A and minor-AB ABO mismatch represents a risk factor for increased TRM after allo-PBSCT.

ABO blood group incompatibility as an adverse risk factor for outcomes in patients with myelodysplastic syndromes and acute myeloid leukemia undergoing HLA-matched peripheral blood hematopoietic cell transplantation after reduced-intensity conditioning

BACKGROUND

ABO incompatibility is not a contraindication to hematopoietic cell transplantation (HCT), but it has been associated with additional risks including delayed engraftment, pure red cell aplasia (PRCA), and higher transfusion needs. Data on these events and on patient survival after reduced-intensity conditioning (RIC) HCT are limited.

STUDY DESIGN AND METHODS

A total of 127 consecutive patients, 86 with acute myeloid leukemia and 41 with myelodysplastic syndromes, who underwent HLA-matched peripheral blood RIC allogenic HCT between 2005 and 2014 were retrospectively analyzed.

RESULTS

Eighty ABO-compatible, 26 major/bidirectional, and 21 minor-ABO-mismatch HCT were identified. Compared to the ABO-compatible group, major/bidirectional mismatches had increased red blood cell (RBC) transfusion requirement during the first 100 days (p = 0.009), delayed RBC and PLT engraftment (p = 0.0011 and p = 0.005, respectively), and higher incidence of grade II to IV acute graft-versus-host disease (aGVHD; p = 0.037). In multivariable analysis, major/bidirectional mismatches had significantly higher non-relapse mortality (NRM) and inferior disease-free survival (DFS) and overall survival (OS) compared with ABO-compatible patients (p = 0.01, p = 0.04, and p = 0.035, respectively). Minor ABO mismatch had no impact on survival (p = 0.99). Four (15%) of 26 major/bidirectional mismatches developed PRCA. There was a significant association between fludarabine plus busulfan conditioning and PRCA (p = 0.0046).

CONCLUSION

Major/bidirectional ABO mismatch is associated with higher NRM and shortened DFS and OS in the setting of RIC HCT. Increased transfusion need, delayed RBC and platelet engraftment, PRCA, and increased severity of aGVHD are additional complications contributing to the morbidity.

Impact of ABO blood group mismatch in alemtuzumab-based reduced-intensity conditioned haematopoietic SCT

The impact of ABO incompatibility on clinical outcomes following haematopoietic SCT (HSCT) remains controversial. This retrospective study assessed the effect of ABO mismatch on transplant outcomes and transfusion requirements in 594 patients undergoing reduced-intensity conditioned (RIC) HSCT with alemtuzumab in three UK transplant centres. We found no significant effects of minor, major or bidirectional ABO mismatch on overall survival, relapse-free survival, nonrelapse mortality or relapse incidence. Although the rate of acute GVHD was unaffected by ABO mismatch, the incidence of extensive chronic GVHD was higher in patients with minor and major mismatch compared with those who were ABO matched (hazard ratio (HR) 1.74, P=0.032 for minor, HR 1.69 P=0.0036 for major mismatch). Red cell and platelet transfusion requirements in the first 100 days post transplant did not differ by ABO mismatch. In this large UK series, ABO mismatch in RIC HSCT has no clinically significant effect on survival outcomes but appears to modify susceptibility to extensive chronic GVHD.

Allogeneic peripheral blood stem cell transplantation using reduced-intensity conditioning in an outpatient setting in ABO-incompatible patients: are survival and graft-versus-host disease different?

BACKGROUND

Graft-versus-host disease (GVHD) is a major cause of morbimortality after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Minor ABO incompatibility has been associated with an increased risk of GVHD. We analyzed the impact of ABO matching on patient outcome after peripheral blood, reduced-intensity allo-HSCT in an outpatient setting, and its relationship with GVHD.

STUDY DESIGN AND METHODS

Data of 121 patients were included. All patients received allo-HSCT from HLA-identical siblings as outpatients using a reduced-intensity conditioning regimen. Influence of ABO matching as a risk factor for the development of GVHD and survival was analyzed using logistic regression and Cox proportional hazards regression, respectively.

RESULTS

Median age was 36 years (range, 1-71 years); 88 patients were ABO identical: 13 presented major mismatch and 20 minor mismatch, with an ABO incompatibility rate of 27.3%. The median follow-up period was 54 months (range, 0.3-120 months). Minor ABO incompatibility patients presented the highest rate of acute GVHD (aGVHD; 25%), in comparison with ABO-identical (20.5%) and major ABO incompatibility patients (15.4%; p = 0.79). The highest incidence of chronic GVHD (cGVHD) occurred in the context of minor ABO incompatibility (35%), in contrast to ABO-identical (30.8%) and major ABO incompatibility (15.4%). Survival was higher for patients in the minor ABO mismatch group; however, there was no significant correlation between ABO matching status and survival (p = 0.45).

CONCLUSION

Using this type of peripheral blood stem cell transplantation, minor ABO-mismatched allo-HSCT was associated with a higher incidence of aGVHD and cGVHD and with increased survival, albeit with no significance.

Impact of ABO-mismatch on risk of GVHD after umbilical cord blood transplantation

Recent advances in allogeneic hematopoietic cell transplant (allo-HCT) have led to an increasing use of alternative donors, including banked umbilical cord blood (UCB). Despite these advances, acute GVHD (aGVHD) and chronic GVHD (cGVHD) continue to be the leading causes of early and late transplant-related mortality. ABO-mismatch has been frequently reported as a risk factor for GVHD, however, data in the UCB recipients are limited. We hypothesized that as the lymphocytes in the cord blood are thought to be naive, they will therefore be less likely to mediate GVHD. Therefore, we analyzed the impact of ABO-mismatch on aGVHD and cGVHD in recipients of single and double UCB-HCT. In both univariate and multivariate analyses, presence of ABO-mismatch did not have an impact on aGVHD or cGVHD. Whereas ABO-compatible donors are preferred in recipients of URD-HCT, ABO compatibility generally need not be considered in recipients of UCB-HCT.

Advances in predicting acute GVHD

Acute graft-versus-host disease (GVHD) is a leading cause of non-relapse mortality following allogeneic haematopoietic cell transplantation. Attempts to improve treatment response in clinically-established GVHD have not improved overall survival, often due to the increased risk of infectious complications. Alternative approaches to decrease GVHD-related morbidity and mortality have focused on the ability to predict GVHD prior to clinical manifestation in an effort to provide an opportunity to abort GVHD development, and to gain new insights into GVHD pathophysiology. This review outlines the research efforts to date that have identified clinical and laboratory-based factors that are predictive of acute GVHD and describes future directions in developing algorithms that will improve the ability to predict the development of clinically relevant GVHD.

Clinical observation of factors in the efficacy of blood component transfusion in patients following hematopoietic stem cell transplantation

BACKGROUND

Factors affecting the efficacy of platelet and red blood cell (RBC) transfusion in patients undergoing hematopoietic stem cell transplantation (HSCT) have not been studied extensively. We aimed to evaluate platelet and RBC transfusion efficacy by measuring the platelet corrected count increment and the hemoglobin increment, respectively, 24 h after transfusion in 105 patients who received HSCT.

METHODOLOGY/PRINCIPAL FINDINGS

Using retrospective analysis, we studied whether factors, including gender, time of transplantation, the compatibility of ABO group between HSC donors and recipients, and autologous or allogenic transplantation, influence the efficacy of blood component transfusion. We found that the infection rate of HSCT patients positively correlated with the transfusion amount, and the length of stay in the laminar flow room was associated with transfusion. We found that platelet transfusion performed during HSCT showed significantly better efficacy than that performed before HSCT. The effect of platelet transfusion in auto-transplantation was significantly better than that in allo-transplantation. The efficacy of RBC transfusion during HSCT was significantly lower than that performed before HSCT. The efficacy of RBC transfusion in auto-transplantation was significantly higher than that in allo-transplantation. Allo-transplantation patients who received HSCs from compatible ABO groups showed significantly higher efficacy during both platelet and RBC transfusion.

CONCLUSIONS

We conclude that the efficacy of platelet and RBC transfusions does not correlate with the gender of patients, while it significantly correlates with the time of transplantation, type of transplantation, and ABO compatibility between HSC donors and recipients. During HSCT, the infection rate of patients positively correlates with the transfusion amount of RBCs and platelets. The total volume of RBC units transfused positively correlates with the length of the patients' stay in the laminar flow room.

Cytopenias after day 28 in allogeneic hematopoietic cell transplantation: impact of recipient/donor factors, transplant conditions and myelotoxic drugs

BACKGROUND

Secondary cytopenias are serious complications following hematopoietic cell transplantation. Etiologies include myelotoxic agents, viral infections, and possibly transplant-related factors such as the intensity of the conditioning regimen and the source of stem cells.

DESIGN AND METHODS

We retrospectively analyzed data from 2162 hematopoietic cell transplant recipients to examine the effect of these factors on overall cytopenias occurring after 28 days in hematopoietic cell transplantation.

RESULTS

Advanced age of the patient, recipient cytomegalovirus seropositivity, unrelated donor status, human leukocyte antigen mismatch and lower doses of transplanted CD34(+) cells (≤ 6.4×10(6)/kg) significantly increased the risk of cytopenias after day 28. Non-myeloablative hematopoietic cell transplantation had protective effects on anemia and thrombocytopenia after day 28 (adjusted odds ratio 0.76, probability value of 0.05 and adjusted odds ratio 0.31, probability value of <0.0001, respectively) but not on overall or ganciclovir-related neutropenia. This lack of protection appeared to be due to the use of mycophenolate mofetil in the majority of recipients of non-myeloablative hematopoietic cell transplants. Peripheral blood stem cells did not confer protection from cytopenias when compared to bone marrow.

CONCLUSIONS

Elderly patients appear to be more prone to cumulative toxicities of post-transplant drug regimens, but non-myeloablative conditioning, optimized human leukocyte antigen matching, and higher doses of CD34(+) cell infusions may reduce the risk of cytopenia after day 28.

[Pathogen inactivation of platelets: organization consequences for platelet transfusion]

In the past few years, pathogen reduction technologies for labile blood products have been part of the enhancement of global transfusion safety regarding residual risks of transmitting infectious pathogens. Having carried out a feasibility study for the implementation of pathogen inactivation of platelet concentrates by means of the amotosalen/HCl/UVA (Intercept™) technology, and participated to a reinforced haemovigilance study, we took the opportunity to analyze the organization consequences for platelet concentrates inventory and distribution. This impact study first indicated that those novel needs forced the blood donation service, as well as the labile blood product preparation laboratory, to review and improve practices; secondly, it showed that the routine implementation has little (no major) consequence in the overall organization, independently of the economic consequences (not covered here).