Early and fatal immune haemolysis after so-called 'minor' ABO-incompatible peripheral blood stem cell allotransplantation

What is the role of complement in bystander hemolysis? Old concept, new insights

INTRODUCTION

Bystander hemolysis occurs when antigen-negative red blood cells (RBCs) are lysed by the complement system. Many clinical entities including passenger lymphocyte syndrome, hyperhemolysis following blood transfusion, and paroxysmal nocturnal hemoglobinuria are complicated by bystander hemolysis.

AREAS COVERED

The review provides data about the role of the complement system in the pathogenesis of bystander hemolysis. Moreover, future perspectives on the understanding and management of this syndrome are described.

EXPERT OPINION

Complement system can be activated via classical, alternative, and lectin pathways. Classical pathway activation is mediated by antigen-antibody (autoantibodies and alloantibodies against autologous RBCs, infectious agents) complexes. Alternative pathway initiation is triggered by heme, RBC microvesicles, and endothelial injury that is a result of intravascular hemolysis. Thus, C5b is formed, binds with C6-C9 compomers, and MAC (C5b-9) is formulated in bystander RBCs membranes, leading to cell lysis. Intravascular hemolysis, results in activation of the alternative pathway, establishing a vicious cycle between complement activation and bystander hemolysis. C5 inhibitors have been used effectively in patients with hyperhemolysis syndrome and other entities characterized by bystander hemolysis.

ABO subgroup incompatibility with severe hemolysis after consecutive allogeneic stem cell transplantations

Allogeneic hematopoietic stem cell transplantations (HSCTs) represent a curative strategy for treating hematologic malignancies yet bear dangerous and frequently life-threatening complications including the development of graft-versus-host disease. Here, we present a case of a patient that suffered from relapsed/refractory multiple myeloma, a hematologic neoplasm characterized by clonal proliferation of malignant plasma cells in the bone marrow. During the course of his disease, the patient underwent consecutive allogeneic HSCTs, during which he developed a clinical meaningful and hitherto unreported ABO subgroup incompatibility, leading to persistent hemolysis. Testing for ABO subgroups during donor selection, especially after consecutive allogeneic HSCTs, may therefore aid to prevent these complications.

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.

An update on ABO incompatible hematopoietic progenitor cell transplantation

Hematopoietic progenitor cell (HPC) transplantation has long been established as the optimal treatment for many hematologic malignancies. In the setting of allogenic HLA matched HPC transplantation, greater than 50% of unrelated donors and 30% of related donors demonstrate some degree of ABO incompatibility (ABOi), which is classified in one of three ways: major, minor, or bidirectional. Major ABOi refers to the presence of recipient isoagglutinins against the donor's A and/or B antigen. Minor ABOi occurs when the HPC product contains the isoagglutinins targeting the recipient's A and/or B antigen. Bidirectional refers to the presence of both major and minor ABOi. Major adverse events associated with ABOi HPC transplantation includes acute and delayed hemolysis, pure red cell aplasia, and delayed engraftment. ABOi HPC transplantation poses a unique challenge to the clinical transplantation unit, the HPC processing lab, and the transfusion medicine service. Therefore, it is essential that these services actively communicate with one another to ensure patient safety. This review will attempt to globally address the challenges related to ABOi HPC transplantation, with an increased focus on aspects related to the laboratory and transfusion medicine services.

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.

Hematopoietic SCT with cryopreserved grafts: adverse reactions after transplantation and cryoprotectant removal before infusion

Transplantation of hematopoietic stem cells (HSCs) has been successfully developed as a part of treatment protocols for a large number of clinical indications, and cryopreservation of both autologous and allogeneic sources of HSC grafts is increasingly being used to facilitate logistical challenges in coordinating the collection, processing, preparation, quality control testing and release of the final HSC product with delivery to the patient. Direct infusion of cryopreserved cell products into patients has been associated with the development of adverse reactions, ranging from relatively mild symptoms to much more serious, life-threatening complications, including allergic/gastrointestinal/cardiovascular/neurological complications, renal/hepatic dysfunctions, and so on. In many cases, the cryoprotective agent (CPA) used-which is typically dimethyl sulfoxide (DMSO)-is believed to be the main causal agent of these adverse reactions and thus many studies recommend depletion of DMSO before cell infusion. In this paper, we will briefly review the history of HSC cryopreservation, the side effects reported after transplantation, along with advances in strategies for reducing the adverse reactions, including methods and devices for removal of DMSO. Strategies to minimize adverse effects include medication before and after transplantation, optimizing the infusion procedure, reducing the DMSO concentration or using alternative CPAs for cryopreservation and removing DMSO before infusion. For DMSO removal, besides the traditional and widely applied method of centrifugation, new approaches have been explored in the past decade, such as filtration by spinning membrane, stepwise dilution-centrifugation using rotating syringe, diffusion-based DMSO extraction in microfluidic channels, dialysis and dilution-filtration through hollow-fiber dialyzers and some instruments (CytoMate, Sepax S-100, Cobe 2991, microfluidic channels, dilution-filtration system, etc.) as well. However, challenges still remain: development of the optimal (fast, safe, simple, automated, controllable, effective and low cost) methods and devices for CPA removal with minimum cell loss and damage remains an unfilled need.

Limiting the daily total nucleated cell dose of cryopreserved peripheral blood stem cell products for autologous transplantation improves infusion-related safety with no adverse impact on hematopoietic engraftment

Cryopreserved peripheral blood stem cell (PBSC) products can induce a number of infusion-related adverse reactions, including life-threatening cardiac, neurologic, and other end-organ complications. Preliminary analyses suggested limiting the daily total nucleated cell dose infused might decrease the incidence of these adverse effects. A policy change implemented in December 2007, limiting the total nucleated cell (TNC) dose to <1.63 × 10(9) TNC/kg/day, allowed us to assess the impact of this intervention on infusion-related safety, infusion schedules, engraftment, and costs in cohorts of patients undergoing autologous stem cell transplants (ASCTs) 2 years before (325 ASCTs in 288 patients) and 2 years after the policy change (519 ASCTs in 479 patients). The percentage of autologous transplant patients requiring multiple day infusions increased from 6% to 24%. Concurrently, the incidence of infusion-related grade 3-5 severe infusion-related adverse events (SAEs) decreased significantly, from 4% (13 of 325) prepolicy change to 0.6% (3 of 519) postpolicy change (P < .0004). Multiday infusions were not associated with increased time to neutrophil or platelet engraftment or the costs of transplantation. We conclude that limiting the daily TNC dose improved the safety of this procedure without compromising engraftment or increasing the costs of the procedure.

Significance of donor-derived isoagglutinins in ABO-Incompatible hematopoietic stem cell transplantation

Changes in isoagglutinin titers may have implications in the occurrence of hematological complications such as pure red cell aplasia or immune-mediated hemolysis. Furthermore, isoagglutinin titers could reflect immunohematological reconstitution after transplantation. The objective of this study was to examine the relationship between donor-derived isoagglutinins (DDIs) and graft-versus-host disease (GVHD). In total, 114 patients who underwent ABO-incompatible allogeneic hematopoietic stem cell transplantation (HSCT) were analyzed. Among these patients, 27.7% demonstrated increased donor-derived isoagglutinins (IDDIs) against red blood cells (RBCs) of the recipient, and 32.8% of the patients showed DDIs that were not against RBCs of the recipient. Patients with acute GVHD and DDIs against RBCs of the recipient tended to have higher incidences of IDDIs that occurred before posttransplant day 60 compared with patients without acute GVHD (17.3 vs. 3.9%, P=0.058). In patients with acute GVHD, IDDIs occurred significantly earlier (mean, day 32 vs. 181, P=0.046), the period of elevation was shorter (mean, day 36 vs. 134, P=0.033), and the donors were younger (mean, 28 vs. 36 years, P=0.01) than those without GVHD. Moreover, significant correlations were found between IDDIs and acute GVHD. Taken together, these data underscore a possible role for humoral immunity in GVHD after HSCT.

A 'dangerous' group O donor: severe hemolysis in all recipients of organs from a donor with multiple red cell alloantibodies

Alloimmune hemolysis is a recognized but infrequent complication of solid organ transplantation, particularly where there is incompatibility within the ABO blood group system. We describe severe hemolysis due to passenger lymphocyte syndrome (PLS) in all three recipients of organs from a single donor with multiple red cell (RC) alloantibodies. The first patient, a liver transplant recipient, required augmentation of immunosuppression to treat immune hemolysis due to anti-B, -D, -C and -Cellano (k). This is the first description of PLS caused by alloantibody to the high incidence RC antigen, k. The two single lung transplant recipients developed hemolysis due to anti-D. Both required escalation of immunosuppression and early transfusion support. Three months posttransplant, all three patients have ongoing evidence of compensated hemolysis. This series highlights the potential for severe non-ABO-mediated immune hemolysis following solid organ transplantation. A positive donor RC antibody screen should prompt careful monitoring of organ recipients for hemolysis.

[ABO incompatibility and non myeloablative allogeneic stem cell transplantation]

ABO incompatibility is not a barrier for allogeneic hematopoietic stem cell transplantation but is associated with specific complications. Major ABO incompatibility is associated with delayed erythroid engraftment, increased transfusion requirement and cases of pure red cell aplasia. Minor ABO incompatibility may be responsible for acute haemolytic reactions in the first months following transplantation. The widely used non myeloablative conditioning regimens might modify the management of ABO incompatibility. They could favour pure red cell aplasia development in the setting of major ABO mismatch since they are associated with a prolonged persistence of host anti-donor isohemagglutinins after allogeneic hematopoietic stem cell transplantation. In the setting of minor ABO incompatibility, the use of peripheral blood stem cells and the nature of graft-versus-host disease prophylaxis regimen may have an impact on the incidence of haemolytic reactions. In that review, the clinical and therapeutic aspects of ABO incompatibility are studied, especially regarding the impact of the conditioning regimen intensity.

ABO-histo blood group incompatibility in hematopoietic stem cell and solid organ transplantation

In contrast to solid organ transplantation (SOT), ABO-histo blood group incompatibility is of minor importance for hematopoietic stem cell transplantation (HSCT). Patients receiving ABO-incompatible HSCT are at an increased risk for immune-mediated hematological complications including immediate and delayed hemolysis, late red blood cell engraftment and pure red cell aplasia, but seem not to have a worse overall survival or increased transplant-related mortality. This review gives an overview of the immunological mechanisms leading to complications associated with ABO-incompatible HSCT and describes approaches to prevent them. The current organ shortage in SOT stimulates the exploration of new strategies to expand the donor pool including ABO-incompatible SOT and xenotransplantation. Here, we discuss the hypothesis that ABO-incompatible transplantation may be viewed as a human in vivo model for the humoral immune mechanisms of antigen-mismatched transplantation. ABO-incompatible HSCT and SOT provide excellent possibilities to analyze graft accommodation and transplantation tolerance. Understanding the underlying mechanisms of graft survival in ABO-incompatible transplantation may facilitate new strategies to overcome the immunological barriers in SOT and xenotransplantation.

Lack of isohemagglutinin production following minor ABO incompatible unrelated HLA mismatched umbilical cord blood transplantation

While immune hemolysis due to donor isohemagglutinin (IH) production often complicates minor ABO incompatible peripheral blood hematopoietic stem cell transplantation (PBSCT), it is not known if this occurs with umbilical cord blood transplantation (UCBT). We compared IH production and hemolysis following minor ABO allogeneic PBSCT and UCBT. We reviewed 24 ABO minor incompatible allogeneic PBSCTs and 14 ABO minor incompatible UCBTs. Patients were evaluated for donor-derived IH by reverse ABO grouping. Evaluation of hemolysis was based on clinical and laboratory findings of anemia associated with increased RBC transfusion need, concomitant with the appearance of donor-derived IH. Of the 24 ABO minor incompatible allogeneic PBSCTs, 15 produced donor-derived IH from 6 to 88 days following transplantation, with seven of 15 patients exhibiting clinically evident hemolysis. There was no significant difference in days to leukocyte engraftment or infused CD34 cells in patients with or without donor-derived IH. None of the 14 patients receiving ABO incompatible UCBTs showed evidence of donor-derived IH following transplantation with a median follow-up of 60 days. We conclude that donor IHs are not produced in patients undergoing minor ABO incompatible UCBTs suggesting fundamental immunologic differences between allogeneic PBSCT and UCBT.

Bystander Immune Cytolysis

In addition to alloimmune and autoimmune cell lysis, a third category of immune destruction of blood cells should be recognized. This additional immunologic response occurs when cells or tissues are injured by immunologic reactions in which the cells act as "innocent bystanders." One mechanism by which an immune response to an exogenous antigen leads to the destruction of autologous blood cells is the temporary development of autoantibodies. This is actually an alloimmune reaction which results in a temporary state of "pseudo"-autoimmunity. Although originally described as a type of hemolysis of autologous cells, the concept of bystander immune cytolysis has been extended to include other instances in which immune destruction of cells is caused by antibody that is not developed in response to intrinsic antigens on the cell being lysed. In recent years, compelling data have been presented documenting bystander immune cytolysis in a number of different clinical settings, and efforts have been made to define the mechanisms by which this occurs. Physicians must be aware that some examples of immune lysis of autologous cells are, in reality, examples of temporary bystander immune cytolysis rather than true autoimmune disease. Furthermore, some alloimmune hemolytic reactions can result in lysis of bystander cells.

Immune hemolysis associated with transplantation

Immune hemolysis is one of the adverse effects that can occur following hematopoietic cell or solid organ transplantation. Understanding the clinical settings and the various causes of immune hemolysis is necessary for prompt diagnosis and appropriate management. One of the important causes is the passenger lymphocyte syndrome, which occurs following minor ABO blood group incompatibility between donor and recipient. Hemolysis in this syndrome is often modest in severity but may be severe and even life-threatening. Major ABO blood group incompatibility is also associated with hemolysis, although this is relatively unusual and generally not severe. Autoimmune hemolytic anemia is a relatively common late complication of allogeneic transplantation and carries significant risk of mortality. Also, alloantibodies may be produced by engrafted cells of the donor's immune system or by residual cells of the patient's immune system following hematopoietic cell transplantation. Hemolysis may occur after solid organ transplantation, particularly as part of the passenger lymphocyte syndrome.

Safety and impact of donor-type red blood cell transfusion before allogeneic peripheral blood progenitor cell transplantation with major ABO mismatch

BACKGROUND

Changes within the ABO system are regularly observed phenomena in allogeneic bone marrow transplantation (BMT) and peripheral blood progenitor cell transplantation (PBPCT). Major ABO mismatch can lead to different clinical problems including acute hemolysis after infusion of the allograft, delay of red blood cell (RBC) engraftment, or even manifestation of pure red cell aplasia (PRCA).

STUDY DESIGN AND METHODS

This retrospective study demonstrates the safety and the impact of donor-type RBC transfusion before allogeneic PBPCT in major ABO settings as routinely performed at our transplantation unit. This study reports on transfusion of mismatched RBCs at the end of the conditioning period in 35 patients who underwent allogeneic PBPCT, which led to a decrease in isoagglutinin titers in most cases.

RESULTS

A decrease of isoagglutinin titer after donor-type RBC transfusion can significantly reduce the demand of RBC transfusion between transplantation and Day +30 (p = 0.003). Interestingly, patients who developed PRCA were not observed, a complication being regularly documented by other groups.

CONCLUSION

A decrease of isoagglutinin titers by in vivo immunoadsorption before allogeneic PBPCT does not only lack severe complication but also leads to a reduction in demand of RBC transfusion after engraftment and may reduce the incidence of PRCA in these patients.

Is the ABO incompatibility a risk factor in bone marrow transplantation?

ABO histo-bloodgroups are strong transplantation antigens. In bone marrow transplantation, foreign ABO red cell antigens are not ignored by the immune system of the host, neither by the immunocompetent cells of the graft. Although ABO incompatibility is not considered a contraindication in bone marrow transplantation (BMT), its clinical consequences are still a matter of investigation. An overview of reports published by different groups is given and discussed. They present conflicting data regarding the role of the ABO match between patient and donor in the haematopoietic stem cell (HSC) transplantation. We report on the clinical outcome of bone marrow transplantation in 223 patients who received grafts from MHC identical siblings. Included are 139 ABO identical, 32 ABO minor mismatched, 34 major mismatched and 13 bi-directionally mismatched pairs. The statistical evaluation of standard parameters used to monitor the post-transplant period gave a proof that in neither group of patients with an ABO incompatible donor the recovery and success rate of transplantation, including the relapse incidence, risk of graft vs. host disease (GVHD) or overall survival, were significantly inferior. However, in all three cohorts of ABO mismatched patients, a delayed recovery of neutrophils was recorded as compared to the group receiving an ABO compatible graft. These finding leads us to the conclusion that the ABO compatibility is not a disadvantage in BMT, whereas the delayed recovery of neutrophils in patients having received an ABO mismatched graft is probably reflecting a transient humoral process leading to immune tolerance and graft accommodation.

Impact of ABO incompatibility on outcome after allogeneic peripheral blood stem cell transplantation

Few studies have addressed the incidence of graft-versus-host disease (GVHD) or survival after ABO-incompatible allogeneic peripheral blood stem cell transplantation (PBSCT). We analyzed the clinical outcome of ABO incompatibility after allogeneic PBSCT. A total of 89 consecutive adult patients with hematological diseases including 49 ABO-identical, 20 major, 15 minor, and five bidirectional ABO-incompatible transplants were enrolled from four medical centers in Korea. No significant difference in engraftment times, graft failure, or transfusion requirements between groups was noted. A clinical diagnosis of severe immune hemolysis or pure red cell aplasia was not made for any patient after transplantation. The incidence of acute or chronic GVHD did not statistically differ between groups. With a median follow-up duration of 13 months (range, 0.5-61 months), the 3-year overall survival estimates for the ABO-identical, major/bidirectional, and minor group were 44.6.0+/-9.0, 43.1+/-11.6, and 43.8+/-13.5%, respectively (P=0.8652), while the 3-year disease-free survival estimates were 33.8+/-7.6, 39.9+/-11.4, and 45.7+/-13.1%, respectively (P=0.8546). We observed that time to neutrophil, platelet, and red blood cell engraftment, transfusion requirements, incidence of acute or chronic GVHD, relapse, and survival were not influenced by ABO incompatibility after allogeneic PBSCT from HLA-matched sibling donors.

Nonmyeloablative peripheral blood stem cell transplant for T-cell prolymphocytic leukaemia complicated by fulminant haemolysis and acute renal failure at engraftment secondary to minor ABO incompatibility

We present a 54-year-old man who underwent human leucocyte antigen-identical sibling nonmyeloablative peripheral blood stem cell transplant for primary refractory T-cell prolymphocytic leukaemia (T-PLL). His clinical course was complicated by fulminant haemolysis and acute renal failure at the time of engraftment because of minor ABO incompatibility between the donor and the recipient. This case highlights the curative potential of nonmyeloablative transplantation for T-PLL as well as the potential severity of immune haemolysis secondary to minor ABO incompatibility.

ABO-incompatible bone marrow transplantation: a GITMO survey of current practice in Italy and comparison with the literature

ABO incompatibility is not considered a contraindication for allogeneic haematopoietic stem cell transplantation (HSCT) despite its association with several immunohaematological complications. At present, there is no general agreement concerning the best methods to reduce these problems. To survey current practice related to ABO-incompatible HSCT in Italy, a questionnaire was sent to all GITMO centres. Specific questions were addressed for management in pretransplant, peritransplant and post transplant phases. A comparison was made with the experience reported in the literature. In all, 74% of GITMO centres answered the questionnaire. A high degree of heterogeneity concerning the pretransplant tests, methods to overcome infusion of ABO-incompatible marrow and post transplant transfusion policy and monitoring was evident. For many of these aspects the literature does not contain unanimous guidelines. The considerable degree of heterogeneity that reflects, at least partially, the lack of consensus in the literature demonstrates that ABO incompatibility is still an open issue in the setting of HSCT and that further studies are needed for a more rationale approach and for the production of evidence-based guidelines.

Transient anti rhesus alloantibody produced by graft after non-myeloablative allogeneic stem cell transplant

BACKGROUND

We report the case of a patient who received an allogeneic transplant with peripheral blood compatible ABO, Rhesus mismatched progenitor cells and who developed an asymptomatic transient anti Rhesus alloimmunisation.

CASE REPORT

A 56-year-old man with renal cell carcinoma received a non-myeloablative allogeneic PBPC ABO compatible graft from his HLA-identical brother. Graft-versus-host disease prophylaxis consisted of cyclosporine alone. On day + 59, prior to any transfusion, a positive direct antiglobulin test (IgG++, C3d-) was detected. The indirect antiglobulin test (IAT) was considered doubtful, and IAT identification revealed the presence of an active anti Rhesus antibody (anti D specificity) in the patient's serum. This immunisation had no clinical consequence, with no acute hemolytic episode. Further monitoring showed negative antibody screening tests on day + 78.

CONCLUSION

To our knowledge this is the first reported case of transient anti Rh (D) allo-immunisation after non-myeloablative allogeneic peripheral blood progenitor cell (PBPC) transplant. The period of occurrence and the specificity of this antibody strongly suggest a donor cell origin.

Impact of ABO incompatibility on allogeneic peripheral blood progenitor cell transplantation after reduced intensity conditioning

BACKGROUND

Most studies indicate that ABO incompatibility has no effect on the clinical outcome after allogeneic peripheral blood progenitor cell (PBPC) transplantation (allo-PBPCT). However, it carries additional risks of hemolytic reactions, delayed red blood cell (RBC) engraftment, and pure red cell aplasia (PRCA). Data on these events after reduced intensity conditioning (RIC) regimens are limited, but recent studies have suggested a higher transplant-related mortality (TRM) and morbidity in this setting.

STUDY DESIGN AND METHODS

We investigated the impact of ABO-matching on the outcome of 77 patients included in a prospective RIC allo-PBPCT protocol, focusing on engraftment, transfusion requirements, graft-versus-host disease, TRM, and survival.

RESULTS

There were 17 (22%) minor and 8 (10%) major ABO-incompatible transplants. No graft failures were observed. After major ABO-incompatible grafts, RBC engraftment was delayed, longer thrombocytopenia periods were documented, and transfusion requirements increased. A transient mild hemolysis occurred in 10 patients, 7 (41%) minor and 3 (37%) major ABO-mismatched. A PRCA was observed in a O+ patient with a pretransplant anti-Jka, grafted from an A + Jka+ donor. Graft-versus-host disease, disease progression, and TRM were not affected by ABO matching.

CONCLUSION

ABO incompatibility was not associated with clinically relevant hemolysis after the RIC protocol used and did not impair the clinical outcome. PRCA was only observed in one patient, with a non-ABO RBC allo-antibody.

ABO mismatch increases transplant-related morbidity and mortality in patients given nonmyeloablative allogeneic HPC transplantation

BACKGROUND

ABO mismatch has not been thought to affect the outcome of patients undergoing myeloablative conditioning and allogeneic HPC transplantation. Data on transplant-related complications after ABO-mismatched transplantation after nonmyeloablative conditioning are limited.

STUDY DESIGN AND METHODS

Therefore, 40 patients were analyzed after nonmyeloablative conditioning with regard to ABO compatibility. Eleven received a minor and bidirectional and 8 a major ABO-mismatched graft.

RESULTS

Four patients had evidence of hemolysis during engraftment, being lethal in one, and three developed pure RBC aplasia. Six patients in the ABO-mismatched group developed thrombotic microangiopathy, and three of them died. ABO-identical and ABO-mismatched patients had a similar incidence of GVHD. Viral infections occurred in both groups in equal shares. Patients with an ABO-mismatch had to be rehospitalized until Day 100 for a median of 19 days versus 0 days in the identical group (p < 0.05). Overall survival was 60 and 57 percent in the ABO-identical and ABO-mismatch groups, respectively. The probability of transplant-related mortality was 0 versus 28 percent in the identical group compared to patients with an ABO mismatch (p < 0.05). The probability of relapse or progression was 76 versus 25 percent in the ABO-identical group compared to the ABO-mismatched group, respectively.

CONCLUSION

Significantly more patients with ABO mismatch showed transplant-associated complications and died as a result of transplant-related causes.

[Immunohematologic follow-up and transfusion safety in hematopoietic stem cells allografts]

Since 1990, specific documentation is established between the immunohematology laboratory of the French EFS Lorraine-Champagne and the marrow transplantation unit of the CHU of Nancy, for patients undergoing hematopoietic stem cells transplantation. These documents and the standardization of the immunohematologic follow-up of those patients, have contributed to the improvement of the transfusion safety.

Changes of isoagglutinin titres after ABO-incompatible allogeneic stem cell transplantation

We investigated the changes in isoagglutinin titres in 62 patients who underwent ABO-incompatible allogeneic stem cell transplantation. After major [and/or (+/-) minor] ABO-incompatible transplantation, recipient-derived isoagglutinins against donor-type red blood cells (RBCs) disappeared more rapidly in unrelated recipients (P = 0.006) and in patients with acute graft-versus-host disease (GVHD, P = 0.025) than in sibling recipients and in patients without acute GVHD respectively. Pure red cell aplasia (PRCA) developed in 10 out of 35 evaluable patients who underwent major (+/- minor) ABO-incompatible transplantation, and the post-transplant increase of isoagglutinin titres was a significant predictor for the occurrence of PRCA. In five out of 36 patients who underwent minor (and/or (+/-) major) ABO-incompatible transplantation, donor-derived isoagglutinins against recipient RBCs were detectable without clinically overt haemolysis. Isoagglutinin titres against ABO antigens absent both on recipient and donor RBCs decreased during the early post-transplant period then rose subsequently in 24 out of 29 patients at (median) d 59 post transplant. Our study showed that changes in isoagglutinin titres might have clinical implications in the occurrence of immunohaematological complications such as PRCA or immune-mediated haemolysis, and might reflect immunohaematological reconstitution after transplantation. Furthermore, our data regarding time to disappearance of recipient-derived isoagglutinins against donor-type RBCs after major ABO-incompatible transplantation suggest the presence of a graft-versus-plasma cell effect.

Massive immune hemolysis after non-myeloablative allogeneic peripheral blood stem cell transplantation with minor ABO-incompatibility

A 35-year-old male, blood group B, Rh(D)+ type, received an allogeneic peripheral blood stem cell (PBSC) transplant after a non-myeloablative regimen of fludarabine and cyclophosphamide for resistant gammadelta cutaneous T-cell lymphoma (CTCL). The donor was his HLA-identical brother, blood group O, Rh(D)+ type. Graft-versus-host disease (GVHD) prophylaxis was performed with cyclosporine alone. On day +8, massive immune hemolysis occurred, followed by acute renal failure. Hemodialysis was performed eight times until recovery of renal function on day +24. The risk of delayed immune hemolysis after non-myeloablative allogeneic PBSC transplantation with minor ABO-incompatibility must be considered.

Severe immune hemolysis after minor ABO-mismatched allogeneic peripheral blood progenitor cell transplantation occurs more frequently after nonmyeloablative than myeloablative conditioning

BACKGROUND

Hemolysis as a result of donor-recipient minor ABO mismatching is a complication of allogeneic peripheral blood progenitor cell (PBPC) transplantation (PBPCT). The increased B-lymphocyte content of PBPC grafts and immunosuppressive regimens without methotrexate (MTX) may increase incidence and severity of this event.

STUDY DESIGN AND METHODS

A total of 93 patients were analyzed after allogeneic PBPCT. In 25 (27%) cases, minor (n=21) or bidirectional (n=4) ABO mismatching was present. Of these, 15 patients received myeloablative and 10 received nonmyeloablative conditioning regimens. For GVHD, prophylaxis cyclosporin A (CsA) alone (n=2) or CsA with MTX (n=13) was given after myeloablative conditioning and CsA with mycophenolate mofetil (MMF) after nonmyeloablative conditioning (n=10).

RESULTS

Hemolysis occurred in 4 out of 25 (16%) patients with minor or bidirectional ABO mismatching only. Three patients underwent nonmyeloablative conditioning and were given CsA with MMF, and one patient underwent myeloablative conditioning and was given CsA alone for GVHD prophylaxis. Hemolysis began 7 to 10 days after transplantation, and donor type alloantibodies were detectable concomitantly with recipients type RBCs.

CONCLUSION

Patients receiving minor or bidirectional ABO-mismatched PBPC grafts and GVHD prophylaxis without MTX are at risk of hemolysis. Prophylactic interventions in patients before minor ABO-mismatched PBPCT not receiving MTX should be taken into consideration. Careful monitoring of hemolysis parameters during the first 15 days after PBPCT transplantation is mandatory.

Impact of stem cell source and conditioning regimen on erythrocyte recovery kinetics after allogeneic haematopoietic stem cell transplantation from an ABO-incompatible donor

We evaluated erythrocyte recovery in 121 allogeneic haematopoietic stem cell transplantation (HSCT) recipients. There were 35 major and minor ABO-incompatible transplants, respectively, including 10 bi-directionally ABO-incompatible transplants. The use of peripheral blood stem cells facilitated erythrocyte recovery, regardless of the presence or absence of major ABO-incompatibility, and was associated with a frequent detection of anti-host isohaemagglutin early after minor ABO-incompatible transplantation, which was not associated with clinically relevant haemolysis. The use of a reduced-intensity regimen combining a purine analogue and busulphan did not delay erythrocyte recovery after major ABO-incompatible transplantation, suggesting this regimen had a strong activity against host plasma cell.

Donor anti-Jk(a) causing hemolysis in a liver transplant recipient

BACKGROUND

Hemolytic transfusion reactions have been observed in recipients of ABO- and/or D-mismatched marrow, peripheral blood, and solid organs. Passenger lymphocyte syndrome occurs when immunocompetent donor lymphocytes transferred during transplantation produce alloantibodies against host antigens.

CASE REPORT

The first case of a delayed, anti-Jk(a)-mediated hemolytic reaction in a liver transplant recipient, caused by passenger donor lymphocytes, is reported here. A 43-year-old man underwent liver transplantation. Six weeks later, the patient underwent a second liver transplant. On Day 10 of the second transplant, clinical hemolysis ensued; anti-Jk(a) was detected. The patient's DAT became positive, and anti-Jk(a) was eluted from his RBCs. On Day 35 of the patient's second transplant, 3 weeks after the last blood transfusion, the patients' DAT was still weakly positive with anti-Jk(a) in the eluate. Six months later, serum antibody screening was negative, but the DAT was still weakly positive. The patient's RBCs tested Jk(a+), whereas the second donor's RBCs were Jk(a-).

CONCLUSION

This is the first documentation of clinically significant hemolysis caused by anti-Jk(a), produced by passenger lymphocytes transferred from the donor's liver to the transplant recipient.

Posttransplant immune-mediated hemolysis

BACKGROUND

Immune-mediated hemolysis is a well-recognized complication of transplantation, but few reports have drawn together the different mechanisms that could be involved.

STUDY DESIGN AND METHODS

The clinical and laboratory records of three patients are used to illustrate different types and complexities of posttransplant immune-mediated RBC destruction.

RESULTS

Patient 1 received bone marrow from an HLA-matched, unrelated donor. At 7 months after transplant, his Hb level fell to 50 g per L. The serum contained warm autoantibodies, and the DAT was strongly positive for IgG, IgM, and C3d; an eluate yielded IgG and IgM autoantibodies. Autoimmune hemolytic anemia was diagnosed. Patient 2, blood group A, experienced severe hemolysis 14 days after receiving a lung from a group O donor. The DAT was positive for IgG. Serum and RBC eluate contained anti-A produced by immunocompetent B cells in the transplanted lung-this was the passenger lymphocyte syndrome. Patient 3 experienced posttransplant hemolysis caused by two different immune mechanisms. Originally group A, D- with anti-C, -D, -E, she received a peripheral blood progenitor cell (PBPC) transplant from her HLA-identical group A, D+ son. Six months later, chimerism was evident; the remaining recipient marrow was still producing antibodies that destroyed D+ RBCs made by the transplant. Later, autoimmune hemolytic anemia also developed; the DAT became positive for IgG, and warm autoantibodies were eluted from D- RBCs.

CONCLUSION

An understanding of the causes and circumstances under which posttransplant immune hemolysis arises is required for proper management. As more patients become long-term survivors of unrelated bone marrow and/or PBPC transplants, chimerism and complex serologic problems will become more common.

ABO mismatch may affect engraftment in multiple myeloma patients receiving nonmyeloablative conditioning

BACKGROUND

Blood group incompatibility does not appear to affect the overall outcome in patients undergoing myeloablative conditioning before allogeneic BMT. Data on ABO-mismatched transplantation in the nonmyeloablative setting are limited.

STUDY DESIGN AND METHODS

A retrospective analysis of the effects of ABO mismatches in multiple myeloma patients who received a nonmyeloablative conditioning regimen was conducted.

RESULTS

Three of 27 patients received a minor ABO-mismatched graft, all with evidence of hemolysis before converting to donor ABO group on Days 10, 15, and 6. Six patients received a major ABO-mismatched graft; of these, three developed GVHD of more than grade 2 and subsequently converted to the ABO blood group of the donor on Days 38, 33, and 43. Of the three patients without GVHD, one rejected the allograft and had autologous reconstitution. One remained a mixed chimera to Day 100 despite three donor lymphocyte infusions, and one developed pure RBC aplasia. None of the ABO-matched patients rejected the graft, whether they developed GVHD or not. RBC transfusions were significantly higher in the major and minor ABO-mismatched patients than in the ABO-matched patients, with medians of 12 units (range, 2-35), 13 units (range, 5-18), and 4 units (range, 2-15), respectively (p = 0.02). ABO-matched patients had a similar incidence of GVHD, with 5 of 9 ABO-mismatched patients (56%) having more than grade 2 versus 10 of 18 (56%). Four of 9 ABO-mismatched patients (44%) were mixed chimeras up to Day 100 versus 2 of 18 ABO-matched patients (11%), and the difference was significant (p = 0.01).

CONCLUSION

Patients with ABO mismatch had problems with engraftment, including graft rejection, pure RBC aplasia, and mixed-lineage chimerism. RBC transfusions were significantly higher in the ABO-mismatched recipients. GVHD may play a role in engraftment, possibly by facilitating the disappearance of native ABO antibodies via graft-versus-plasma cell effect. A prospective study to evaluate the effects of ABO mismatch on engraftment in the nonmyeloablative setting is needed.

Hematopoietic stem cell transplantation between red cell incompatible donor-recipient pairs

Transplantation between red cell-disparate donor and recipient is feasible with minimal increase in the risk of transplantation if consideration is given to the immunohematological consequences of the transplant. The risks of immediate and delayed hemolysis must be managed. Some recipients will experience a delay in the recovery of red blood cells.

Influence of the hematopoietic stem cell source on early immunohematologic reconstitution after allogeneic transplantation

Several acute hemolysis episodes, sometimes lethal, have been recently described after transplantation of allogeneic peripheral blood hematopoietic stem cells (PBHSCs). Hemolysis resulted from the production of donor-derived antibodies (Abs) directed at ABO antigens (Ags) present on recipient red blood cells (RBCs). A multicenter randomized phase III clinical study comparing allogeneic PBHSC transplantation (PBHSCT) versus bone marrow hematopoietic stem cell transplantation (BMHSCT) has been conducted in France. In the course of this study, serum anti-A and/or anti-B Ab titers were compared before the conditioning regimen and on day +30 after transplantation in 49 consecutive evaluable PBHSCT (n = 21) or BMHSCT (n = 28) recipients. PBHSCT resulted in a higher frequency of increased anti-A and/or anti-B Ab titers 30 days after transplantation as compared to BMHSCT: 8 (38%) of 21 versus 3 (11%) of 28 (P =.04). In PBHSCT recipients, increased titers were observed mostly after receiving a minor ABO mismatch transplant: 5 of 7 versus 3 of 14 in the absence of any minor ABO mismatch (P =.05), whereas this was not the case after BMHSCT: 1 of 8 versus 2 of 20. Anti-A and/or anti-B serum Abs detectable at day +30 after PBHSCT were always directed against A and/or B Ags absent both on donor and recipient RBCs. Finally, 3 of 21 PBHSCT versus 0 of 28 BMHSCT recipients developed anti-allogeneic RBC Abs other than ABO (P =.07). Overall, the data strongly suggest that immunohematologic reconstitution differs significantly after granulocyte colony-stimulating factor-mobilized PBHSCT when compared to BMHSCT. Such a difference could contribute to the acute hemolysis described after PBHSCT as well as to distinct alloreactivity after PBHSCT.

Massive immune haemolysis after allogeneic peripheral blood stem cell transplantation with minor ABO incompatibility

Immune haemolysis as a result of minor ABO incompatibility is an underappreciated complication of haematopoietic transplantation. The increased lymphoid content of peripheral blood stem cell (PBSC) transplants may increase the incidence and severity of this event. We observed massive immune haemolysis in 3 out of 10 consecutive patients undergoing HLA-identical, related-donor PBSC transplants with minor ABO incompatibility. Non-ablative conditioning had been given in 9 of these 10 cases, including two with haemolysis. Cyclosporin alone was used as prophylaxis against graft-vs.-host disease (GVHD). Catastrophic haemolysis of 78% of the circulating red cell mass led to anoxic death in the first case seen, but severe consequences were avoided by early, vigorous donor-compatible red cell transfusions in the subsequent two cases. Haemolysis began 7-11 d after PBSC infusion and all patients with haemolysis had a positive direct antiglobulin test (DAT), with eluate reactivity against the relevant recipient antigen. However, neither the intensity of the DAT, the donor isohaemagglutinin titre, nor other factors could reliably be used to predict the occurrence of haemolysis. Our data indicate that haemolysis may be frequent and severe after transplantation of minor ABO-incompatible PBSCs when utilizing cyclosporin alone to prevent GVHD. Meticulous clinical monitoring and early, vigorous donor-compatible red cell transfusions should be practiced in all instances.

Transplantation of ABO-incompatible bone marrow and peripheral blood stem cell components

Hemolysis may occur during infusion of an ABO-incompatible HSC component if the recipient has isoagglutinins directed against donor red blood cells, or later as a result of the production by donor lymphocytes of isoagglutinins directed against recipient ABO-antigens. Peripheral blood stem cell (PBSC) components collected by apheresis contain few red cells but considerably greater numbers of lymphocytes than marrow. We reviewed the transplant courses of 158 recipients of marrow (n = 90) or PBSC (n = 68) from HLA-identical, ABO-incompatible sibling donors. No patient experienced immediate or delayed hemolysis attributable to the ABO incompatibility. Recipients of minor ABO-incompatible red cell-replete marrow required fewer red cell transfusions during the first week after transplantation than recipients of PBSC or marrows depleted of red cells; the red cell transfusion requirements for the following 3 weeks did not differ. The maximum level of bilirubin did not differ for patients classified by ABO incompatibility or source of HSC. The development of positive antiglobulin tests occurred for eight marrow recipients from a separate group of 22 patients (17 marrow, five PBSC) for whom this testing was performed. None of these patients developed overt hemolysis. These data indicate that hemolysis complicating ABO-incompatible transplantation is not common after either marrow or PBSC transplantation. Bone Marrow Transplantation (2000) 26, 749-757.

Passenger lymphocyte syndrome with severe hemolytic anemia due to an anti-Jk(a) after allogeneic PBPC transplantation

BACKGROUND

After allogeneic peripheral blood progenitor cell (PBPC) transplantation, a patient developed a severe hemolytic transfusion reaction due to passenger lymphocyte syndrome.

CASE REPORT

A 50-year-old woman with secondary acute myeloid leukemia transforming from a myelodysplastic syndrome received an ABO-compatible PBPC graft from her HLA-identical sister. For prophylaxis of GVHD, the patient was treated with cyclosporine and methotrexate. Eighteen days after the transplant, the patient experienced a severe hemolytic transfusion reaction due to an alloantibody (anti-Jk(a)) produced by donor lymphocytes.

RESULTS

The patient was typed as group A, Jk(a+) before transplantation; the donor was typed as group A, Jk(a-). On Day 18 after transplantation, the immunohematologic screening revealed a positive DAT (C3d 3+) and an alloanti-Jk(a). Hemolysis in the patient at that time was indicated by a drop in the Hb and an increase in the LDH level (maximum, 592 IU/L on Day 23).

CONCLUSION

The course of hemolysis and the time of appearance of an alloantibody in this patient meet the criteria for passenger lymphocyte syndrome. In most cases, this syndrome is triggered by ABO system antibodies. This is the first reported case of passenger lymphocyte syndrome after PBPC transplantation that was due to an alloantibody that did not belong to the ABO system.

Allogeneic peripheral blood hematopoietic stem cell transplantation: guidelines for red blood cell immuno-hematological assessment and transfusion practice.Société Française de Greffe de Moelle

Allogeneic peripheral blood hematopoietic stem cell transplantation (PBSCT) is presently being evaluated in a French randomized study comparing peripheral blood vs bone marrow. Cases of potentially lethal acute hemolysis have recently been reported after allogeneic PBSCT in the presence of a 'minor' ABO incompatibility. Patients were frequently transfused with recipient-compatible and donor-incompatible RBC and usually did not receive methotrexate in addition to cyclosporin A for graft-versus-host disease (GVHD) prophylaxis. In order to homogenize immuno-hematological (IH) assessment and transfusion practices within our protocol, we made proposals to 25 allo-transplant French centers on the following aspects: pre-inclusion IH assessment, IH exclusion criteria, transfusion rules, post-transplant IH surveillance and treatment of hemolysis. Analysis of responses to our proposals led to the elaboration of guidelines which were approved and implemented by the French Bone Marrow Transplantation Society (SFGM). Pre-inclusion IH testing includes mandatory detection and titration of anti-RBC allo-Ab, as well as titration of anti-A and anti-B Ab. The presence in the donor of an anti-A (group A or AB recipients), anti-B (group B or AB recipients) Ab with a titer >1/32 or the presence of allo-Ab against Rh, Kell, Fya, Fyb, Jka, Jkb, Ss Ag present on recipient RBC is an exclusion criterion for the protocol. ABO and RhD compatibility of RBC blood products with both HSC donor and recipient is mandatory. A similar compatibility is also required for Rh (other than D) and Kell Ag. If not possible, compatibility of RBC blood products with the HSC donor is mandatory. Lastly, guidelines regarding post-transplantation IH follow-up as well as acute hemolysis treatment have been elaborated. The implementation of these guidelines should contribute to enhancing the quality of transfusion practice after PBSCT. Such an approach will be applied to other aspects of transfusion medicine in the setting of HSC transplantation. Bone Marrow Transplantation(2000) 25, 507-512.

Randomized trial of bone marrow versus lenograstim-primed blood cell allogeneic transplantation in patients with early-stage leukemia: a report from the Société Française de Greffe de Moelle

PURPOSE

To compare hematologic recovery in patients receiving allogeneic blood cell transplantation (BCT) with those receiving allogeneic bone marrow transplantation (BMT).

PATIENTS AND METHODS

One hundred eleven patients with leukemia in the early stages and with HLA-matched sibling donors were randomized in this study. One hundred one underwent transplantation. Standard procedures for collection and transplantation were used. Patients did not receive prophylactic granulocyte colony-stimulating factor after undergoing transplantation. In addition to clinical end points being established, a prospective and comparative economic evaluation of the first 6 months after transplantation was performed.

RESULTS

Groups were balanced for patient, donor, and transplant characteristics. Blood cell collection led to the collection of a higher number of CD34(+) and CD3(+) cells than did bone marrow collection (P < 10(-6)) without reported side effects for the donor. Patients in the BCT group reached platelet counts of 25 and 50 x 10(9) platelets/L 8 and 11 days earlier than did the BMT group (P < 10(-4) and P < 10(-5)), respectively. This resulted in fewer platelet transfusions during the first 180 days after transplantation (P =.002) for the former group. The time to reach neutrophil counts of 0.5 and 1 x 10(9) neutrophils/L was 6 and 7 days shorter, respectively, in the BCT group than in the BMT group (P < 10(-5)). This quicker hematologic recovery was associated with a shorter length of hospitalization and a decrease in total cost of procedure during the first 6 months.

CONCLUSION

This study establishes that allogeneic BCT results in quicker hematologic recovery but is associated with a higher occurrence of chronic graft-versus-host disease.

Delayed massive immune hemolysis mediated by minor ABO incompatibility after allogeneic peripheral blood progenitor cell transplantation

BACKGROUND

Bone marrow transplantation with minor ABO incompatibility may be followed by moderate delayed hemolysis of the recipient's red cells by donor-derived ABO antibodies. This reaction may be more severe after transplantation of peripheral blood progenitor cells (PBPCs).

CASE REPORT

A 16-year-old boy underwent an allogeneic PBPC transplant from his HLA-mismatched mother as treatment for acute myeloblastic leukemia that had proved resistant to induction chemotherapy. Transfusion of the unmanipulated PBPCs proceeded without any complication, despite the difference in ABO blood group (donor, O Rh-positive; recipient, A Rh-positive). On Day 7, a rapid drop in hemoglobin to 4 g per dL was observed, which was attributed to a massive hemolysis. All the recipient's group A red cells were destroyed within 36 hours. This delayed and rapidly progressive hemolytic anemia was not associated with the transfusion of the donor's plasma. Rather, the anti-A titer increased in parallel with marrow recovery, which suggested an active synthesis of these antibodies by immunocompetent cells from the donor against the recipient's red cells. The mother's anti-A titer was retrospectively found to be 2048. Her unusually high titer is probably due to prior sensitization during pregnancies. On Day 12, the patient developed grade IV graft-versus-host disease, which proved resistant to all treatments instituted and led to his death on Day 35.

CONCLUSION

PBPC transplantation with minor ABO incompatibility may be associated with significant risk of massive delayed hemolysis.

Apparent reactivation of a red cell alloantibody in a healthy individual after G-CSF administration

Granulocyte-colony stimulating factor (G-CSF) has been successfully administered to healthy subjects to mobilize peripheral blood stem cells (PBSC) for allogeneic transplantation. Adverse events are moderate. We report the first case of apparent reactivation of an alloantibody to a blood cell antigen (Jk(a)) after G-CSF administration to a healthy subject and its transmission to the PBSC transplant recipient; no concomitant reactivation of other alloantibodies was detected. This case raises questions on the effect of G-CSF on the immune system and its safety in healthy individuals.