Alexei Maschan

Successful treatment of pure red cell aplasia with a single dose of rituximab in a child after major ABO incompatible peripheral blood allogeneic stem cell transplantation for acquired aplastic anemia

Pure red cell aplasia (PRCA) is a well-known although infrequent hematologic complication after allogeneic bone marrow transplantation. PRCA occurs in cases of major ABO-mismatch between donor and recipient and is believed to be due to inhibition of donor erythroid progenitors by residual host isohemagglutinins. We report a 10-year-old boy with post-hepatitis aplastic anemia (AA) who developed PRCA after HLA-matched familial peripheral blood stem cell transplantation (SCT) following conditioning with Cph 200 mg/kg + ATG 90 mg/kg. Granulocyte engraftment occurred on day +18, platelet engrafted on day +40, while reticulocytopenia at 0% persisted until day +118, and erythroid precursors were totally absent from bone marrow. After a single dose of rituximab 200 mg/m2administered on day +118 PRCA resolved and on day +132 the reticulocytes rose to 5.7%. On day +139 the Hb reached 137 g/l and the erythroid lineage in BM increased to 21%. We conclude that due to the rapid recovery from PRCA and lack of side effects, rituximab should be tried as first-line treatment of PRCA after allo-SCT.

Current outcome of HLA identical sibling versus unrelated donor transplants in severe aplastic anemia: an EBMT analysis

We have analyzed 1448 patients with acquired aplastic anemia grafted between 2005 and 2009, and compared outcome of identical sibling (n=940) versus unrelated donor (n=508) transplants. When compared to the latter, sibling transplants were less likely to be performed beyond 180 days from diagnosis (39% vs. 85%), to have a cytomegalovirus negative donor/recipient status (15% vs. 23%), to receive antithymocyte globulin in the conditioning (52% vs. 61%), and more frequently received marrow as a stem cell source (60% vs. 52%). Unrelated donor grafts had significantly more acute grade II–IV (25% vs. 13%) and significantly more chronic graft-versus-host disease (26% vs. 14%). In multivariate analysis, the risk of death of unrelated donor grafts was higher, but not significantly higher, compared to a sibling donor (P=0.16). The strongest negative predictor of survival was the use of peripheral blood as a stem cell source (P<0.00001), followed by an interval of diagnosis to transplant of 180 days or more (P=0.0005), patient age 20 years or over (P=0.0005), no antithymocyte globulin in the conditioning (P=0.003), and donor/recipient cytomegalovirus sero-status, other than negative/negative (P=0.04). In conclusion, in multivariate analysis, the outcome of unrelated donor transplants for acquired aplastic anemia, is currently not statistically inferior when compared to sibling transplants, although patients are at greater risk of acute and chronic graft-versus-host disease. The use of peripheral blood grafts remains the strongest negative predictor of survival.

TCR-alpha/beta and CD19 depletion and treosulfan-based conditioning regimen in unrelated and haploidentical transplantation in children with acute myeloid leukemia

We evaluated the depletion of TCR-alpha/beta cells from the graft of children with high-risk AML, who received transplantation from unrelated (n=20) and haploidentical donors (n=13). The preparative regimen included treosulfan, melphalan, fludarabine and anti-thymocyte globulin. Grafts were PBSC engineered by TCR-alpha/beta and CD19 depletion. The graft contained a median of 9 × 106/kg of CD34+ and 20 × 103/kg of αβ-T cells. Post-transplant immune suppression included tacrolimus till day +30 and Mtx in 21 patients, tacrolimus in 5, Mtx in 2 and no prophylaxis in 5 patients. Sixteen patients received native or TCR-alpha/beta-depleted donor lymphocytes at a median of 47 (40–204) days. Median follow-up is 1.76 years. Primary engraftment was achieved in 33 patients (100%). Cumulative incidence of acute GvHD (aGvHD) grade 2–3 was 39 (26–60)%, half of them had skin-only aGvHD. Cumulative incidence of chronic GvHD was 30(18–50)%. Transplant-related mortality is 10(4–26)%. Event-free survival (EFS) is 60(43–76)% and overall survival (OS) is 67(50–84)% at 2 years. In a subgroup of patients, who received transplantation in CR, EFS is 66(48–84)% and OS−72(53–90)% at 2 years. Our data suggest that TCR-alpha/beta and CD19 depletion is a robust method of graft manipulation, which can be used to engineer grafts for children with AML

Haematopoietic stem cell transplantation in children in eastern European countries 1985-2004 : development, recent activity and role of the EBMT/ESH Outreach Programme

The paediatric population of 19 eastern European countries amounts to approximately 80 million children. Between 1985 and 2004, the number of centres performing haematopoietic stem cell transplantation (HSCT) in children increased from 1 in 1985 to 24 in 2004 and the yearly number of paediatric HSCTs rose from 1 in 1985 to 291 in 2004. Altogether, 2342 transplants were reported to the EBMT Registry during this time (Poland 953, Czech Republic 501, Hungary 269, Russia 217, Croatia 129, Slovakia 71, Bulgaria 45, Serbia and Montenegro 36, Slovenia 35, Belarus 33, Estonia 26, Lithuania 19 and Romania 8). Out of the 2342 transplants, 1487 (63.5%) transplants were performed in paediatric centres, 453 (19.3%) in centres for adults and 402 (17.2%) in combined centres. The number of children who underwent autologous HSCT (auto-HSCT) was 1053 (45%), whereas 1289 (55%) underwent allogeneic HSCT (allo-HSCT). Peripheral blood (PB) was the source of HSC in 751 (71.3%) out of 1053 auto-transplants, BM in 246 (23.4%) and PB+BM in 52 (4.9%) (missing data in 4, that is, 0.4%). Among the 1289 allo-transplants, BM was the source of HSC in 827 (64.3%), PB in 416 (32.3%), CB in 23 (1.8%) and BM+PB in 14 (1.1%) (missing data in 9, that is, 0.7%). Among them, 728 (57.4%) obtained HSC from MSD, 322 (25.4%) from UD, 195 (15.4%) from MMFD, 14 (1.1%) from CB family donor and 9 (0.7%) from CB unrelated donor (missing data in 21, that is, 1.6%). The number of children who underwent allo-HSCT for malignant diseases was 945 (73.4%), including ALL 376 (29.2%), AML 234 (18.2%), CML 177 (13.8%), MDS 97 (7.5%), NHL 35 (2.7%) and other malignancy 31 (2.4%), while 339 (26.9%) for non-malignant disorders, including SAA 202 (15.7%), immunodeficiencies 61 (4.7%), inborn errors of metabolism 40 (3.1%), Fanconi anaemia 19 (1.5%) and others 17 (1.3%). Out of 1053 recipients of auto-HSCT, 168 (16%) were transplanted for neuroblastoma, 129 (12.2%) for NHL, 124 (11.7%) for AML, 114 (10.8%) for ALL, 109 (10.4%) for Hodgkins disease, 62 (5.9%) for Ewings sarcoma, 16 (1.5%) for CNS tumour, 15 (1.4%) for Wilms tumour and 316 (30%) for other tumours. In 2001, the EBMT in collaboration with the European School of Haematology (ESH) developed the Outreach Programme, that is a programme supporting emerging HSCT projects and transplant centres in countries with limited resources and/or experience.

Fludarabine, low-dose busulfan and antithymocyte globulin as conditioning for Fanconi anemia patients receiving bone marrow transplantation from HLA-compatible related donors.

Summary:Allogeneic hematopoietic stem cell transplantation (SCT) from unaffected donors remains the only modality for the correction of hematological abnormalities in Fanconi anemia (FA) patients. We performed four HLA-matched related donor SCT using a novel irradiation and cyclophosphamide-free conditioning regimen. The protocol included fludarabine 150 mg/m2, busulfan 4 mg/kg, and antithymocyte globulin 90 mg/kg. Graft-versus-host disease (GVHD) prophylaxis was cyclosporin A, MTX, and daclizumab. The engraftment and occurrence of full stable donor hemopoiesis was rapid in all cases with minimal short-term toxic complications. There were no infections or febrile episodes during the inpatient phase. Three patients developed acute GVHD grade I–II involving gut and skin and one patient progressed to extensive chronic GVHD. The preparative conditioning regimen is safe and associated with low organ toxicity and effective immunosupression for the stable engraftment in FA patients undergoing SCT with matched related donors.

Risk Factors for and the Clinical Impact of Cytomegalovirus and Epstein-Barr Virus Infections in Pediatric Recipients of TCR-α/β– and CD19-Depleted Grafts

Alpha/beta T cell and CD19 depletion are used to improve the outcomes of hematopoietic stem cell transplantation (HSCT). We evaluated the burden of cytomegalovirus (CMV) and Epstein-Barr virus (EBV) in pediatric patients after this HSCT type. A cohort of 182 patients with malignant (n = 114) or nonmalignant (n = 68) disorders was transplanted from either matched unrelated (n = 124) or haploidentical (n = 58) donors. The cumulative incidence of CMV and EBV viremia were 51% and 33%, respectively. Acute graft-versus-host disease (GVHD) grades II to IV, D-/R+ serology, and malignant HSCT indications were associated with increased risk of CMV viremia. CMV disease developed in 10 patients (6%). The occurrence of CMV viremia was not associated with inferior outcomes. Acute GVHD grade ≥ II was the only factor significantly associated with an increased risk of EBV viremia. Rituximab significantly decreased the rate of EBV reactivation in a subgroup that received a higher B cell dose in the graft. The rate of EBV-associated disease was .5%, and EBV viremia did not affect survival. TCR-α/β and CD19 depletion are associated with a significant rate of CMV viremia that does not affect survival. The hazard of EBV post-transplant lymphoproliferative disease (PTLD) is eliminated by the combination of CD19 depletion and rituximab.

Syngeneic transplantation in aplastic anemia: pre-transplant conditioning and peripheral blood are associated with improved engraftment: an observational study on behalf of the Severe Aplastic Anemia and Pediatric Diseases Working Parties of the European Group for Blood and Marrow Transplantation

Aplastic anemia is usually treated with immunosuppression or allogeneic transplant, depending on patient and disease characteristics. Syngeneic transplant offers a rare treatment opportunity with minimal transplant-related mortality, and offers an insight into disease mechanisms. We present here a retrospective analysis of all syngeneic transplants for aplastic anemia reported to the European Group for Blood and Marrow Transplantation. Between 1976 and 2009, 88 patients received 113 transplants. Most transplants (n=85) were preceded by a conditioning regimen, 22 of these including anti-thymocyte globulin. About half of transplants with data available (39 of 86) were followed by posttransplant immunosuppression. Graft source was bone marrow in the majority of cases (n=77). Transplant practice changed over time with more transplants with conditioning and anti-thymocyte globulin as well as peripheral blood stem cells performed in later years. Ten year overall survival was 93% with 5 transplant-related deaths. Graft failure occurred in 32% of transplants. Risk of graft failure was significantly increased in transplants without conditioning, and with bone marrow as graft source. Lack of posttransplant immunosuppression also showed a trend towards increased risk of graft failure, while anti-thymocyte globulin did not have an influence. In summary, syngeneic transplant is associated with a significant risk of graft failure when no conditioning is given, but has an excellent long-term outcome. Furthermore, our comparatively large series enables us to recommend the use of pre-transplant conditioning rather than not and possibly to prefer peripheral blood as a stem cell source.

Results at a single centre of immunosuppression with cyclosporine A in 66 children with aplastic anaemia

A retrospective analysis of cyclosporine A (CsA) monotherapy administered to 66 children with aplastic anaemia (AA) at a single centre was carried out. The study was conducted on 66 children (F34/M32) with a median age of 10.5 years. 30 children (45%) achieved complete or partial remission within a median of 8 weeks. The response rate was 3/19 (16%) in cases of very severe aplastic anaemia (vSAA), 16/34 (47%) in severe aplastic anaemia (SAA) and 11/13 (85%) in nonSAA. 10 remitters (33%) relapsed after CsA cessation or dose tapering and six of those responded again on CsA alone. The only variable predictive for response was granulocyte count before treatment. The actuarial probability of survival was 51% at 4 years (85% in moderate AA, 50% in SAA and 32% in vSAA). The optimal dosage of CsA has yet to be established.

Second allogeneic stem cell transplant for aplastic anaemia: a retrospective study by the severe aplastic anaemia working party of the European society for blood and marrow transplantation

We analysed the outcome of a second allogeneic haematopoietic stem cell transplant (alloHSCT) in 162 patients reported to the European Society for Blood and Marrow Transplantation between 1998 and 2009. Donor origin was a sibling in 110 and an unrelated donor in 52 transplants, respectively. The stem cell source was bone marrow in 31% and peripheral blood in 69% of transplants. The same donor as for the first alloHSCT was used in 81% of transplants whereas a change in the choice of stem cell source was reported in 56% of patients, mainly from bone marrow to peripheral blood. Neutrophil and platelet engraftment occurred in 85% and 72% of patients, after a median time of 15 and 17 days, respectively. Grade II‐IV acute graft‐versus‐host disease (GVHD) and chronic GVHD occurred in 21% and 37% of patients, respectively. Graft failure (GF) occurred in 42 patients (26%). After a median follow‐up of 3·5 years, the 5‐year overall survival (OS) was 60·7%. In multivariate analysis, the only factor significantly associated with a better outcome was a Karnofsky/Lansky score ≥80 (higher OS). We conclude that a second alloHSCT is feasible rescue option for GF in SAA, with a successful outcome in 60% of cases.

Efficacy of plerixafor in children with malignant tumors failing to mobilize a sufficient number of hematopoietic progenitors with G-CSF

Mobilization of suitable amounts of PBSCs with granulocyte-CSF (G-CSF) can be difficult in children. We report the results of using plerixafor in pediatric patients who failed to mobilize progenitors with G-CSF-based regimens. Thirty-three patients, median age 9 years (range 1–18 years) and median weight 29 kg (range 10–85 kg) were enrolled into the study. After 4 days of G-CSF stimulation, the median CD34+ cell count in peripheral blood was 10.4 per μL (range 0.27–23.0 per μL). Plerixafor was administered subcutaneously (0.24 μg/kg in 30 patients and 0.3 μg/kg in 3 patients) 11–12 h before apheresis. At the time of apheresis, CD34+ cell counts increased to a median of 44.1 per μL (range 8.4–357.0 per μL), a median 4.4-fold increase. Two patients (6%) failed to mobilize. Thirty-one patients underwent apheresis and in 27 >2 × 106 CD34+ cells per kg of body weight were collected after one procedure. In total, 31 of 33 patients mobilized successfully and the median number of cryopreserved CD34+ cells was 5.6 × 106 /kg body weight (2.7 × 106–27.4 × 106). Twenty-four patients underwent transplantation. Engraftment was achieved in all but one patient, who died on day +9 after hematopoietic stem cell transplantation. The median time of neutrophil and platelet recovery was day +12 and +16, respectively. Our study confirms that plerixafor has impressive efficacy and very modest toxicity in children.