Cardiac morbidity and mortality in deferoxamine- or deferiprone-treated patients with thalassemia major.

Deferoxamine (DFO) therapy has been associated with improved survival of thalassemia patients. However, cardiac disease remains the main cause of death in those patients. In 1995, the oral chelator deferiprone became available for clinical use. We compared the occurrence of cardiac disease in patients treated only with DFO and in those whose therapy was switched to deferiprone during the period of observation, from January 31, 1995, to December 31, 2003. All patients with thalassemia major treated in 7 Italian centers who were born between 1970 and 1993 and who had not experienced a cardiac event prior to January 1995 were included. DFO only was given to 359 patients, and 157 patients received deferiprone for part of the time. A total of 3,610 patient-years were observed on DFO and 750 on deferiprone. At baseline, the 2 groups were comparable for age and sex, while ferritin levels were significantly higher in patients switched to deferiprone. Fifty-two cardiac events, including 10 cardiac deaths, occurred during therapy with DFO. No cardiac events occurred during deferiprone therapy or within at least 18 months after the end of it. In the setting of a natural history study, deferiprone therapy was associated with significantly greater cardiac protection than deferoxamine in patients with thalassemia major.

Graft rejection after unrelated donor hematopoietic stem cell transplantation for thalassemia is associated with nonpermissive HLA-DPB1 disparity in host-versus-graft direction.

The success of allogeneic hematopoietic stem cell transplantation (HSCT) from matched unrelated donors (UDs) for beta-thalassemia may be hampered by the occurrence of graft rejection. Here, we show that the rate of this complication can be reduced by selecting 5-loci HLA-matched donors without nonpermissive mismatches at HLA-DPB1, defined according to an algorithm previously described and based on principles of central T-cell tolerance. Seventy-two consecutive patients and their UDs, prospectively selected for matching at the allelic level for HLA-A, -B, -C, -DRB, and -DQB1 loci, were enrolled in the analysis. These pairs were either DPB1 matched/permissively mismatched (n = 45, control group) or had at least one nonpermissive DPB1 mismatch in the host-versus-graft (HvG; n = 17) or in the graft-versus-host (GvH; n = 10) direction. In multivariate analysis, the risk of rejection was significantly increased in the group with HvG disparity (RR = 7.42; 95% CI = 1.29-42.68; P = .02) as compared to the control group. A lower, statistically significant, probability of thalassemia-free survival was found in patients belonging to the HvG group as compared to controls (RR = 5.15; 95% CI = 1.58-16.82; P = .01). These data suggest that in patients with thalassemia, the incidence of graft failure after HSCT may be reduced by appropriate selection of UDs, with such selection taking into account the functional rules of immunogenetics.

Unrelated bone marrow transplantation for beta-thalassemia patients: The experience of the Italian Bone Marrow Transplant Group.

Bone marrow transplantation (BMT) remains the only potentially curative treatment for patients with thalassemia major. However, most candidates for BMT do not have a suitable family donor. In order to evaluate whether BMT from an HLA-matched unrelated volunteer donor can offer a probability of cure comparable to that obtained when the donor is a compatible sibling, we carried out a study involving 68 thalassemia patients transplanted in six Italian BMT Centers. Thirty-three males and 35 females (age range, 2-37 years; median age, 15) were transplanted from unrelated volunteer donors, all selected using high-resolution molecular typing of both HLA class I and II loci. Fourteen patients were classified in risk class 1; 16 in risk class 2; and 38 in risk class III of the Pesaro classification system. Nine patients (13%) had either primary or secondary graft failure. Fourteen patients (20%) died from transplant-related causes. Grade II-IV acute graft-versus-host disease (GVHD) developed in 24 cases (40%), and chronic GVHD in 10 cases (18%). Overall survival (OS) in the cohort of 68 patients was 79.3% (CI 67-88%), whereas the Kaplan-Meier estimates of disease-free survival (DFS) with transfusion independence was 65.8% (CI 54-77%). In the group of 30 thalassemic patients in risk classes 1 and 2, the probability of OS and DFS were 96.7% (CI 90-100%) and 80.0% (CI 65-94%), respectively, whereas in the 38 patients in class 3 OS was 65.2% (CI 49-80%) and DFS was 54.5% (CI 38-70%). These data show that when donor selection is based on stringent compatibility criteria, the results of unrelated transplantation in thalassemia patients are comparable to those obtained when the donor is a compatible sibling.

B lymphocyte reconstitution after hematopoietic stem cell transplantation: functional immaturity and slow recovery of memory CD27+ B cells.

OBJECTIVE: Functional recovery of B lymphocytes after hematopoietic stem cell transplantation (HSCT) can take up to 2 years. HSCT recipients may obtain protective titers of pathogen-specific antibody through vaccination, but optimal timing of reimmunization remains to be defined. PATIENTS AND METHODS: In this study, we evaluated the reconstitution of B-cell number and activity in 139 children given HSCT, by B-cell subset phenotyping and in vitro immunoglobulin (Ig) production. RESULTS: Patients were longitudinally studied at 3, 6, 12, and 18 to 24 months after transplantation. At all time points, recipients displayed a significantly higher percentage of naive (IgD+CD27-) B cells and showed significantly lower production of stimulated in vitro Ig as compared to healthy controls. Moreover, during follow-up, we observed an increase in the proportion of patients who had CD27+ B subsets and who were able to mount in vitro Ig production greater than the 5th percentile. CONCLUSION: Similar to what has been described in adults, most children lack memory B cells and produce low amounts of Ig. However, the number of B cells, as well as their function, gradually recovered over time and the spread of data we observed suggests that the reimmunization schedule should be individualized for each patient. It remains to be defined in a prospective clinical study the time point at which a patient should start reimmunization. A reasonable hypothesis to be explored is the time point at which a percentage of memory B cells greater than the 5th percentile of normal controls is reached.

Survival and complications in patients with thalassemia major treated with transfusion and deferoxamine.

BACKGROUND AND OBJECTIVES: Seven Italian centers reported data on survival, causes of death and appearance of complications in patients with thalassemia major. The interactions between gender, birth cohort, complications, and ferritin on survival and complications were analyzed. DESIGN AND METHODS: Survival after the first decade was studied for 977 patients born since 1960 whereas survival since birth and complication appearance was studied for the 720 patients born after 1970. Better survival was demonstrated for patients born in more recent years (p<0.00005) and for females (p=0.0003); 68% of the patients are alive at the age of 35 years. In the entire population 67% of the deaths were due to heart disease. RESULTS: There was a significant association between birth cohort and complication-free survival (p<0.0005). The prevalence of complications was: heart failure 6.8%, arrhythmia 5.7%, hypogonadism 54.7%, hypothyroidism 10.8%, diabetes 6.4%, HIV infection 1.7%, and thrombosis 1.1%. Lower ferritin levels were associated with a lower probability of heart failure (hazard ratio =3.35, p<0.005) and with prolonged survival (hazard ratio = 2.45, p<0.005), using a cut-off as low as 1,000 ng/mL. INTERPRETATION AND CONCLUSIONS: Survival and complication-free survival of patients with thalassemia major continue to improve, especially for female patients born shortly before or after the availability of iron chelation.

Familial platelet disorder with propensity to acute myelogenous leukemia: genetic heterogeneity and progression to leukemia via acquisition of clonal chromosome anomalies.

Familial platelet disorder with propensity to acute myelogenous leukemia, or FPD/AML (OMIM #601399), is a rare autosomal dominant condition, with only 12 families reported. It is characterized by qualitative and quantitative platelet defects and predisposition to the development of myeloid malignancies. Causal mutations have been identified in the RUNX1 gene (also known as AML1, CBFA2) in the 11 families so far analyzed. RUNX1 is a gene frequently involved in the pathogenesis of sporadic leukemia and myelodysplastic syndromes, through acquired chromosome rearrangements and point mutations. We report an Italian family with three members affected with FPD/AML, two sibs and their father, who developed myelodysplastic syndromes (which in one subsequently evolved into AML). Direct sequencing and polymorphisms haplotype analysis of the region of chromosome 21 where RUNX1 is mapped demonstrated that FPD/AML in this family was not caused by any mutation of the RUNX1 gene, thus providing evidence for the genetic heterogeneity of this disorder. Cytogenetic studies showed monosomy 7 in the marrow of all the three affected subjects, as well as an independent clone with trisomy 8 in the father. The importance of mutator effects in the pathogenesis of familial myeloid malignancies characterized by relevant chromosome changes, in the presence or absence of an underlying Mendelian disorder, has already been suggested. Our results and a review of the cytogenetic literature led us to postulate that mutations also causing FPD/AML may have a mutator effect that could give origin to myelodysplastic syndromes and acute myeloid leukemias through acquired chromosome changes.

Reconstitution dynamics of plasmacytoid and myeloid dendritic cell precursors after allogeneic myeloablative hematopoietic stem cell transplantation.

Dendritic cells (DCs) are fundamental for immunity. We investigated reconstitution of plasmacytoid DC (PDC) and myeloid DC (My-DC) precursors in the first 2 months after allogeneic hematopoietic stem cell transplantation (Allo-HSCT). Circulating DCs were monitored from the earliest phase of hematopoietic reconstitution in 43 children given standard therapy to prevent graft-versus-host disease (GVHD) and either treated or untreated with granulocyte colony-stimulating factor (G-CSF) after HSCT. In patients without GVHD, both My-DCs and PDCs reached consistently high absolute values during the initial phase. Time of engraftment did not differ between My-DCs and PDCs, regardless of administration of G-CSF. Treatment with G-CSF (1) accelerated early recovery of My-DC absolute numbers; (2) was associated with lower numbers of both My-DCs and PDCs in the later phase; and (3) significantly reduced the proportion of interleukin-12 (IL-12)-secreting cells. In some patients who developed acute GVHD, we found high numbers of circulating DC precursors during the early phase of this complication. However, treatment with steroids invariably induced rapid decrease of PDCs. Altogether, these data provide an evaluation of DC release after Allo-HSCT, indicate that postgrafting administration of G-CSF impairs the appearance of IL-12-producing DCs, and suggest that DC homeostasis may be disrupted at onset of GVHD.

Human cytomegalovirus immediate-early mRNAemia versus pp65 antigenemia for guiding pre-emptive therapy in children and young adults undergoing hematopoietic stem cell transplantation: a prospective, randomized, open-label trial.

In the search for better protocols of preemptive therapy of human cytomegalovirus (HCMV) infection in hematopoietic stem cell transplant (HSCT) recipients, we conducted a randomized trial comparing antigenemia with the nucleic acid sequence-based assay (NASBA) for determination of HCMV immediate-early messenger RNA (IEmRNA) as the guiding assay for initiation of pre-emptive antiviral treatment. In the IEmRNA arm, antiviral therapy was started upon IEmRNA positivity confirmed the following day, whereas in the antigenemia arm, therapy was started in the presence of either at least 2 pp65-positive leukocytes/2 x 105 examined or a single positive leukocyte confirmed the following day. In both arms, treatment was stopped upon 2 consecutive negative results. All patients were monitored for 3 months after HSCT. The primary end point of the study was duration of anti-HCMV therapy. On the whole, 80 children (41 in the IEmRNA and 39 in the antigenemia arm), recipients of transplants from either a relative or an unrelated donor, completed the study. No patient developed HCMV disease. In the IEmRNA arm, the incidence of HCMV infection was higher compared to the antigenemia arm (80% vs 51%, respectively, P =.0069), as well as the percentage of treated patients (66% vs 44%, respectively, P =.045). However, the percentage of relapses and treated relapses was comparable in the 2 arms. There was no significant difference in median duration of therapy per patient. Although these data indicate that IEmRNA determination does not offer advantages in terms of treatment duration, it can safely replace antigenemia, while semiautomation is the major advantage of the NASBA procedure.

Rituximab for the treatment of refractory autoimmune hemolytic anemia in children.

Autoimmune hemolytic anemia (AIHA) in children is sometimes characterized by a severe course, requiring prolonged administration of immunosuppressive therapy. Rituximab is able to cause selective in vivo destruction of B lymphocytes, with abrogation of antibody production. In a prospective study, we have evaluated the use of rituximab for the treatment of AIHA resistant to conventional treatment. Fifteen children with AIHA were given rituximab, 375 mg/m(2)/dose for a median of 3 weekly doses. All patients had previously received 2 or more courses of immunosuppressive therapy; 2 patients had undergone splenectomy. After completing treatment, all children received intravenous immunoglobulin for 6 months. Treatment was well tolerated. With a median follow-up of 13 months, 13 patients (87%) responded, whereas 2 patients did not show any improvement. Median hemoglobin levels increased from 7.7 g/dL to a 2-month posttreatment level of 11.8 g/dL (P <.001). Median absolute reticulocyte counts decreased from 236 to 109 x 10(9)/L (P <.01). An increase in platelet count was observed in patients with concomitant thrombocytopenia (Evans syndrome). Three responder patients had relapse, 7, 8, and 10 months after rituximab infusion, respectively. All 3 children received a second course of rituximab, again achieving disease remission. Our data indicate that rituximab is both safe and effective in reducing or even abolishing hemolysis in children with AIHA and that a sustained response can be achieved in the majority of cases. Disease may recur, but a second treatment course may be successful in controlling the disease.

Unrelated donor bone marrow transplantation for thalassemia: the effect of extended haplotypes.

Allogeneic bone marrow transplantation (BMT) from a genotypically identical family donor is an accepted therapeutic option for homozygous beta-thalassemia. However, only a minority of patients have access to this curative procedure. The aim of this study is to explore the feasibility of matched unrelated transplants in thalassemia and the possibility of reducing the risk of immunologic complications through careful selection of donor/recipient pairs. Since November 1992, 32 patients (age range, 2-28 years) have been enrolled. There were 4 patients assigned to risk-class I, 11 to risk-class II, and 17 to risk-class III of the Pesaro classification. Extended haplotype analysis and family segregation studies were employed for identification of suitable donors. Of the 32 donor/recipient pairs, 24 were identical for HLA-A, B, C, DRB1, DRB3, DRB4, DRB5, DQA1, and DQB1 loci; 7 pairs were identical for 2 extended haplotypes, and 15 pairs shared one extended haplotype. Grade II-IV acute graft-versus-host disease (GVHD) developed in 11 cases (41%) and chronic GVHD in 6 (25%) out of 24 patients at risk. There are 22 patients (69%) who are alive and transfusion-independent after a median follow-up of 30 months (range, 7-109 months). There were 6 patients (19%) who engrafted and subsequently died from transplant-related complications. In 4 cases (12.5%) graft rejection was observed within 30 days and it was followed by autologous reconstitution. Out of 22 patients with a donor identical for at least one extended haplotype, there are 19 who survived, 17 of them being transfusion-independent. Among the 10 recipients who did not share any extended haplotype with the donor, only 5 are alive without thalassemia and 3 patients died. Of the 6 patients who died, 5 belonged to risk-class III and only 1 to risk-class II. BMT from well-selected unrelated donors may offer results comparable to those obtained in transplantations using HLA-identical family donors, especially for patients with lesser iron overload.

Anti-CD20 monoclonal antibody (Rituximab) for life-threatening autoimmune haemolytic anaemia in a patient with systemic lupus erythematosus.

Innovative approaches are needed for patients with systemic lupus erythematosus (SLE) who develop autoimmune haemolytic anaemia (AIHA) that does not respond to conventional treatment. Rituximab, a chimaeric anti-CD20 monoclonal antibody, has been demonstrated to be highly effective for in vivo B-cell depletion. We report an 18-year-old-girl with SLE and life-threatening AIHA that did not respond to steroids, intravenous immunoglobulin and cyclosporin A. Rituximab was given weekly at 375 mg/m2 for two doses. The drug was well tolerated and the patient had no adverse effects. Her haemolytic disorder markedly ameliorated, with a progressive increase of haemoglobin levels, starting a few days after therapy. The patient remains disease-free 7 months later.