Acquired aplastic anemia in childhood

Alternative treatment modality for severe aplastic anemia in a resource-limited setting: a single-institution prospective cohort study from Upper Egypt

This study compared the efficacy and safety of CsA monotherapy with eltrombopag (E-PAG) + CsA combined treatment in children with severe aplastic anemia (SAA). The study including 30 children had SAA. Ten were a retrospective cohort treated with CsA monotherapy. The other 20 were prospective cohort received E-PAG + CsA. All patients were evaluated for partial (PR) and complete (CR) hematological response at 3, 6, and 12 months. overall response (OR), overall survival rates (OS), and treatment safety. OR for the E-PAG patients was 40% after 3 months of therapy. At 6 months, this had increased to 75% with significantly higher CR rate (40%) than in the CsA group (p = 0.0001). After a year of treatment, the CR for the E-PAG + CsA regimen had increased to 50% and the OR to 85%, compared to 20% in the CsA group (p = 0.0001). The OS at 12 months was 100% in the E-PAG+ CsA group compared to 80% in the CsA cohort. At 24 months, the OS in the E-PAG + CsA group was 90%. In conclusion, E-PAG+ CsA was found to be a safe and effective alternative treatment for children with SAA particularly in countries with limited resources.

Patient features and survival of pediatric aplastic anemia in the USA: a large institution experience

BACKGROUND

We performed the first epidemiologic investigation to examine association of demographics and clinical characteristics at diagnosis, as well as health care expense coverage, with survival of US children with aplastic anemia (AA).

METHODS

We obtained electronic medical record data of 1140 children aged 0-19 years diagnosed with AA followed at a pediatric health system between 2004 and 2014. Kaplan-Meier curve and Cox proportional hazards regressions were used.

RESULTS

Self-pay patients had a mortality risk five times higher than that of those insured by publicly funded insurance (hazards ratio, 95% CI: 6.0, 3.7-9.8). Other features associated with higher mortality risk include pancytopenia (hazards ratio, referent: 4.2, constitutional AA); underweight (2.0, normal-weight); platelet count <50 × 109/l (1.3, ≥50 × 109/l); male sex (1.3, female); and ages at diagnosis 6-11, 11-16 and 16-19 years (1.6, 1.9, 2.3, 1-3 years), respectively.

CONCLUSIONS

Self-pay was the strongest prognostic factor for pediatric AA mortality. Older age, pancytopenia, underweight, male sex and lower platelet count were also associated with increased risk of mortality. These findings may be useful for providers, researchers and policymakers to ensure effective health care delivery to this population and to motivate future etiologic research and establishment of a surveillance registry.

Improved outcome of haploidentical transplantation in severe aplastic anemia using reduced-intensity fludarabine-based conditioning

Significant improvements in hematopoietic stem cell transplantation (HSCT) with haploidentical family donors (HFD) have confirmed its therapeutic role in severe aplastic anemia (SAA) and led to the evolution of treatment algorithms. However, the optimal conditioning regimen for HFD-HSCT remains undefined, especially the dosage of cyclophosphamide (Cy). A total of 77 patients with SAA from two research centers, who received HFD-HSCT with reduced-intensity fludarabine + cyclophosphamide + thymoglobulin ± busulfan conditioning regimen plus third-party cells infusion were included in this study, of which 67 pairs had 4-5 loci mismatched. We were particularly interested in whether the dosage of Cy significantly impacted graft failure (GF) and overall survival (OS). All patients showed sustained hematopoietic engraftment without any increase in severe aGVHD and transplantation-related mortality (TRM). The incidences of grade II-IV aGVHD, grade III-IV aGVHD and extensive cGVHD were 18%, 10% and 7%, respectively. The probabilities of 1-year and 5-year OS were 93.1% and 87.9%, respectively. Furthermore, patient age <15 years, MNC cells >8×10⁸/kg and donor age <45 years were associated with better survival (P=0.043, P=0.023, and P=0.037, respectively) and engraftment (P=0.019, P=0.008, and P=0.001, respectively). Our findings indicated that SAA patients lack MSD benefited the most if HFD-HSCT was performed with reduced-intensity fludarabine-based conditioning regimen. Improved outcomes with HFD-HSCT may lead to a salvaged therapy and an expanded direct role for SAA in the future.

Haploidentical hematopoietic stem cell transplantation in children and adolescents with acquired severe aplastic anemia

Severe aplastic anemia (SAA) is a life-threatening disorder for which allogeneic hematopoietic stem cell transplantation (HSCT) is the current available curative treatment. HSCT from matched sibling donors (MSDs) is the preferred therapy for children with acquired SAA. For patients who lack MSDs, immunosuppressive therapy (IST) is widely accepted as a first-line treatment before considering HCT from an unrelated donor (URD). Given the recent progress in HSCT using URDs for childhood SAA, well-matched URDs became a realistic alternative for pediatric patients who have no suitable related donors and who are refractory to IST. However, it is quite challenging to treat patients with refractory SAA who lack suitable related or URDs. Even though haploidentical HSCT from genetically mismatched family members seemed to be an attractive procedure with the amazing benefit of readily available donors for most patients, early attempts were disappointing because of refractory graft-versus-host disease (GVHD) and excessively high transplant-related mortality. Recent advances with effective ex vivo depletion of T cells or unmanipulated in vivo regulation of T cells, better supportive care, and optimal conditioning regimens have significantly improved the outcome of haploidentical transplant. Besides considerable progress in the treatment of malignant diseases, recent emerging evidences for haploidentical HSCT in SAA has provided additional therapeutic options for patients with refractory diseases. Further improvements to decrease the rates of graft failure, GVHD, and infectious complications will facilitate the emergence of haploidentical HSCT as a front-line therapy for treating acquired SAA in children and adolescents who have no suitably matched donors.

Matched related donor hematopoietic stem cell transplantation results in a long-term follow-up of a pediatric acquired severe aplastic anemia subset: A stem cell source perspective

HSCT has substantially improved pediatric acquired SAA patients' outcomes. Retrospectively, we attempted to assess the outcome of MRD HSCT in 65 pediatric patients referred to a single center from 1992 to 2012. We were particularly interested to find out whether source of SC (PB, n = 40 and BM, n = 25) significantly impacts EFS and GVHD incidence. With a median follow-up of 45 months, total EFS was 87.7%; EFS for PB and BM groups was 87.5% and 88%, respectively. Acute GVHD (grades 3-4) occurred in 13 patients (PB, n = 10 [25%] and BM, n = 3 [12%]), acute GVHD (grades 2-4) occurred in 24 (PB, n = 16 [40%] and BM, n = 8 [32%]). Extensive chronic GVHD occurred in five patients (PB, n = 3 [7.5%] and BM, n = 2 [8%]). Cox regression revealed that elapsed time of <10 months between diagnosis and HSCT is associated with improved survival (hazard ratio, 95% CI = 1.204, 1.010-1.434, p = 0.038). SC source did not significantly affect EFS, incidence of acute GVHD (grades 3-4), or extensive chronic GVHD (p = 0.938, 0.121, and 0.487, respectively). Based on our findings, pediatric acquired SAA patients are benefitted most if MRD-HSCT is carried out early in disease process and SC source does not affect outcome of MRD-HSCT in these patients.

Stem cell transplantation of matched sibling donors compared with immunosuppressive therapy for acquired severe aplastic anaemia: a Cochrane systematic review

OBJECTIVES

Acquired severe aplastic anaemia is a rare and potentially fatal disease. The aim of this Cochrane review was to evaluate the effectiveness and adverse events of first-line allogeneic haematopoietic stem cell transplantation of human leucocyte antigen (HLA)-matched sibling donors compared with first-line immunosuppressive therapy.

SETTING

Specialised stem cell transplantations units in primary care hospitals.

PARTICIPANTS

We included 302 participants with newly diagnosed acquired severe aplastic anaemia. The age ranged from early childhood to young adulthood. We excluded studies on participants with secondary aplastic anaemia.

INTERVENTIONS

We included allogeneic haematopoietic stem cell transplantation as the test intervention harvested from any source of matched sibling donor and serving as a first-line therapy. We included immunosuppressive therapy as comparator with either antithymocyte/antilymphocyte globulin or ciclosporin or a combination of the two. PRIMARY AND SECONDARY OUTCOME MEASURES PLANNED AND FINALLY MEASURED: The primary outcome was overall mortality. Secondary outcomes were treatment-related mortality, graft failure, graft-versus-host disease, no response to immunosuppressive therapy, relapse after initial successful treatment, secondary clonal disease or malignancies, health-related quality of life and performance scores.

RESULTS

We identified three prospective non-randomised controlled trials with a study design that was consistent with the principle of 'Mendelian randomisation' in allocating patients to treatment groups. All studies had a high risk of bias due to the study design and were conducted more than 15 years. The pooled HR for overall mortality for the donor group versus the no donor group was 0.95 (95% CI 0.43 to 2.12, p=0.90).

CONCLUSIONS

There are insufficient and biased data that do not allow any firm conclusions to be made about the comparative effectiveness of first-line allogeneic haematopoietic stem cell transplantation of HLA-matched sibling donors and first-line immunosuppressive therapy of patients with acquired severe aplastic anaemia.

Diagnosis and treatment of pediatric acquired aplastic anemia (AAA): an initial survey of the North American Pediatric Aplastic Anemia Consortium (NAPAAC)

BACKGROUND

Randomized clinical trials in pediatric aplastic anemia (AA) are rare and data to guide standards of care are scarce.

PROCEDURE

Eighteen pediatric institutions formed the North American Pediatric Aplastic Anemia Consortium to foster collaborative studies in AA. The initial goal of NAPAAC was to survey the diagnostic studies and therapies utilized in AA.

RESULTS

Our survey indicates considerable variability among institutions in the diagnosis and treatment of AA. There were areas of general consensus, including the need for a bone marrow evaluation, cytogenetic and specific fluorescent in situ hybridization assays to establish diagnosis and exclude genetic etiologies with many institutions requiring results prior to initiation of immunosuppressive therapy (IST); uniform referral for hematopoietic stem cell transplantation as first line therapy if an HLA-identical sibling is identified; the use of first-line IST containing horse anti-thymocyte globulin and cyclosporine A (CSA) if an HLA-identical sibling donor is not identified; supportive care measures; and slow taper of CSA after response. Areas of controversy included the need for telomere length results prior to IST, the time after IST initiation defining a treatment failure; use of hematopoietic growth factors; the preferred rescue therapy after failure of IST; the use of specific hemoglobin and platelet levels as triggers for transfusion support; the use of prophylactic antibiotics; and follow-up monitoring after completion of treatment.

CONCLUSIONS

These initial survey results reflect heterogeneity in diagnosis and care amongst pediatric centers and emphasize the need to develop evidence-based diagnosis and treatment approaches in this rare disease.

Outcome of pediatric acquired aplastic anemia: a developing world experience

INTRODUCTION

Outcome data of children with acquired aplastic anemia (AA) are lacking from the developing world. Here, we describe the same from a centre in North India.

METHODS

Retrospective data regarding medical history, physical examination, complete blood count, bone marrow aspirate, and biopsy were retrieved for all children <18 years, with acquired AA admitted between January 2005 and June 2012. In addition, the outcome data after immunosuppressive therapy (IST) or bone marrow transplant (BMT) was obtained.

RESULTS

A total of 61 children were diagnosed with AA (Inherited-18 and acquired-43). Among 43 children with acquired AA, 3 had nonsevere and 40 had severe. One patient with nonsevere AA died of sepsis and 2 recovered spontaneously. Of the 40 remaining children with severe AA, 10 refused therapy and 3 died due to severe sepsis prior to any therapy. Five underwent upfront matched sibling donor BMT and one post-IST failure. Four year overall survival (OS) and event free survival (EFS) for children undergoing BMT was 100% and 80 ± 17.9, respectively. Out of 22 treated with IST, 20 were evaluable for response. Seventeen received one course and 3 received two course of IST. The overall response to IST was seen in 14/20 (70%). Only two achieved complete response while remaining 12 had partial response. The 4-year estimated OS and EFS for children treated with IST was 74.4 ± 12.1% and 65.6 ± 12.2.

CONCLUSION

Outcomes for children with AA are encouraging in the developing world although barriers like sepsis and treatment abandonment remain. BMT offers faster and complete recovery.

First-line allogeneic hematopoietic stem cell transplantation of HLA-matched sibling donors compared with first-line ciclosporin and/or antithymocyte or antilymphocyte globulin for acquired severe aplastic anemia

BACKGROUND

Acquired severe aplastic anemia is a rare and potentially fatal disease, which is characterized by hypocellular bone marrow and pancytopenia. The major signs and symptoms are severe infections, bleeding, and exhaustion. First-line allogeneic hematopoietic stem cell transplantation (HSCT) of a human leukocyte antigen (HLA)-matched sibling donor (MSD) is a treatment for newly diagnosed patients with severe aplastic anemia. First-line treatment with ciclosporin and/or antithymocyte or antilymphocyte globulin (as first-line immunosuppressive therapy) is an alternative to MSD-HSCT and is indicated for patients where no MSD is found.

OBJECTIVES

To evaluate the effectiveness and adverse events of first-line allogeneic hematopoietic stem cell transplantation of HLA-matched sibling donors compared to first-line immunosuppressive therapy including ciclosporin and/or antithymocyte or antilymphocyte globulin in patients with acquired severe aplastic anemia.

SEARCH METHODS

We searched the electronic databases MEDLINE (Ovid), EMBASE (Ovid), and The Cochrane Library CENTRAL (Wiley) for published articles from 1946 to 22 April 2013. Further searches included trial registries, reference lists of recent reviews, and author contacts.

SELECTION CRITERIA

The following prospective study designs were eligible for inclusion: randomized controlled trials (RCTs) and non-randomized controlled trials if the allocation of patients to treatment groups was consistent with 'Mendelian randomization'. We included participants with newly diagnosed severe aplastic anemia who received MSD-HSCT or immunosuppressive therapy without prior HSCT or immunosuppressive therapy, and with a minimum of five participants per treatment group. We did not apply limits on publication year or languages.

DATA COLLECTION AND ANALYSIS

Two review authors abstracted the data on study and patient characteristics and assessed the risk of bias independently. We resolved differences by discussion or by appeal to a third review author. The primary outcome was overall mortality. Secondary outcomes were treatment-related mortality, graft failure, no response to first-line immunosuppressive therapy, graft-versus-host-disease (GVHD), relapse after initial successful treatment, secondary clonal and malignant disease, health-related quality of life, and performance score.

MAIN RESULTS

We identified three trials that met the inclusion criteria. None of these trials was a RCT. 302 participants are included in this review. The three included studies were prospectively conducted and had features consistent with the principle of 'Mendelian randomization' as defined in the present review. All studies had a high risk of bias due to the study design. All studies were conducted more than 10 years ago and may not be applicable to the standard of care of today. Primary and secondary outcome data showed no statistically significant difference between treatment groups. We present results for first-line allogeneic hematopoietic stem cell transplantation of an HLA-matched sibling donor, which we denote as the MSD-HSCT group, versus first-line treatment with ciclosporin and/or antithymocyte or antilymphocyte globulin, which we denote as the immunosuppressive therapy group in the following section.The pooled hazard ratio for overall mortality for the MSD-HSCT group versus the immunosuppressive therapy group was 0.95 (95% confidence interval 0.43 to 2.12, P = 0.90, low quality evidence). Therefore, overall mortality was not statistically significantly different between the groups. Treatment-related mortality ranged from 20% to 42% for the MSD-HSCT group and was not reported for the immunosuppressive therapy group (very low quality evidence). The authors reported graft failure from 3% to 16% for the MSD-HSCT group and GVHD from 26% to 51% (both endpoints not applicable for the immunosuppressive therapy group, very low quality evidence). The authors did not report any data on response and relapse for the MSD-HSCT group. For the immunosuppressive therapy group, the studies reported no response from 15% (not time point stated) to 64% (three months) and relapse in one of eight responders after immunosuppressive therapy at 5.5 years (very low quality evidence). The authors reported secondary clonal disease or malignancies for the MSD-HSCT group versus the immunosuppressive therapy group in 1 of 34 versus 0 of 22 patients in one study and in 0 of 28 versus 4 of 86 patients in the other study (low quality evidence). None of the included studies addressed health-related quality of life. The percentage of the evaluated patients with a Karnofsky performance status score in the range of 71% to 100% was 92% in the MSD-HSCT group and 46% in the immunosuppressive therapy group.

AUTHORS' CONCLUSIONS

There are insufficient and biased data that do not allow any conclusions to be made about the comparative effectiveness of first-line allogeneic hematopoietic stem cell transplantation of an HLA-matched sibling donor and first-line treatment with ciclosporin and/or antithymocyte or antilymphocyte globulin (as first-line immunosuppressive therapy). We are unable to make firm recommendations regarding the choice of intervention for treatment of acquired severe aplastic anemia.

Immunosuppressive therapy in aplastic anemia

OBJECTIVE

To assess the response to antithymocyte globulin based immunosuppressive therapy (IST) in pediatric patients with idiopathic aplastic anemia.

METHODS

Thirty patients (19 boys and 11 girls) with aplastic anemia received antithymocyte globulin and cyclosporine. Twenty-two patients had severe and 8 had very severe aplastic anemia.

RESULTS

Mean age of the patients was 9.19 ± 2.56 y. Three patients died within 1 mo of therapy, two due to sepsis and one due to intracranial hemorrhage. Twenty-seven patients were analyzed for response to therapy. Eight patients (29.7%) responded at 3 mo: 3 complete response (CR) and 5 partial response (PR). Six mo after the therapy, overall response (OR) was seen in 9/27 (33.3%), with one more patient in no response group achieving partial response. At 1 year, patients in CR maintained their status and 1 patient in PR group relapsed. He again achieved partial response with repeat course of ATG. Responders had significantly shorter duration of illness and higher absolute neutrophil count as compared to non responders to IST. None of the patients developed acute leukemia in the follow up.

CONCLUSIONS

The treatment of aplastic anemia in pediatric patients is a challenging task. One third of the patients achieved overall response which included both complete and partial response.

Survival after immunosuppressive therapy in children with aplastic anemia

OBJECTIVE

To determine the survival of children =18 y, treated with immunosuppressive therapy (IST) using equine antithymocyte globulin (e-ATG) and cyclosporine (CsA).

DESIGN

Prospective data entry as per a specified format.

SETTING

Tertiary care hospital.

PATIENTS

From January 1998 to December 2009, 40 children were diagnosed with acquired aplastic anemia; 33 patients, who received IST, were analyzed. 31 children (94%) received one course of e-ATG and CsA. 2 patients (6%) received two courses of ATG.

INTERVENTION

Immunosuppressive therapy using equine ATG and cyclosporine.

MAIN OUTCOME MEASURES

Overall response and overall survival.

RESULTS

The overall response (complete response + partial response) to IST at 6 months was 87.9%. 8 (24.2%) patients achieved CR, 21 (63.6%) patients had PR and 4 (12.1%) patients did not respond to IST. Median follow-up was 24 (6-102) months. Overall survival at 24 months was 90%, with an actual survival of 85.4% at 5 years. Seventeen patients (51.5%) received G-CSF for a median duration of 32 (23-64) days. The patients who received G-CSF had fewer infectious complications (P=0.002), but G-CSF administration did not influence survival/ outcome. No patient developed myelodysplastic syndrome or acute leukemia.

CONCLUSIONS

The survival of patients who respond to IST is excellent. Also, G-CSF reduces the infectious complications without conferring any survival advantage.

First-line matched related donor hematopoietic stem cell transplantation compared to immunosuppressive therapy in acquired severe aplastic anemia

Introduction

Acquired severe aplastic anemia (SAA) is a rare and progressive disease characterized by an immune-mediated functional impairment of hematopoietic stem cells. Transplantation of these cells is a first-line treatment option if HLA-matched related donors are available. First-line immunosuppressive therapy may be offered as alternative. The aim was to compare the outcome of these patients in controlled trials.

Methods

A systematic search was performed in the bibliographic databases MEDLINE, EMBASE, and The Cochrane Library. To show an overview of various outcomes by treatment group we conducted a meta-analysis on overall survival. We evaluated whether studies reported statistically significant factors for improved survival.

Results

26 non-randomized controlled trials (7,955 patients enrolled from 1970 to 2001) were identified. We did not identify any RCTs. Risk of bias was high except in 4 studies. Young age and recent year of treatment were identified as factors for improved survival in the HSCT group. Advanced age, SAA without very severe aplastic anemia, and combination of anti-lymphocyte globulin with cyclosporine A were factors for improved survival in the IST group. In 19 studies (4,855 patients), summary statistics were sufficient to be included in meta-analysis. Considerable heterogeneity did not justify a pooled estimate. Adverse events were inconsistently reported and varied significantly across studies.

Conclusions

Young age and recent year of treatment were identified as factors for improved survival in the transplant group. Advanced age, SAA without very severe aplastic anemia, and combination of anti-lymphocyte globulin with cyclosporine A were factors for improved survival in the immunosuppressive group. Considerable heterogeneity of non-randomized controlled studies did not justify a pooled estimate. Adverse events were inconsistently reported and varied significantly across studies.

Allogeneic hematopoietic stem cell transplantation for childhood aplastic anemia: prospective trial in China

We aim to investigate the efficacy and safety of the treatment with fully matched allogeneic hematopoietic stem cell transplants for children with severe aplastic anemia (SAA) in the first prospective trial in China. Six SAA children received allogeneic hematopoietic stem cell transplantation combined with chemotherapy. Five patients had successful engraftment while the sixth child regained normal peripheral blood counts consistent with spontaneous autologous hematopoiesis. Mean duration of follow-up was 2.75 years, and survival was 83%(5/6). The results indicated that allogeneic hematopoietic stem cell transplantation is a good option for the treatment of children with severe aplastic anemia.

Pediatric Bone Marrow Interpretation

The evaluation of pediatric bone marrow poses specific challenges when compared with the general adult population. These challenges stem in part from the higher likelihood of congenital disorders with hematopoietic manifestations, some of which may give rise to hematologic malignancies. Familiarity with the spectrum of disorders seen in the pediatric age group allows for an appropriate and focused differential diagnosis. This review addresses the diagnostic workup of pediatric bone marrow samples, as directed by the peripheral blood and bone marrow findings in the context of the patient's clinical history. Recommendations for the appropriate use of ancillary studies in various scenarios are provided.