Guidelines for the diagnosis and management of acquired aplastic anaemia

The ratio of bone marrow myeloid progenitor cell proportion to mature lymphocytes proportion can effectively differentiate aplastic anemia and hypoplastic myelodysplastic syndrome and evaluate the quality of bone marrow aspirates

INTRODUCTION

Aplastic anemia (AA) and hypoplastic myelodysplastic syndrome (MDS-h) are bone marrow failure disease and difficult to distinguish merely by morphological analysis. In this study, we investigated the value of flow cytometry (FCM) in the differential diagnosis of AA and MDS-h.

METHODS

We included 822 patients (626 control, 69 AA, 22 MDS-h and 105 dilution patients) from January 2017 to December 2022 for a retrospective study. Bone marrow myeloid progenitor (MP) cell and mature lymphocytes proportions were analyzed by FCM. The ratio of MP cell proportion and mature lymphocytes proportion, MPLR, was calculated. Data were compared by Kruskal-Wallis test. Differential diagnostic efficacy was evaluated by receiver operating characteristic (ROC) curve. Cutoff value was determined by the maximum Youden index.

RESULTS

Bone marrow MP cell proportion and MPLR of MDS-h patients were higher than AA patients. Mature lymphocytes proportion of MDS-h patients was lower than AA patients. Area under ROC curve (AUC of ROC) of MP cell proportion, MPLR and mature lymphocytes proportion to distinguish AA from MDS-h were 0.992, 0.988, and 0.850, respectively. Moreover, MPLR of dilution patients was higher than AA patients but lower than MDS-h patients. The AUC of ROC curves of MPLR to distinguish MDS-h and AA from dilution were 0.854 and 0.871, respectively.

CONCLUSION

Bone marrow MP cell proportion and MPLR can effectively discriminate AA from MDS-h with similar differential efficacy, which is higher than mature lymphocytes proportion. Moreover, MPLR can evaluate the quality of bone marrow aspirates, which would interfere with the differential diagnosis.

Upfront Umbilical Cord Blood Transplantation Versus Immunosuppressive Therapy for Pediatric Patients With Idiopathic Severe Aplastic Anemia

Umbilical cord blood transplantation (UCBT) has been rarely reported as a first-line treatment for idiopathic severe aplastic anemia (SAA) patients lacking HLA-matched sibling donors (MSD). Our study aimed to compare the clinical outcomes of pediatric SAA patients who received UCBT and immunosuppressive therapy (IST) upfront. A retrospective analysis was performed on 43 consecutive patients who received frontline IST (n = 17) or UCBT (n = 26) between July 2017 and April 2022. The 3-year overall survival (OS) was comparable between the UCBT and IST groups (96.2% versus 100%, P = .419), while the 3-year event-free survival (EFS) was significantly better in the former than in the latter (88.5% versus 58.8%, P = .048). In the UCBT group, 24 patients achieved successful engraftment, 2 patients developed severe acute graft-versus-host disease (aGVHD), no extensive chronic GVHD (cGVHD), and a high GVHD-free, failure-free survival (GFFS) of 84.6% at 3 years. After 1 year of treatment, 12 patients in the IST group responded, while 5 patients did not achieve remission and 2 patients had disease relapse. At both 3 and 6 months after treatment, the proportion of transfusion-independent patients was higher in the UCBT group than in the IST group. Faster immune recovery and earlier transfusion independence further reduced the risk of infection and bleeding, thereby improving health-related quality of life in the UCBT-treated group. Our results suggested that UCBT as upfront therapy may be an effective and safe option for pediatric SAA patients, with favorable outcomes in experienced centers.

Busulfan for Allogeneic Hematopoietic Stem Cell Transplantation in Children with Severe Aplastic Anemia: A Retrospective Study

INTRODUCTION

This retrospective study aimed to compare a range of conditioning regimens in children with severe aplastic anemia (SAA) undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) at the Seventh Medical Center of PLA General Hospital between January 2008 and June 2017.

METHODS

Patients were categorized into the Bu (Bu + Flu + Cy + ATG-F regimen) and control (Flu + Cy + ATG-F) groups, with a median follow-up time after HSCT of 3.5 (range, 3.1-6.2) and 3.7 (3.2-5.9) years in the Bu and control groups, respectively.

RESULTS

No differences were observed between the two groups regarding the median time of peripheral blood neutrophil and platelet engraftment (p = 0.538 and p = 0.491); the 28-day engraftment rates of neutrophils were similar (p = 0.199), although higher for platelets with Bu (p = 0.044). Additionally, graft failure was 0% and 20.0% in the Bu and control groups, respectively (p = 0.004). In both groups, the incidence of grades III-IV (or grades II-IV) acute graft-versus-host disease (GVHD) and chronic GVHD was not significantly different (p > 0.05). Moreover, the 3-year overall survival and failure-free survival did not show significant differences (p = 0.670 and p = 0.908).

DISCUSSION

In children with SAA undergoing allo-HSCT, conditioning regimen with Bu + Flu + Cy + ATG-F is capable of enhancing the myeloablation effect, promoting donor hematopoietic stem cell engraftment, and reducing the graft failure rate. Furthermore, it does not increase the incidence of complications, including GVHD.

2-DG Re-Normalized IFN-γ Production in T Cells Excluding TEMRA Cells from Patients with Aplastic Anemia

Aplastic anemia (AA) is a T cell immune mediated autoimmune disease in which cytokines, particularly IFN-γ are pathogenesis factors. Glucose metabolism is closely related to effector functions of activated T cells, such as IFN-γ production. The characteristics of glucose metabolism and whether interfering with glucose metabolism could affect T cells produce IFN-γ ability in AA patients remains unknown. In this study, we examined the characteristics of glucose metabolism in T cells from AA patients and the effects of the glucose metabolism inhibitor 2-deoxy-D-glucose (2-DG) on the ability of T cell production IFN-γ. Our data demonstrated abnormal glucose metabolism in stimulated T cells from AA patients, mainly reflected by increased glucose uptake and lactate secretion. In addition, EM and T_EMRA cells exhibit higher glucose uptake in patients with AA compared with healthy individuals. Moreover, the frequency of IFN-γ⁺ was reduced by 2-DG in T cell from AA patients. Unexpectedly, 2-DG re-normalized the frequency of IFN-γ⁺ in other T cell subsets, except for in the T_EMRA. In conclusion, our study reveals for the first time the existence of enhanced aerobic glycolysis in T cells from AA patients, and different T cell subsets exhibit different extent glucose uptake requirements. Aerobic glycolysis regulation may be a potential therapeutic strategy for aberrant T cell immunity. Moreover, T_EMRA may have specific metabolic abnormalities, which should receive more attention in future targeted immune metabolism research.

Increased IFN-γ+ and TNF-α+ mucosal-associated invariant T cells in patients with aplastic anemia

BACKGROUND

Aplastic anemia (AA) is known as an autoimmune disease in which T cell activation is aberrant. It has been reported that unconventional T cells, mucosal-associated invariant T (MAIT) cells, play an important role in several autoimmune diseases, but it is unclear if they are involved in AA.

METHODS

In this study, we for the first time analyzed the proportions, phenotypes, and cytokine properties of MAIT cells in AA by flow cytometry.

RESULTS

We found that the percentage of circulating MAIT cells was generally higher for CD3⁺ , CD8⁺ , and CD8^- T cells in AA patients compared with healthy individuals. Moreover, the percentage of IL-18Rα-, NKG2D-, IFN-γ-, and TNF-α- positive MAIT cells was also significantly higher in AA patients. In addition, the percentage of IFN-γ⁺ CD3⁺ or TNF-α⁺ CD8^- MAIT cells had a significant negative correlation with the absolute neutrophil count.

CONCLUSIONS

We present the first observation of MAIT cells in patients with AA. MAIT cells are associated with a higher frequency of IFN-γ and TNF-α production and may contribute to the pathogenesis of AA.

Antihuman T lymphocyte porcine immunoglobulin combined with cyclosporine as first-line immunosuppressive therapy for severe aplastic anemia in China: a large single-center, 10-year retrospective study

Background

Antihuman T lymphocyte porcine immunoglobulin (p-ATG) has been the most common ATG preparation in immunosuppressive therapy (IST) in Chinese patients with severe aplastic anemia (SAA) since 2009.

Objectives

This study aimed to evaluate the early hematologic response and long-term outcomes of a large cohort of patients with SAA who received p-ATG plus cyclosporine (CsA) as first-line therapy from 2010 to 2019.

Design

This is a single-center retrospective study of medical records.

Methods

We analyzed the data of 1023 consecutive patients with acquired aplastic anemia (AA) who underwent p-ATG combined with CsA as a first-line IST treatment from 2010 to 2019 at our department.

Results

The median age of the patients was 24 (4-75) years, and the median follow-up time was 57.2 months (3 days-137.5 months). There was an early mortality rate of 2.8% with a median death time of 0.9 months (3 days-2.9 months). The overall response rates were 40.6% and 56.1% at 3 and 6 months, respectively. The 5-year cumulative incidences of relapse and clonal evolution were 9.0% [95% confidence interval (CI) = 4.2-16.0%] and 4.5% (95% CI = 1.4-10.6%), respectively. The 5-year overall survival (OS) and event-free survival rates were 83.7% (95% CI = 81.1-86.0%) and 50.4% (95% CI = 47.1-53.5%), respectively.

Conclusion

p-ATG combined with CsA for the treatment of AA is effective and safe, and p-ATG can be used as an alternative ATG preparation for the standard IST regimen in areas in which h-ATG is not available.

Comparable clinical outcomes of haploidentical hematopoietic stem cell transplantation in patients with hepatitis-associated aplastic anemia and non-hepatitis-associated aplastic anemia

Hepatitis-associated aplastic anemia (HAAA), a rare subtype of aplastic anemia (AA), is defined as bone marrow failure occurring after acute hepatitis. Severe HAAA requires immunosuppressive therapy (IST) or hematopoietic stem cell transplantation (HSCT) as lifesaving treatment. The outcomes of HAAA patients who underwent haploidentical hematopoietic stem cell transplantation (haplo-HSCT) have not been systematically evaluated. We retrospectively compared the characteristics of 15 patients with HAAA and 60 non-hepatitis-associated aplastic anemia (non-HAAA) patients, all 75 of whom underwent haplo-HSCT in our hospital between January 2006 and October 2021. The median ages of the patients were 18 years old (range, 3-36) for HAAA patients and 13 years (range, 2-45) for non-HAAA patients (p = 0.693). The median time for neutrophil engraftment was 14 days (range, 11-22) in the HAAA group and 12 days (range, 10-21) in the non-HAAA group (p = 0.363). At the time of analysis, 15 HAAA patients and 58 non-HAAA patients were alive, and their median follow-up times were 37 (range, 3-87) months and 31 (range, 2-110) months (p = 0.347), respectively. There were no significant differences in the three-year overall survival (OS) rates (100% vs. 96.7 ± 0.33%, P = 0.638) or liver event-free survival (LEFS) (80.0 ± 0.17% vs. 76.7 ± 0.19%, P = 0.747) between the two groups. Despite the small number of HAAA patients due to the rarity of the disease, these results, such as the similar incidence rates of 3-year OS and fewer liver events than expected, suggest that haplo-HSCT is a feasible treatment for HAAA a when there are no human leukocyte antigen (HLA)-matched donors available and has a low risk of transplant-related mortality and complications.

Effects of cimetidine on ciclosporin population pharmacokinetics and initial dose optimization in aplastic anemia patients

The present study aimed to explore the effects of cimetidine on ciclosporin population pharmacokinetics and initial dose optimization in aplastic anemia patients. Aplastic anemia patients were used to establish a population pharmacokinetic model by the nonlinear mixed effect (NONMEM), and concentrations of ciclosporin were simulated by Monte Carlo method. With the same weight, the ciclosporin clearance rates were 0.387:1 in patients with or without cimetidine, respectively. In the measured ciclosporin concentrations, compared to aplastic anemia patients without cimetidine, ciclosporin concentrations were higher in patients with cimetidine (P < 0.01). Further research found that at the same body weight and same dose, ciclosporin concentrations in aplastic anemia patients with cimetidine were indeed higher than those in patients without cimetidine (P < 0.01). The initial recommended ciclosporin dose for patients without cimetidine were 7mg/kg splited into two doses for weight of 40-60kg, and 6mg/kg splited into two doses for weight of 60-100kg. The patients with cimetidine were recommended to take 3mg/kg ciclosporin splited into two doses for weight of 40-100kg. It was the first time to explore the effects of cimetidine on ciclosporin population pharmacokinetics and initial dose optimization in aplastic anemia patients. Patients coadministration of cimetidine, may need low ciclosporin dose.

Treatment outcome of 301 aplastic anemia patients in China: a 10-year follow-up and real-world data from single institute experience

OBJECTIVE

This study was carried out to explore clinical treatment and prognosis of patients with AA with different economic status. Methods: We retrospectively analyzed the clinical outcome of 301 patients with AA in our center from April 2008 to November 2017.

RESULTS

Treatments included anti-thymocyte globulin (ATG) or anti-lymphocyte globulin (ALG) combined with cyclosporineA (CsA) (9%), allogeneic hematopoietic stem cell transplantation (allo-HSCT) (7%), CsA combined with androgen or CsA alone (hereinafter referred to as CsA group) (77%), no specific therapy (7%). The 5-year overall survival (OS) was higher in patients with non-severe AA (94.6%) compared with those with severe AA (SAA) (66.6%, P <.001), very severe AA (VSAA) (41.3%, P <.001). The 5-year OS was 76.5% in patients with SAA/VSAA treated with ATG/ALG combined with CsA, 75% in allo-HSCT group(P =.936), 63.6% in CsA group (P =.557), which was significantly higher than no specific therapy group (21.8%, P =.002). For those who responded to CsA , the duration of CsA (median follow-up time: 27 months, 1-101 months) was positively correlated with progression-free survival (r=0.603, P <.001). Multivariate analysis revealed that 36-65 years of age, SAA/VSAA, and no specific therapy were independent risk factors for inferior survival.

CONCLUSION

The treatment of elderly patients with AA still faces challenges. CsA is benefit to the survival of SAA/VSAA patients. AA patients, who responded to initialy CsA treatment, may benefit from prolonged CsA treatment. In view of the side effects of CsA, the timing of withdrawal is worth further exploration.

Upregulated Expression of Profilin1 on Dendritic Cells in Patients With Severe Aplastic Anemia

Severe aplastic anemia (SAA) is a life-threatening form of bone marrow failure that is associated with very high mortality. Dendritic cells (DCs) are antigen presenting cells (APCs) with powerful movement ability, which is an important factor affecting immune function. The expression of profilin1 (Pfn1) plays an important role in the regulation of cell movement ability. We detected the expression of Pfn1 mRNA in the bone marrow (BM) myeloid dendritic cells (mDCs) from patients with SAA using RT-PCR. Next, we examined Pfn1 expression on mDCs using flow cytometry (FCM). We also assessed the relationship between Pfn1 expression and cytokine levels. Our data showed increased Pfn1 mRNA expression in patients with SAA. The expression of Pfn1 in BM mDCs increased in SAA patients. The expression of Pfn1 on mDCs and cytokines (TNF-α and IFN-γ) were positively correlated in the serum of untreated patients with SAA. Taken together, we found that the expression of Pfn1 on mDCs of SAA patients increased, which may affect the function of mDCs. Profilin 1 may be involved in the immunopathogenesis of SAA.

Evolving Role of Pharmacogenetic Biomarkers to Predict Drug-Induced Hematological Disorders

ABSTRACT

Drug-induced hematological disorders constitute up to 30% of all blood dyscrasias seen in the clinic. Hematologic toxicity from drugs may range from life-threatening marrow aplasia, agranulocytosis, hemolysis, thrombosis to mild leukopenia, and thrombocytopenia. Pathophysiologic mechanisms underlying these disorders vary from an extension of the pharmacological effect of the drug to idiosyncratic and immune-mediated reactions. Predicting these reactions is often difficult, and this makes clinical decision-making challenging. Evidence supporting the role of pharmacogenomics in the management of these disorders in clinical practice is rapidly evolving. Despite the Clinical Pharmacology Implementation Consortium and Pharmacogenomics Knowledge Base recommendations, few tests have been incorporated into routine practice. This review aims to provide a comprehensive summary of the various drugs which are implicated for the hematological adverse events, their underlying mechanisms, and the current evidence and practical recommendations to incorporate pharmacogenomic testing in clinical care for predicting these disorders.

Pregnancy in Classical Paroxysmal Nocturnal Hemoglobinuria and Aplastic Anemia-Paroxysmal Nocturnal Hemoglobinuria: A High-Risk Constellation

Pregnancies in paroxysmal nocturnal hemoglobinuria (PNH) are associated with increased morbidity and mortality. Retrospective studies suggest that outcome has improved with the advent of the complement inhibitor eculizumab. To substantiate this assumption we analyzed the data from patients treated in our department since 2009. All patients were included in the International PNH registry and followed prospectively. We identified 16 pregnancies in 9 patients with classical PNH, and two pregnancies in two patients with aplastic anemia (AA)-PNH. In classical PNH, 13 pregnancies were supported by eculizumab. Breakthrough hemolysis occurred in six pregnancies, necessitating an increase in the biweekly eculizumab dose from 900 mg to 1,200–1,800 mg. Red blood cell transfusions were given in six and platelet transfusions in two pregnancies. A Budd-Chiari syndrome and cholecystitis complicated the course of two pregnancies. Four of 13 pregnancies supported by eculizumab ended in spontaneous abortion or stillbirth, and one was prematurely terminated because of fetal trisomy 21. None of the three pregnancies not supported by eculizumab had a successful outcome. Half the deliveries were preterm. None of the patients died, and, in all but one patient, the post-partum period was uneventful. Both pregnancies in patients with AA-PNH took a favorable course. Our results confirm low maternal mortality and frequent breakthrough hemolysis in pregnant PNH patients receiving eculizumab. Fetal mortality and the rate of preterm delivery were higher than reported previously, possibly related to the use of registry data that are likely to reduce the risk of publication and recall biases.

Multivariate logistic analysis of predictors of response to immunosuppressive therapy in children with aplastic anemia: a double-center study

BACKGROUND

Immunosuppressive therapy (IST) composed of antithymocyte globulin (ATG) and cyclosporine A (CSA) is one of the standard therapies in pediatric patients with acquired aplastic anemia (AA), but predictors of IST are lack of consensus.

PROCEDURES

Ninety-four patients from two pediatric medical centers in China were included between January 2005 and March 2018. Clinical factors associated with the efficacy were analyzed according to multivariate logistic regression model previously established.

RESULTS

We discovered that overall responsiveness was 77.66%. Five out of 35 factors were statistically significant in univariate analysis. Based on the cutoff point chosen by receiver operating characteristic (ROC) curve, 5 continuous variables were made categorical, among which 3 variables with significance were employed to establish the logistic regression equation. Based on these 3 variables, we found that starting IST within 126 days of the first appearance of symptoms (X1, p = .003), absolute neutrophil count (ANC) higher than 0.435×10⁹/L (X2, p = .012), and rate of decreased actual lymphocyte count (ALC) higher than 59.2% within the 1st week after IST (X3, p = .001) were three independent risk factors for response to IST. The rate of decreased ALC higher than 59.2% after IST was the most significant variable (OR = 9.355, Log (P) = -2.161 + 2.149X1 + 1.662X2 + 2.236X3). The accuracy, sensitivity, and specificity of the model were 86.2%, 94.5% and 57.1%, respectively.

CONCLUSION

Duration of AA, ANC and decreased ALC rate after IST might predict the response to IST, among which the rate of decreased ALC after IST is the most important predictive factor.

Idiopathic Aplastic Anemia: An Update

"Bone marrow failure" encompass all the conditions and syndromes in which there are qualitative or quantitative disorders of one or more lineages (erythroid, myelomonocytic, and/or megakaryocytic). A few years ago, the pathophysiology of these syndromes was completely unknown. Today we have better knowledge for these diseases, allowing the development of new treatment options and the improvement of patients' outcome. Acquired bone marrow failure syndromes include myelodysplastic syndromes, aplastic anemia, paroxysmal nocturnal hemoglobinuria, idiopathic neutropenia and large granular leukemia. All these syndromes share some common features and pathophysiology. The most important feature is the possibility of clonal evolution and progression into acute myelogenous leukemia, and open questions still remain on how to prevent evolution in these patients.

Cyclosporine Therapy in Patients with Transfusion-independent Non-severe Aplastic Anemia: A Retrospective Analysis

Objective The therapeutic approach for transfusion-independent non-severe aplastic anemia (NSAA) is undetermined. This study aimed to investigate the efficacy of immunosuppressive therapy (IST) for NSAA. Methods We retrospectively reviewed 42 consecutive patients with transfusion-independent NSAA. NSAA was further divided into two stages according to the degree of cytopenia. Progression was defined as transition to a transfusion-dependent state. Results Twelve (29%) patients received IST with cyclosporine A (CsA). Eleven (26%) patients became transfusion-dependent. In all patients, a univariate analysis revealed that a low hemoglobin level (p=0.006) and low reticulocyte count (p=0.005) were associated with a high probability of progression. The estimated transfusion-free survival (TFS) was significantly prolonged by IST among patients with advanced-stage NSAA (p=0.002), while IST did not reduce the incidence of progression in the overall cohort (p=0.349). In the non-IST group, an advanced clinical stage was significantly associated with progression (p=0.003). In contrast, the clinical stage was not related to progression in the IST group (p=0.318). None of the patients had to discontinue treatment with CsA due to renal failure. Conclusion IST is expected to be effective in patients with advanced-stage NSAA.

Associations between the HLA-A/B/DRB1 polymorphisms and aplastic anemia: evidence from 17 case-control studies

OBJECTIVE

To estimate the associations between HLA-A/B/DRB1 polymorphisms and aplastic anemia (AA), we carried out the meta-analysis.

METHODS

In this meta-analysis, all publications in English and Chinese were considered up to 30 September 2015. The electronic databases we searched were Pubmed, Science Direct, Embase, Web of Science, CNKI, Wanfang Data and VIP. We conducted all statistical data analyses in the Stata11.0 software.

RESULTS

A total of 17 studies including 9164 subjects (containing 1372 cases and 7792 controls) were retrieved, which studied the relationship between HLA-A/B/DRB1 and AA. Odds ratios (ORs) with 95% confidence intervals (CIs) for the comparisons between cases and controls were calculated. The result revealed that HLA-A*02 and HLA-DRB1 (*0407, *15 and *1501) polymorphisms might increase the risk of AA. Otherwise, HLA-DRB1 (*0301, *04, *0406, *0802, *1301, *1302 and *14) were protective against AA. But, other sites of HLA-A/B/DRB1 in our study had no correlations with AA (all P_c > 0.05).

CONCLUSION

In conclusion, HLA-A/B/DRB1 polymorphisms may play an important role in AA, but higher quality and larger sample studies are needed to confirm.

Incidence and outcome of acquired aplastic anemia: real-world data from patients diagnosed in Sweden from 2000-2011

A plastic anemia is a rare life-threatening disease. However, since the introduction of immunosuppressive therapy and allogeneic stem cell transplantation, the outcome has improved considerably, and the 5-year survival is reported to be 70–80% in selected patient cohorts. Yet, contemporary population-based data on incidence and survival are lacking. We performed a national retrospective study to determine the incidence, treatment, and survival of patients with aplastic anemia diagnosed in Sweden from 2000–2011. Patients were included via the National Patient Registry, and diagnosed according to the Camitta criteria. In total, 257 confirmed cases were identified, with an overall incidence of 2.35 (95% CI: 2.06–2.64) cases per million inhabitants per year. Median age was 60 years (range: 2–92), and median follow up was 76 (0–193) months. Primary treatments included immunosuppressive therapy (63%), allogenic stem cell transplantation (10%), or single-agent cyclosporine/no specific therapy (27%). The 5-year survival was 90.7% in patients aged 0–18 years, 90.5% in patients aged 19–39 years, 70.7% in patients aged 40–59 years, and 38.1% in patients aged ≥60 years. Multivariate analysis showed that age (both 40–59 and ≥60 age groups), very severe aplastic anemia and single-agent cyclosporine/no specific therapy were independent risk factors for inferior survival. In conclusion, younger aplastic anemia patients experience a very good long-term survival, while that of patients ≥60 years in particular remains poor. Apparently, the challenge today is to improve the management of older aplastic anemia patients, and prospective studies to address this medical need are warranted.

A Review of Myeloablative vs Reduced Intensity/Non-Myeloablative Regimens in Allogeneic Hematopoietic Stem Cell Transplantations

Allogeneic hematopoietic stem cell transplantation (Allo-HSCT) is a curative treatment option for both malignant and some benign hematological diseases. During the last decade, many of the newer high-dose regimens in different intensity have been developed specifically for patients with hematologic malignancies and solid tumors. Today there are three main approaches used prior to allogeneic transplantation: Myeloablative (MA), Reduced Intensity Conditioning (RIC) and Non-MA (NMA) regimens. MA regimens cause irreversible cytopenia and there is a requirement for stem cell support. Patients who receive NMA regimen have minimal cytopenia and this type of regimen can be given without stem cell support. RIC regimens do not fit the criteria of MA and NMA: the cytopenia is reversible and the stem cell support is necessary. NMA/RIC for Allo-HSCT has opened a new era for treating elderly patients and those with comorbidities. The RIC conditioning was used for 40% of all Allo-HSCT and this trend continue to increase. In this paper, we will review these regimens in the setting of especially allogeneic HSCT and our aim is to describe the history, features and impact of these conditioning regimens on specific diseases.

Diagnostic value of platelet indices and bone marrow megakaryocytic parameters in immune thrombocytopenic purpura

Platelet indices could mirror megakaryopoietic activity in immune thrombocytopenic purpura (ITP), but its specificity and sensitivity need to be studied. The diagnostic performance of platelet indices was analyzed by receiver-operating characteristic curves, and the probability of true positive (sensitivity) and true negative (specificity) in predicting ITP, myelodysplasia, or controls was determined. Mean platelet volume (MPV) was higher, whereas plateletcrit (PCT) was significantly lower in ITP than in myelodysplasia and controls. The platelet distribution width in ITP patients was lower than in myelodysplasia, but higher than in controls. Increased megakaryocytes were only observed in ITP. A strong positive correlation was found between MPV and quantities of granular megakaryocytes, whereas a negative relationship existed between MPV and platelet-form megakaryocytes. In receiver-operating characteristic analysis, MPV and PCT gave a sensitivity of 70.3% (89.8%) and specificity of 74.8% (84.7%) at a cutoff of 9.35 (0.085) in diagnosis of ITP. Combined parallel test of MPV and PCT increased the sensitivity to 97.5 with 64.1% specificity, whereas series test increased the specificity to 94.7 with 62.7% sensitivity. Our results suggest that MPV, PCT, and platelet distribution width represent megakaryopoietic activity in bone marrow and may be reliable markers in ITP diagnosis.

Immunosuppressive therapy versus alternative donor hematopoietic stem cell transplantation for children with severe aplastic anemia who lack an HLA-matched familial donor

We compared the outcomes of immunosuppressive treatment (IST) with those of alternative donor hematopoietic stem cell transplantation (HSCT) in children and adolescents with severe aplastic anemia (SAA). The medical records of 42 patients with SAA who received frontline IST (N=19) or frontline HSCT with an alternative donor (N=23) between 1998 and 2012 were analyzed retrospectively. Six patients responded in the frontline IST group, whereas 11 underwent salvage HSCT after IST failure. Twenty-one of 23 patients who underwent frontline HSCT survived without treatment failure. The estimated failure-free survival rate of the frontline HSCT group was higher than that of the frontline IST group (91.3% vs 30.7% respectively, P<0.001). Six of 11 patients who underwent salvage HSCT experienced event-free survival (EFS). The estimated EFS of the frontline HSCT group was higher than that of the salvage HSCT group (91.3% vs 50.9% respectively, P=0.015). The outcome of alternative donor HSCT was better than commonly reported rates, especially in patients who underwent frontline HSCT. These results suggest that frontline alternative donor HSCT may be a better treatment option than IST for children and adolescents with SAA who lack a human leukocyte Ag-matched familial donor.

Eltrombopag for the treatment of aplastic anemia: current perspectives

Aplastic anemia (AA) is a potential life-threatening hematopoietic stem cell (HSC) disorder resulting in cytopenia. The mainstays of treatment for AA are definitive therapy to restore HSCs and supportive measures to ameliorate cytopenia-related complications. The standard definitive therapy is HSC transplantation for young and medically fit patients with suitable donors and immunosuppressive therapy (IST) with antithymocyte globulin and cyclosporine for the remaining patients. A significant proportion of patients are refractory to IST or relapse after IST. Various strategies have been explored in these patients, including second course of antithymocyte globulin, high-dose cyclophosphamide, and alemtuzumab. Eltrombopag, a thrombopoietin mimetic, has recently emerged as an encouraging and promising agent for patients with refractory AA. It has demonstrated efficacy in restoring trilineage hematopoiesis, and this positive effect continues after discontinuation of the drug. There are ongoing clinical trials exploring the role of eltrombopag as a first-line therapy in moderate to severe AA and a combination of eltrombopag with IST in severe AA.

Low Vitamin D Levels Are Associated With an Adverse Clinical Outcome in Febrile Neutropenia

AIM

The aim of the study was to evaluate the levels of vitamin D in patients of aplastic anemia presenting with febrile neutropenia and its association with clinically important parameters.

MATERIALS AND METHODS

The 25-hydroxy vitamin D (25(OH)D) levels were measured in 35 patients of aplastic anemia with febrile neutropenia in the age group of 4 to 16 years. About 30 healthy children served as controls. Vitamin D deficiency was defined as 25(OH)D<20 ng/mL, insufficiency 20 to 29 ng/mL, and sufficiency≥30 ng/mL.

RESULTS

The median age of patients was 9.3 years. The mean 25(OH)D level was 17.71±8.90 ng/mL in patients against 23.67±10.80 ng/mL in the control group (P<0.01). About 65.7% of the patients were 25(OH)D deficient (<20 ng/mL). Only 8.6% had sufficient levels. Older (above 10 y) patients, male children, and those from a rural background and a low socioeconomic status had significantly lower 25(OH)D levels as compared with controls. Low 25(OH)D levels were associated with a longer duration (≥7 d) of febrile neutropenia (17.26±7.19 vs. 20.01±12.12 ng/mL) although the difference was not statistically significant. Two patients who expired had significantly lower 25(OH)D levels (12.85±4.12 ng/mL) compared with those who improved (22.86±6.47 ng/mL, P<0.05).

CONCLUSIONS

A high prevalence of vitamin D deficiency was observed in patients with febrile neutropenia. Low levels were associated with an adverse clinical outcome.

Allogeneic hematopoietic stem cell transplantation as the first-line treatment option in a patient with severe aplastic anemia without a matched related donor: A case report

The outcomes of matched unrelated donor (MUD) hematopoietic stem cell transplantation (HSCT) and immunosuppressive therapy (IST) in patients with severe aplastic anemia (SAA) remain controversial. The clinical outcome in patients that undergo transplantation following failed IST is typically poorer when compared with patients that initially underwent transplantation. Clinical treatment algorithms have been proposed to determine the management of such patients, and account for individual conditions, personal preferences and prognostic risk factors. The present study reports the promising outcome of a 22-year-old patient exhibiting SAA. The patient underwent peripheral blood stem cell transplantation (PBSCT) from an MUD using a fludarabine-based conditioning regimen and low-dose total body irradiation as an alternative method to first-line IST. The patient achieved rapid bone marrow reconstitution and has been in complete remission for 32 months. The aim of the fludarabine-based conditioning regimen with PBSCT was to improve the patient’s therapeutic outcome and provide a convenient treatment strategy. Furthermore, this regimen extends the application of HSCT to patients who are older or those that are without a matched related donor.

Recent Developments in Drug Therapy for Aplastic Anemia

Objective: This article reviews recent developments in immunosuppressive therapy (IST) for aplastic anemia (AA) patients who are not candidates for stem cell transplant (SCT); including, front-line, salvage, and novel treatment options with a focus on response rates (RRs) and overall survival (OS). Data Sources: A PubMed literature search was performed from 1977 to June 2014 using the search terms aplastic anemia, horse antithymocyte globulin (hATG), rabbit ATG (rATG), thymoglobulin, and cyclosporine (CSA). Additional references were identified from a review of literature citations. Study Selection and Data Extraction: All English-language studies investigating IST for treatment of AA in non–SCT candidates were evaluated. Data Synthesis: Studies indicate addition of CSA and corticosteroids to hATG for treatment of AA improves RRs, decreases relapse rates, and improves 5-year OS. hATG improved RRs, relapse rates, and OS compared to rATG in the front-line setting. Studies support the use of rATG when front-line IST with hATG fails or when hATG is unavailable. Front-line daclizumab can be considered for nonsevere AA (NAA); however, data is limited. Alemtuzumab or eltrombopag are options for relapsed AA in select patients. Conclusions: hATG with methylprednisolone and CSA is recommended for front-line treatment of AA, whereas rATG is reserved for salvage therapy. Front-line use of daclizumab has been studied in NAA patients, but additional prospective trials are needed before this is adopted into clinical practice. Alemtuzumab and eltrombopag have been studied for treatment of AA; recruiting is ongoing in clinical trials to assess the appropriate dosing strategy and place in therapy.

Association of severe thrombocytopenia and poor prognosis in pregnancies with aplastic anemia

Purpose

We sought to estimate the risks of adverse obstetric outcomes and disease outcomes associated with severe thrombocytopenia in pregnant women with aplastic anemia (AA).

Methods

In a retrospective study, we compared demographics, clinical characteristics, laboratory results, and outcomes between severe thrombocytopenia (ST) and non-severe thrombocytopenia (non-ST) groups comprising pregnant women with AA.

Results

Of 61 AA patients, 43 (70%) were diagnosed as AA before pregnancy and 18 (30%) were AA during pregnancy. The ST group exhibited lower gestational age at nadir of platelet count (26.0 versus 37.0 weeks, p<0.001) and at delivery (37.3 versus 39.1 weeks, p = 0.008), and a higher rate of bleeding gums (33.8 versus 7.7%, p = 0.015) than the non-ST group. In addition, the ST group exhibited more transfusions during pregnancy (72.7 versus 15.4%, p<0.001) and postpartum period (45.0 versus 2.7%, p<0.001), and more bone marrow transplant after delivery (25.0 versus 0.0%, p<0.001) than the non-ST group. The ST group had a higher odds ratio of composite disease complications (OR, 9.63; 95% CI, 2.82–32.9; p<0.001) and composite obstetric complications (OR, 6.78; 95% CI, 2.11–21.8; p = 0.001) than the non-ST group.

Conclusions

Severe thrombocytopenia is more associated with obstetric and disease complications than is non-severe thrombocytopenia in pregnant women with AA.

Outcomes of hematopoietic cell transplantation in adult patients with acquired aplastic anemia using intermediate-dose alemtuzumab-based conditioning

Graft-versus-host disease (GVHD) has no therapeutic benefit after hematopoietic cell transplantation (HCT) for patients with acquired aplastic anemia (AA), and its prevention is highly desirable. We designed a conditioning regimen using an intermediate dose of alemtuzumab (50 to 60 mg) and describe our institutional experience of 41 patients who underwent HCT for AA. The median age at HCT was 37 years (range, 17 to 59). The conditioning regimen was high-dose cyclophosphamide (n = 9) or fludarabine based (n = 32). Additional GVHD prophylaxis was with cyclosporine. With a median follow-up of 3.6 years, overall survival at 3 years was 85%. Survival in patients <40 years and ≥40 years was 96% and 67%, respectively (P = .04). Graft failure occurred in 4 (10%) patients; 2 primary and 2 secondary. The cumulative incidences of acute (grades 1 to 2) and chronic GVHD were 27% and 15%, respectively. No patients developed grade 3 to 4 acute GVHD or severe chronic GVHD. The following viral complications were frequent: cytomegalovirus reactivation (79%), herpes simplex (18%), varicella zoster (25%), and BK virus hemorrhagic cystitis (8%). The majority of patients had no significant long-term health issues. This intermediate-dose alemtuzumab-based conditioning regimen results in excellent survival with a favorable impact on GVHD and long-term health outcomes, but close monitoring for viral complications is important.

Hematopoetic stem cell transplantation in children

Bone marrow transplantation is called hematopoetic stem cell transplantation (HSCT), since peripheral blood and umbilical cord blood can also be used as sources of stem cell currently. In children, bone marrow transplantation is used as a definite treatment method in many diseases including hemoglobinopaties, immune deficiencies, bone marrow failure and congenital metabolic diseases in addition to hematological malignancies. In addition to the underlying disease, the most important factors which have an impact on prognosis include infections which develop during the process of transplantation and graft-versus-host disease. In this article, it was aimed to give brief information on stem cell sources, preparation therapies, HSCT indications and post-transplantation complications in children.

Evaluation of danazol, cyclosporine, and prednisolone as single agent or in combination for paroxysmal nocturnal hemoglobinuria

Objective: The responses of 32 patients with paroxysmal nocturnal hemoglobinuria (PNH) were assessed after the patients were put on various combinations of danazol, prednisolone, and cyclosporine.

Materials and Methods: Nineteen males and 13 females aged between 14 and 60 years with confirmed diagnosis of PNH were treated with danazol (4), danazol + cyclosporine (7), cyclosporine (1), and prednisolone + danazol (20). Response to these interventions was assessed regularly. Danazol was added to cyclosporine in patients with aplastic bone marrow after 3 months of cyclocporine use only unless the former therapy was successful. Four patients with aplastic marrow received only danazol because they had renal insufficiency at presentation. Patients were evaluated with regular complete blood count and routine liver and renal function tests.

Results: One patient responded to cyclosporine only. Thirteen of 32 patients (40%) had complete response, 12/32 patients (37%) had partial response leading to freedom from red cell transfusion, and 2/32 (7%) had no response. Five patients (16%) died due to thrombosis or hemorrhage within 3 months of therapy before their response to therapy could be assessed. The median period of review of the cases was 4 years and 6 months.

Conclusion: Danazol is a useful addition to PNH therapy both in combination with cyclosporine for hypoplastic PNH and with prednisolone for other forms of PNH, and this therapy could be a good alternative where eculizumab and anti-lymphocyte globulin cannot be used for various reasons.

Conflict of interest:None declared.

Epidemiological Features of Aplastic Anemia in Indian Children

OBJECTIVES

To study the socio-demographic profile and clinico-hematological features of aplastic anemia in children presenting at a single institution over 5 y.

METHODS

Patients below the age of 15 y presenting with features of aplastic anemia were included in the study. Epidemiology, clinico-hematological features and treatment received were recorded in all the cases. Serology for hepatitis A, B, C, E, EBV, parvovirus and HIV was carried out. Cytogenetic studies were available in approximately half of the patients.

RESULTS

One hundred eighty five patients were diagnosed with aplastic anemia. Ten patients with inherited bone marrow failure syndrome (IBMFS) were excluded. Median age was 8 y (range 4-14 y) with a male to female ratio of 2.4:1. Pallor (100 %) followed by bleeding manifestations (83.8 %) and fever (73.5 %) were most common presenting symptoms. One hundred twenty patients (70 %) were classified as severe, 36 (21 %) very severe and 17 (9 %) non-severe aplastic anemia. Viral markers for parvovirus, Epstein barr virus and hepatitis were positive in 25.8 %, 20 % and 6.7 % patients respectively. Six patients had history of varicella infection in recent past (within 6 mo). Very few patients (30) could afford immunosuppressive therapy (IST) and had suboptimal response (29.7 %).

CONCLUSIONS

Majority of patients had idiopathic aplastic anemia. Very severe aplastic anemia and severe aplastic anemia were frequent. Few patients received IST and had suboptimal response. There is need to establish a national registry for aplastic anemia.

Outcome of patients activating an unrelated donor search for severe acquired aplastic anemia

Patients with severe aplastic anemia (SAA) without a sibling donor receive immunosuppressive treatment (IST) with anti-thymocyte globulin (ATG). In the case of no response to IST, a voluntary unrelated donor (VUD) search is usually started. This study analyzes the outcome of ATG-refractory SAA patients activating a VUD search. Of 179 patients, 68 had at least one HLA-A, -B, and -DR matched donor identified and underwent HSCT while 50 also with a donor were not transplanted because of early death (8), late response to IST (34), transplant refusal (1), or other (7). Conversely, 61 had no matched donor, 13 of those ultimately received a mismatched HSCT. All but one received marrow stem cells. Among patients aged <17 years, those with at least one matched donor had a significant higher 4-year survival as compared to others (79% ± 6% versus 53% ± 10%, P = 0.01). There was also a survival advantage independent of recipient age when the donor search was initiated in the recent 2000-2005 study-period (74% ± 6% versus 47% ± 10%, P < 0.05). In multivariate analysis, the identification of a matched VUD tended to impact favourably on survival in patients with a recent donor search (P = 0.07). This study provides evidence for the use of unrelated donor HSCT in children and adults with IST-refractory SAA.

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.

Aplastic anemia: a common hematological abnormality among peripheral pancytopenia

Background:

Aplastic anemia is a well-recognized form of marrow failure. The incidence of aplastic anemia is subjected to wide variation. Most cases are acquired and immune-mediated but there are also inherited forms.

Aim:

The study was conducted to assess the magnitude of the problem, morphological changes and determinants of aplastic anemia in North Bengal.

Materials and Methods:

A cross-sectional study had been conducted for a period of one year among 5 to 70 years age group. Initially complete blood count followed by bone marrow examination was done for diagnosis.

Results:

Out of 48 cases, 38 (79.17%) had hypocellular diagnosed as aplastic anemia, 5 (10.42%) each had normocellular and hypercellular bone marrow. Histopathology shows that 30 (78.95%) cases had increased iron stores in bone marrow and 8 (21.05%) cases had decreased iron stores. Subjects less than 20 years of age mostly (31.58%) suffered from non-severe disease in contrast to subjects in higher age groups who had severe or very severe disease, though the trend was not significantly different (χ² for linear trend 0.171, P > 0.05).

Conclusion:

The study shows aplastic anemia is a common hematological abnormality among peripheral pancytopenia in North Bengal region where males were affected more than females.

Assessment of the association between colchicine therapy and serious adverse events

STUDY OBJECTIVE

As data that prompted a 2009 labeling change detailing contraindications, precautions, and dosing recommendations for the first branded colchicine product were limited to case reports of myotoxicity and blood dyscrasias ascribed to the drug, we sought to quantify the association of colchicine therapy with serious adverse outcomes in a cohort of insured patients.

DESIGN

Case-control study.

DATA SOURCE

Kaiser Permanente Colorado electronic data warehouses and electronic medical records.

PATIENTS

Cases were patients with a creatine kinase (CK) level of at least 2000 U/L or who developed a clinically significant non-cancer-related blood dyscrasia (thrombocytopenia, neutropenia, leukopenia, aplastic anemia, or pancytopenia) between January 1, 2006, and June 30, 2009 (954 cases). Each case was matched to up to 10 controls by age, sex, and index date (date of the increased CK level or blood dyscrasia-supporting laboratory value). Controls were patients without elevated CK levels or blood dyscrasias who had a routine health maintenance examination during the same time period (index date was the date of their health maintenance examination [9007 controls]).

MEASUREMENTS AND MAIN RESULTS

The primary study outcome was colchicine exposure, defined as a colchicine prescription purchase in the 100 days before the index date. The likelihood of colchicine exposure was examined with conditional logistic regression. Cases experienced a higher rate of previous colchicine exposure compared with controls (0.6% vs 0.2%, odds ratio 3.9, 95% confidence interval 1.4-10.7). In addition, cases had higher hospitalization rates (14.9% vs 5.0%, p<0.001), higher mean chronic disease scores (2.5 vs 0.0, p<0.001), and were more likely to have been exposed to drugs that may increase the risk of adverse events due to an interaction with a CYP3A4 inhibitor drug (6.9% vs 2.3%, p<0.001).

CONCLUSION

Patients with confirmed elevations in CK level and/or blood dyscrasias had a higher rate of previous colchicine exposure, although low overall, and greater hospitalization rates and exposure to drugs that may increase the risk of adverse events compared with controls. These findings support the 2009 United States Food and Drug Administration labeling for the first branded colchicine product, cautioning use in patients with liver impairment or renal dysfunction and/or those receiving concurrent drugs that may increase risk of adverse events.

Correlations between HLA-A, HLA-B and HLA-DRB1 allele polymorphisms and childhood susceptibility to acquired aplastic anemia

To investigate the correlations between polymorphisms of human leukocyte antigen (HLA)-A, HLA-B and HLA-DRB1 alleles and childhood susceptibility to aplastic anemia (AA), 80 children with AA were investigated. Among the 80 children, 74 had severe AA (SAA). Blood samples were collected from 109 healthy children as the controls. High-resolution genotyping of HLA-A, HLA-B and HLA-DRB1 alleles was conducted using polymerase chain reaction amplification with sequence-specific primers and polymerase chain reaction amplification with sequence-based typing. The expression frequencies of HLA-B*48:01 and DRB1*09:01 were significantly higher and the frequencies of HLA-B*51:01, DRB1*03:01 and DRB1*11:01 were significantly lower in the AA group compared with those in the control group. In addition, the frequencies of HLA-B*48:01 and DRB1*09:01 were significantly higher and the frequencies of HLA-B*51:01, DRB1*03:01 and DRB1*11:01 were significantly lower in the SAA group compared with those in the control group. HLA-B*48:01 and DRB1*09:01 were correlated with childhood AA, and thus they may be susceptibility genes for childhood SAA. HLA-B*51:01, DRB1*03:01 and DRB1*11:01 are expressed at low levels in children with AA.

Mechanisms of alloimmunization and subsequent bone marrow transplantation rejection induced by platelet transfusion in a murine model

For many nonmalignant hematological disorders, HLA-matched bone marrow transplantation (BMT) is curative. However, due to lack of neoplasia, the toxicity of stringent conditioning regimens is difficult to justify, and reduced intensity conditioning is used. Unfortunately, current reduced intensity regimens have high rates of BMT rejection. We have recently reported in a murine model that mHAs on transfused platelet products induce subsequent BMT rejection. Most nonmalignant hematological disorders require transfusion support prior to BMT and the rate of BMT rejection in humans correlates with the number of transfusions given. Herein, we perform a mechanistic analysis of platelet transfusion-induced BMT rejection and report that unlike exposure to alloantigens during transplantation, platelet transfusion primes alloimmunity but does not stimulate full effector function. Subsequent BMT is itself an additional and distinct immunizing event, which does not induce rejection without antecedent priming from transfusion. Both CD4(+) and CD8(+) T cells are required for priming during platelet transfusion, but only CD8(+) T cells are required for BMT rejection. In neither case are antibodies required for rejection to occur.

Diagnosis and treatment of acquired aplastic anaemia in adults: 142 cases from a multicentre, prospective cohort study in Shanghai, China

To improve diagnosis and therapy for aplastic anaemia (AA) in Shanghai, clinical and laboratory data for patients with AA (n = 142) and hypocellular myelodysplastic syndrome (MDS; n = 22) were comparatively analysed (follow-up 2 - 6 years). Red blood cell distribution width and absolute lymphocyte and reticulocyte counts were significantly different between the two groups. AA was diagnosed in 54.2% of patients using a single bone marrow aspirate smear plus peripheral haemogram results, and in 95.1% using an additional bone marrow biopsy; 4.9% required multiple-site bone marrow examination. Clonal chromosomal abnormalities occurred in 3.9% and 31.8% of patients with AA and MDS, respectively. In patients with severe AA, 12.0% received antithymocyte globulin (ATG) + cyclosporin A (CSA; effectiveness rate 77.8%; 5-year survival 74.1%), 45.3% received CSA + androgen therapy (effectiveness rate 58.8%; 5-year survival 76.5%) and 26.7% received androgen monotherapy (effectiveness rate 25.0%). Multivariate analysis of prognostic factors indicated that therapy regimen and blood platelet count affected survival. Peripheral blood smears, bone marrow spicule classification and biopsy are important diagnostic factors. Standardization of evidence-based therapy and promotion of ATG + CSA would improve general therapeutic effects in AA.

Antithymocyte globulin and cyclosporine in children with aplastic anemia: a developing country experience

BACKGROUND

Human leukocyte antigen-matched bone marrow transplant in the treatment of aplastic anemia is generally not feasible in developing countries due to lack of resources and expertise and immunosuppressive therapy (IST) has been used as an alternative. This study aims to report the long-term outcome of children with aplastic anemia treated with IST [antithymocyte globulin (ATG) and cyclosporine] in our hospital.

PROCEDURE

Case files of children with aplastic anemia who received IST from January 2001 to November 2009 were reviewed.

RESULTS

Thirty-five patients with aplastic anemia (14 very severe aplastic anemia; 21 severe aplastic anemia) were given IST. Seven patients expired within 3 months of therapy and were excluded. The analysis was done in 28 patients (24 male and 4 female; 12 very severe aplastic anemia and 16 severe aplastic anemia). The median age was 10 years (range, 5 to 12 y). Ten patients achieved partial response and 4 patients complete response at 1 year with overall response rate of 50%. Three nonresponders received a second course of ATG after 12 months out of which 2 responded. Hence, overall response including second course was 16 (57%). Three patients relapsed after a median interval of 23 months. The median duration of follow-up of 16 responders was 40 months (range, 15 to 119 mo). In the patients with long-term follow-up for >4 years (n = 7), all were surviving and independent of transfusions.

CONCLUSIONS

In a developing country setting, IST with ATG and cyclosporine seems to be a good alternative treatment for aplastic anemia in children.

Antibodies in the treatment of aplastic anemia

Antibodies have been the cornerstone of treatment of acquired aplastic anemia for more than 25 years. Treatment with antithymocyte globulin (ATG) is considered pivotal and the addition of cyclosporine improves the overall response rate. This antibody is heterogeneous and horse ATG is apparently more effective than rabbit ATG. Several issues remain unsolved in relation to the combination of ATG and cyclosporine: cost, toxicity and late clonal disorders. In recent years, alternative immunosuppressive therapy has been proposed and new antibodies have emerged: porcine ATG, alemtuzumab, daclizumab, and rituximab. Experience with these antibodies is limited to a few studies with alemtuzumab being the most promising, but the results are interesting and provocative. More studies are needed to find the perfect antibody.