Healthcare costs and resource utilization in patients with severe aplastic anemia in the US

Purpose: This study aimed to evaluate the healthcare resource utilization (HCRU) and costs for patients with severe aplastic anemia (SAA) using US claims data. Methods: This retrospective, observational database study analyzed claims data from the Truven MarketScan databases. SAA patients aged ≥2 years identified between 2014 and 2017 who were continuously enrolled for 6 months before their first SAA treatment or blood transfusion, with a ≥6-month follow-up, were included. Baseline demographics and comorbidities were evaluated. Monthly all-cause and SAA-related HCRU and direct costs in the follow-up period were analyzed and differences were presented for all patients and across age groups. Results: With an average follow-up period of 21.5 months, 939 patients were included in the study. Monthly all-cause and SAA-related HCRU [mean (SD)] were 1.65 days (2.61 days) and 0.18 days (0.70 days) for length of stay, 0.18 (0.23) and 0.01 (0.04) for hospital admissions, 0.25 (0.30) and 0.02 (0.07) for ER visits, 2.24 (1.40) and 0.46 (0.99) for office visits, and 2.90 (2.64) and 0.55 (1.31) for outpatient visits, respectively. On average, SAA patients received 0.15 (0.57) blood transfusions per month. Mean monthly all-cause direct costs were $28,280 USD ($36,127) [US dollars, mean (SD)]. Direct costs related to admissions were $11,433 USD (SD $25,040), followed by $624 USD ($1,703) for ER visits, $528 USD ($694) for office visits, $7,615 USD ($13,273) for outpatient visits, and $5,998 USD ($11,461) for pharmacy expenses. Monthly SAA-related direct costs averaged $7,884 USD (SD $16,254); of these costs, $1,608 USD ($7,774) were from admissions, $47 USD ($257) from ER visits, $127 USD ($374) from office visits, $1,462 USD ($4,994) from outpatient visits, and $4,451 USD ($10,552) from pharmacy expenses. Conclusion: SAA is associated with high economic burden, with costs comparable to blood malignancies, implying that US health plans should consider appropriately managing SAA while constraining the total healthcare costs when making formulary decisions.

A cohort study of immune and hematopoietic functionality changes in severe aplastic anemia patients treated with immunosuppressive therapy

To investigate if variations in immune and hematopoietic parameters correlated with immunosuppressive therapy (IST) in severe aplastic anemia (SAA) patients.A total of 115 SAA patients who received IST were included. Their immune and hematopoietic functionality changes had been evaluated at 0, 0.5, 1, 2, and 3-year(s) IST.For SAA patients with complete remission (CR), the CD4/CD8T cell ratio continued to increase after a year of IST. The T helper (Th)1/Th2 ratio continued to decrease after 6 months of IST, as did the activated CD8 T cell percentage. The myeloid dendritic cell (mDC)/plasmacytoid dendritic cell (pDC) ratio after 3 years of IST was significantly lower compared to that of untreated patients. The mDC/pDC and Th1/Th2 ratios exhibited positive correlation. The activated CD8 T cell percentage and the number of peripheral blood neutrophils showed inverse correlation. For SAA patients with partial remission (PR), the CD4T cell percentage increased at 1-year post-IST, but the later changes were not statistically significant. The other immune indexes of patients in partial remission group and nonremission (NR) group showed no obvious recovery. For all SAA patients, the percentage of T regulatory cells in CD4 lymphocyte was higher in post-IST group compared to the pretreatment group.For SAA patients responded well to IST, increase in peripheral neutrophils and improvement in bone marrow myeloid cells were first observed followed reduction in the activated CD8 T cell percentage, Th1/Th2 ratio, CD4/CD8T ratio, along with mDC/pDC ratio, all of which negatively correlated with the hematopoietic parameters. This demonstrates that IST prompts improvements of hematopoietic functionalities of the SAA patients by regulating their immune functionalities.

A brief, but comprehensive, guide to clonal evolution in aplastic anemia

Acquired aplastic anemia (AA) is an immune-mediated bone marrow aplasia that is strongly associated with clonal hematopoiesis upon marrow recovery. More than 70% of AA patients develop somatic mutations in their hematopoietic cells. In contrast to other conditions linked to clonal hematopoiesis, such as myelodysplastic syndrome (MDS) or clonal hematopoiesis of indeterminate potential in the elderly, the top alterations in AA are closely related to its immune pathogenesis. Nearly 40% of AA patients carry somatic mutations in the PIGA gene manifested as clonal populations of cells with the paroxysmal nocturnal hemoglobinuria phenotype, and 17% of AA patients have loss of HLA class I alleles. It is estimated that between 20% and 35% of AA patients have somatic mutations associated with hematologic malignancies, most characteristically in the ASXL1, BCOR, and BCORL1 genes. Risk factors for evolution to MDS in AA include the duration of disease, acquisition of high-risk somatic mutations, and age at AA onset. Emerging data suggest that several HLA class I alleles not only predispose to the development of AA but may also predispose to clonal evolution in AA patients. Long-term prospective studies are needed to determine the true prognostic implications of clonal hematopoiesis in AA. This article provides a brief, but comprehensive, review of our current understanding of clonal evolution in AA and concludes with 3 cases that illustrate a practical approach for integrating results of next-generation molecular studies into the clinical care of AA patients in 2018.

[Acquired aplastic anemia: recent advances in pathophysiology and treatment]

Acquired aplastic anemia (AA) is an autoimmune disease caused by T cells specific to hematopoietic stem cells (HSCs). The presence of HLA allele-lacking leukocytes due to uniparental disomy of the short arm of chromosome 6 (6pUPD) or allelic mutations strongly indicates the involvement of such cytotoxic T cells in the pathogenesis of AA. Attempts to improve treatment outcomes by intensification of immunosuppressive therapy (IST) have been unsuccessful. Eltrombopag (EPAG), a thrombopoietin receptor agonist, has recently emerged as a novel therapeutic agent for AA. EPAG directly acts on HSCs and stimulates proliferation, thereby achieving remission in approximately 40% AA patients refractory to IST. However, some cases develop chromosomal aberrations during treatment. Because somatic mutations are common in patients with AA, verifying whether EPAG induces clonal proliferation or evolution of mutant HSCs is critical.

Hematopoietic development: a gap in our understanding of inherited bone marrow failure

Inherited bone marrow failure syndromes (IBMFS) represent a heterogeneous group of multisystem disorders that typically present with cytopenia in early childhood. Efforts to understand the underlying hematopoietic stem cell (HSC) losses have generally focused on postnatal hematopoiesis. However, reflecting the role of many of the involved genes in core cellular functions and the diverse nonhematologic abnormalities seen in patients at birth, studies have begun to explore IBMFS manifestations during fetal development. Here, I consider the current evidence for fetal deficits in the HSC pool and highlight emerging concepts regarding the origins and unique pathophysiology of hematopoietic failure in IBMFS.

Nutritional support contributes to recuperation in a rat model of aplastic anemia by enhancing mitochondrial function

OBJECTIVES

Acquired aplastic anemia (AA) is a hematopoietic stem cell disease that leads to hematopoietic disorder and peripheral blood pancytopenia. We investigated whether nutritional support is helpful to AA recovery.

METHODS

We established a rat model with AA. A nutrient mixture was administered to rats with AA through different dose gavage once per day for 55 d. Animals in this study were assigned to one of five groups: normal control (NC; group includes normal rats); AA (rats with AA); high dose (AA + nutritional mixture, 2266.95 mg/kg/d); medium dose (1511.3 mg/kg/d); and low dose (1057.91 mg/kg/d). The effects of nutrition administration on general status and mitochondrial function of rats with AA were evaluated.

RESULTS

The nutrient mixture with which the rats were supplemented significantly improved weight, peripheral blood parameters, and histologic parameters of rats with AA in a dose-dependent manner. Furthermore, we observed that the number of mitochondria in the liver, spleen, kidney, and brain was increased after supplementation by transmission electron microscopy analysis. Nutrient administration also improved mitochondrial DNA content, adenosine triphosphate content, and membrane potential but inhibited oxidative stress, thus, repairing the mitochondrial dysfunction of the rats with AA.

CONCLUSIONS

Taken together, nutrition supplements may contribute to the improvement of mitochondrial function and play an important role in the recuperation of rats with AA.

Efficacy and advantages of modified Traditional Chinese Medicine treatments based on "kidney reinforcing" for chronic aplastic anemia: a randomized controlled clinical trial

OBJECTIVE

To compare the efficacy of modified treatments based on "kidney reinforcing" in the management of chronic aplastic anemia (CAA), and explore their advantages and specialties.

METHODS

One hundred and eleven patients with CAA were randomly divided into three groups: kidney reinforcing alone (KA), "kidney reinforcing and Qi tonifying" (KQ), and "kidney reinforcing and blood circulation invigorating" (KC). Normal and positive control groups were also formed. All patients were treated for 6 months (two courses). Hemograms, Traditional Chinese Medicine (TCM) syndrome scores, and therapeutic effects were assessed, and changes in T-lymphocyte subsets, regulatory T cells and cytokines were detected.

RESULTS

The KQ and KC groups had lower TCM syndrome scores than the positive control group after 6 months (P < 0.05). The KQ group had a higher overall efficacy than the positive control group after 3 months (P < 0.05), while platelet counts increased in the KC group after 6 months (P < 0.05). CD3+ T-lymphocyte ratios decreased only in the KQ group, while CD3 + CD4 + CD8 − Tlymphocytes increased only in the KC group after 6 months (P < 0.05). Levels of interferon-γ, tumor necrosis factor tor-α, interleukin (IL)-2 and IL-6 decreased and levels of IL-4 and IL-10 increased in all treated groups after 6 months. Levels of IL-6 in the KQ and KC groups were lower than those in the positive control group (P < 0.05).

CONCLUSION

Treatments based on kidney reinforcing have a rebalancing effect on cytotoxic and T helper cells, and regulate expression of interferon- γ, IL-2, IL-6 and IL-4. KQ may be more effective in treating CAA, and KC may have an advantage in platelet recovery.

Unusual Anemias

Many processes lead to anemia. This review covers anemias that are less commonly encountered in the United States. These anemias include hemoglobin defects like thalassemia, bone marrow failure syndromes like aplastic anemia and pure red cell aplasia, and hemolytic processes such as paroxysmal nocturnal hemoglobinuria. The pathogenesis, diagnostic workup, and treatment of these rare anemias are reviewed.

[Effects of pre-immunosupressive therapy iron overload on hematologic response of severe aplastic anemia]

OBJECTIVE

To explore the effects of serum ferritin (SF) and iron overload (IO) pre-immunosupressive treatment (IST) on hematologic response of severe aplastic anemia (SAA/VSAA) patients treated with IST.

METHODS

257 SAA/VSAA patients who underwent first-line IST from Feb, 2003 to Dec, 2011 in Anemia Therapeutic Centre, Institute of Hematology and Blood Diseases Hospital were retrospectively analyzed, the status of SF before IST and the IO-affected factors were studied. The effects of IO on hematologic response of SAA/VSAA patients were evaluated as well.

RESULTS

The median level of SF of 257 patients was 387 (6-2 004) μg/L. 36 patients (14%) had IO, including 20 SAA and 16 VSAA patients. According to univariate logistical regression analyses, IO was influenced by age>14 years (P=0.010) and blood transfusion (P<0.001). The multivariate logistic regression analysis showed that blood transfusion [P=0.001, OR=0.218 (95% CI 0.092-0.520)] was the only independent prognostic factor. SAA (but not for VSAA) patients with IO had much lower hematologic response rate in 6 month after IST (P=0.037). Absolute reticulocyte count and IO correlated with response at 6 month by univariate logistical regression analysis (P=0.014, 0.037). The multivariate logistic regression analysis showed that IO [P=0.021, OR=4.092 (95% CI 1.235-13.563)], ARC ≥20×10(9)/L [P=0.040, OR=2.743 (95% CI 1.049-7.175)] were independent prognostic factors.

CONCLUSION

84.8% patients had high serum ferritin before IST, and 14.0% reached IO. Adult and more blood transfusion caused IO more likely. IO correlated with response at 6 month, and was independent prognostic factor.

Hemoperitoneum from corpus luteum rupture in patients with aplastic anemia

BACKGROUND

Aplastic anemia is a rare hematopoietic stem-cell disorder that results in pancytopenia and hypocellular bone marrow. Women with aplastic anemia usually are at increased risk of corpus luteum rupture due to thrombocytopenia and infection.

METHODS

Here we report two cases had hemoperitoneum from corpus luteum rupture in patients with aplastic anemia in our center.

RESULTS

Case 1 involved two episodes of hemoperitoneum resulting from rupture of the corpus luteum in a 23-year-old unmarried female with severe aplastic anemia. This patient was managed conservatively with platelet and packed red cell transfusion. Case 2 involved two episodes of hemoperitoneum resulting from rupture of the corpus luteum in a 33-year-old married patient with aplastic anemia. Emergency laparoscopy revealed massive hemoperitoneum. Bilateral salpingo-oophorectomy were performed successively with platelet and packed red cell transfusion.

CONCLUSIONS

Hemoperitoneum resulting from a ruptured corpus luteum is a life-threatening condition in patients with aplastic anemia. Prompt and appropriate evaluation of corpus luteum rupture and emergent therapy are needed.

Epidemiology, Clinico-Haematological Profile and Management of Aplastic Anaemia: AIIMS Experience

BACKGROUND

The incidence of aplastic anaemia (AA) is higher in Asia than in the West. The precise incidence of AA in India is not known due to lack of epidemiological study. 20-40% of pancytopenic patients in referral centres are of aplastic anaemia.

PATIENTS AND METHODS

This was an analysis of 1501 patients diagnosed with aplastic anaemia over a period of seven and half years (January 2007- June 2014) attending the Aplastic clinic of department of haematology of All India Institute of Medical Sciences, New Delhi. The details regarding medical history, physical examination, complete blood count, bone marrow aspirate and biopsy, treatment received, were retrieved. Inherited bone marrow failure was screened in patients below 35 years. Treatment response was analysed for various treatment modalities.

RESULTS

1501 patients of AA from 20 different states of India were analysed. The bulk of patients were from Uttar Pradesh (28.7%), Bihar (23.6%), Delhi/NCR (20%) and Haryana (7%).The average number of new aplastic anaemia patients enrolled per year 214 (range: 101 -263). The median age at presentation was 25 years (range 2-83),with M;F - 2.3:1. Severity of AA revealed: severe (SAA): 75%, very severe (VSAA): 15%, non-severe (NSAA): 10%. Inherited bone marrow failure syndromes constituted 5% (75 patients) of all aplastic anaemia patients. The most common clinical presentations were pallor (97%), bleeding manifestations (69.6%) and fever (54%). The haematological parameters showed: median level of haemoglobin level: 5.9 gm/dL, WBC: 2700/mm3, ANC: 380/mm3, platelet: 1 0000/mm3. PNH clone was present in 13.5% of patients. 107 patients (7%) were lost to follow up or expired before any treatment was initiated. Only 69 patients (4.5%) received treatment with HLA-matched sibling stem cell transplantation and another 232 (15.5%) patients received ATG plus cyclosporine as immunosuppressive therapy. Seven hundred thirteenpatients (47.5%) received cyclosporine. The overall response to various treatment modalities was: HLA matched sibling haematopoietic stem cell transplant: 75.3%, Anti-thymocyte globulin plus cyclosporine: 58.7%, cyclosporine plus androgen: 45.6%, cyclosporine alone: 32.2%.

CONCLUSION

Management of AA is a real challenge in developing countries.This is one of the largest case series from a single centre from India. It is our endeavour to reduce the detrimental outcome by increasing awareness among patients and referring physicians to reduce the delay between diagnosis and treatment.

Immunosuppressive Therapy and Bone Marrow Transplantation for Aplastic Anaemia--The CMC Experience

This is a single centre experience on the use of immunosuppressive therapy (IST) and stem cell transplantation (SCT) in patients with aplastic anaemia. Between 1985 and December 2013, 530 patients underwent IST while 214 underwent allogeneic SCT. Overall response rate with the use of IST was 58% with higher responses seen in adults (65.1%) compared to children (35.8%) [p = 0.001]. At a median follow up of 34 months (range: 1 - 264), 5 year KM estimates for OS for the entire group is 68.2 ± 2.2%. Loss of response or relapse was seen in 27 responders while clonal evolution to PNH was seen in 8 patients and transformation to MDS or AML was seen in 3. The 5 yr OS for children (45.7 ± 4.7%) was significantly lower than the OS of age groups 16-30 (75.6 ± 3.6%), 31-50 years (76.2 ± 4.2%) and > 50 years (73.0 ±4.2%) (p = 0.0001). SCT was performed in 214 patients with engraftment seen in 91%. The incidence of grade II-IV acute graft versus host disease (GVHD) was 38.4% with grade III-IV GVHD in 11.7%. Chronic GVHD was seen in 47.5% of evaluable patients with majority (73%) being limited chronic GVHD. At a median follow up of 32 months (range: 1 - 244), the 5 year KM estimates of OS for the entire cohort is 64.8 ± 3.3%); The 5 yr OS was significantly higher with the use of Flu/Cy (5 yr OS of 73.8 ± 3.6%) compared to Cy/ATG (5 yr OS of 44.4 ± 9.6%) or Flu/Bu conditioning (5 yr OS of 52.4 ± 8.9%) [p = 0.001]. Imp: SCT and IST offer good response rates and survival in Indian patients with AA except in children receiving IST.

[Particular features of erythropoiesis in high altitude and possibilities of applying of hypoxic hypoxia methodology for the patients with hemopoietic suppression]

Conditions of hypoxic hypoxia at 3200 m height exert significant positive changes in hemopoiesis, normalizing erythropoiesis and coagulation system. Hypoxic climate therapy can be regarded as an additional efficient method to the pathogenetic treatment for patient with unpainful aplastic anemia and idiopathic thrombocytopenic purpura. It should be emphasized that patients must be out of immunosuppressive therapy when getting high altitude stationary.

Current concepts in the pathophysiology and treatment of aplastic anemia

Historically viewed in isolation as an odd, rare, and invariably fatal blood disease, aplastic anemia is now of substantial interest for its immune pathophysiology, its relationship to constitutional BM failure syndromes and leukemia, and the success of both stem cell transplantation and immunosuppressive therapies in dramatically improving survival of patients. Once relegated to a few presentations in the red cell and anemia sessions of the ASH, the Society now sponsors multiple simultaneous sessions and plenary and scientific committee presentations on these topics. This update emphasizes developments in our understanding of immune mechanisms and hematopoietic stem cell biology and new clinical approaches to stem cell stimulation as a therapy, alone and in combination with conventional suppression of the aberrant immune system.

[Magnetic resonance imaging and spectroscopy of the bone marrow in children with common hematological diseases]

OBJECTIVE

To evaluate the magnetic resonance (MR) imaging and proton magnetic resonance spectroscopy ((1)H-MRS) in the diagnoses of pediatric hematological diseases.

METHODS

A total of 35 cases with pediatric hematological diseases were confirmed by bone marrow puncturing. There were acute leukemia (n = 26), aplastic anemia (n = 6), thalassemia (n = 2) and autoimmune hemolytic anemia (n = 1). Thirty age-marched healthy children underwent MR imaging (T(1)WI, T(2)WI, STIR) and (1)H-MRS of lumber spine and ilium. The lumber spines and iliums were studied by observation of MR imaging and calculation of fat fraction (FF%).

RESULTS

Two patterns were classified by MR imaging and (1)H-MRS in lumber spines and iliums of all cases. Pattern 1: hyperplasia of bone marrow (BM). There were acute leukemia (n = 26), thalassemia (n = 2) and autoimmune hemolytic anemia (n = 1). The manifestations included homogeneous low signal intensity (SI) on T(1)WI, homogeneous low SI on T(2)WI, high SI on STIR and high water peak and low fat peak on (1)H-MRS. The FF%s of Regions of Interest (ROI) in lumber 4s and left iliums of 26 cases with acute leukemia were 0%, of 3 cases with thalassemia or autoimmune hemolytic anemia were 5.02% and 3.70%. Pattern 2: inhibition of BM. There were 6 cases of aplastic anemia. The manifestations included homogeneous or inhomogeneous high SI on T(1)WI and T(2)WI, homogeneous or inhomogeneous low SI on STIR, and low water peak and high fat peak on (1)H-MRS. FF%s of ROI in lumber 4s and left iliums for 6 cases of aplastic anemia were 74.69% and 91.51%. FF% in all groups had significant differences according to the Mann-Whitney test (P < 0.05).

CONCLUSIONS

MR imaging and (1)H-MRS may serve as a noninvasive method for checking hematopoietic status of bone marrow in pediatric hematological diseases.

Susceptibility to aplastic anemia is associated with HLA-DRB1*1501 in an aboriginal population in Sabah, Malaysia

The incidence of aplastic anemia is reported to be higher in Asia than elsewhere. We studied the frequency of human leukocyte antigen (HLA) DRB1 alleles in aplastic anemia patients from 2 genetically similar aboriginal groups, the Kadazan and the Dusun, and compared them with genetically matched community and hospital controls. HLA-DRB1*15 was significantly higher in the patients compared with controls (p = 0.005), confirming similar findings in Japanese and Caucasian studies. Further testing indicated a significantly higher frequency of HLA-DRB1*1501 in patients compared with controls (p = 0.0004) but no significant difference in the frequency of HLA-DRB1*1502. The high frequency of HLA-DRB1*15 in the Kadazan and Dusun population combined with the wide variety of environmental factors associated with aplastic anemia could be the reason for the elevated incidence of aplastic anemia in the Kadazan and Dusun in Sabah.

[Serial FDG-PET evaluation of a patchy pattern of hematopoiesis at diagnosis in aplastic anemia]

We investigated the hematopoietic status of aplastic anemia with FDG-PET before and after immunosuppressive therapy. FDG-PET showed a patchy uptake pattern before treatment, indicating residual compensatory hypercellular marrow. Three years after successful treatment with ATG plus CsA, the heterogeneity of bone marrow uptake persisted, suggesting that expanded reconstitution of hematopoiesis may require a long time even after the achievement of hematological remission.

Childhood obesity and outcomes after bone marrow transplantation for patients with severe aplastic anemia

The prevalence of obesity in the pediatric population has increased in the last 2 decades and represents a serious health concern, with potential impact on outcomes of hematopoietic cell transplantation (HCT). We studied the effect of weight by age-adjusted body mass index (BMI) percentile in 1,281 pediatric patients (age 2-19 years) with severe aplastic anemia who underwent HCT between 1990 and 2005. The study population was divided into 5 weight groups-underweight, risk of underweight, normal BMI range, risk of overweight, and overweight-according to age-adjusted BMI percentiles. Cox proportional hazards regression models for survival and acute graft-versus-host disease (aGVHD), performed using weight groups as the main effect and the normal BMI range (26th-75th percentile) as the baseline comparison, found higher mortality among overweight children (>95th percentile adjusted for age). Weight at transplantation did not increase the adjusted risk of grade III-IV aGVHD. The 1-year and 2-year overall survival rates were 60% and 59% for overweight children, compared with >70% in children with lower BMI at both time points (P < .001). Other significant factors associated with survival included race and region, donor type, conditioning regimens in related donor transplants, performance score, and year of transplantation. In conclusion, overweight children with aplastic anemia have worse outcomes after HCT. The impact of obesity on survival outcomes in children should be discussed during pretransplantation counseling.

Autoantibodies specific to hnRNP K: a new diagnostic marker for immune pathophysiology in aplastic anemia

To identify a new diagnostic marker for the immune pathophysiology of aplastic anemia (AA), we screened sera of immune-mediated AA patients for the presence of antibodies (Abs) specific to proteins derived from a leukemia cell line UT-7 using two-dimensional electrophoresis followed by immunoblotting. The target proteins were identified by peptide mass fingerprinting. Heterogeneous nuclear ribonucleoprotein (hnRNP) K was identified as a novel autoantigen. An enzyme-linked immunosorbent assay revealed high titers of anti-hnRNP K Abs in 85 (31%) of 273 patients with AA. Sixty-four patients received antithymocyte globulin and cyclosporine after undergoing screening for anti-hnRNP K Ab, anti-DRS-1 Ab, anti-moesin Ab, and paroxysmal nocturnal hemoglobinuria (PNH)-type cells. Twenty (87%) of 23 patients with the presence of anti-hnRNP K Abs responded to the immunosuppressive therapy (IST), while 19 (46%) of 41 patients without the presence of anti-hnRNP K Abs responded. A multivariate analysis showed only PNH-type cells and anti-hnRNP K Abs to be significant factors for the prediction of a good response to IST. The detection of anti-hnRNP K Abs as well as PNH-type cells may therefore be useful for diagnosing the immune pathophysiology of AA.

Aplastic anemia: pathophysiology and treatment

An immune basis for most patients with aplastic anemia (AA) provides a rationale for immunosuppressive therapy (IST), using antithmyocyte globulin and cyclosporine as one therapeutic modality; hematologic response is observed in up to 75% of patients. Recent advances in understanding the pathogenesis of AA have identified defective telomere maintenance as an important explanation for the onset of marrow failure, relapse and clonal evolution after IST, in some patients with AA. The finding of inherited mutations in the telomerase gene complex in patients with apparent acquired AA has important implications for clinical management. Hematopoietic stem cell transplantation (HSCT) for acquired AA, whether from an HLA identical sibling or an unrelated donor, provides an excellent chance of long term cure. Current issues with HSCT include graft rejection, chronic GVHD and poor outcome in older patients. The lack of a suitable bone marrow donor for all patients who need a transplant, illustrates the need for novel transplant procedures, such as cord blood transplantation.

A case of acquired aplastic anemia with repeated cerebral infarctions at the beginning of immunosuppressive therapy

Acquired aplastic anemia is a rare hematopoietic stem-cell disorder that results in pancytopenia and hypocellular bone marrow. The pathophysiology is immune mediated in most cases, with activated type 1 cytotoxic T cells implicated. Acquired aplastic anemia can now be cured or ameliorated by stem-cell transplantation or immunosuppressive drug therapy such as antithymocyte globulin or cyclosporine. We present a rare case report of a 68-year old patient with acquired severe aplastic anemia with repeated cerebral infarctions at the beginning of immunosuppressive therapy. He started immunosuppressive drug therapy with antithymocyte globulin and cyclosporine. During follow-up, magnetic resonance imaging revealed high signals at right thalamus and right pons by diffusion-weighted image. He was diagnosed with repeated cerebral infarctions of right thalamus and right pons. We successfully managed cerebral infarctions by frequent transfusions, edaravone administration, keeping the trough of serum cyclosporine (CsA) concentration around lower limit. This is the first report of successful management of acquired aplastic anemia with repeated cerebral infarctions.

The concurrent presentation of minimal change nephrotic syndrome and aplastic anemia

Minimal change nephrotic syndrome (MCNS) has been associated with primary immunological disorders, such as lymphoma and thymoma. While several different explanations have been proposed, much of the literature has implicated activated T-lymphocytes in the pathogenesis. We report a patient with minimal change nephrotic syndrome presenting concurrently with thrombocytopenia and anemia, with a subsequent diagnosis of aplastic anemia. To our knowledge, this is the first such case described in the literature.

Mitochondrial DNA aberrations of bone marrow cells from patients with aplastic anemia

This study was undertaken primarily to test the hypothesis that mitochondrial DNA (mtDNA) mutations may be associated with aplastic anemia. Complete mtDNA nucleotide sequence was analyzed in nine and eight bone marrow specimens from Korean patients with aplastic anemia and healthy individuals, respectively. We found a large number of polymorphisms as well as apparent new mutations in both patients and controls throughout the entire mtDNA genome; 12 mutations harbored amino acid changes in patients and none of the mutations in controls produced amino acid changes. There were heteroplasmic mutations and more nonsynonymous mtDNA changes observed in patients, so the mean number of mtDNA aberrations of bone marrow cells showed statistically significant difference overall between patients (mean=25.6) and controls (mean=12.8) (p=0.019). Our data may support an association of mtDNA aberrations with aplastic anemia.

[Hematopoiesis support of mesenchymal stem cells in children with aplastic anemia]

OBJECTIVE

The abnormality of hemopoietic inductive microenvironment (HIM) is involved in the pathophysiology of aplastic anemia (AA). Mesenchymal stem cells (MSC) are main source of bone marrow stromal cells which constitute the bone marrow HIM. Thus, the bone marrow failure in AA may be related to the function of MSC. The aim of the study was to investigate the hematopoiesis support function of MSC in children with AA in vitro.

METHODS

Bone marrow samples were collected from 24 children with AA at diagnosis and 19 children with idiopathic thrombocytopenic purpura (ITP), infectious mononucleosis or lymphadenitis (controls). MSCs from bone marrow samples were isolated, cultured and expanded. Morphology, proliferation activity and colony forming unit-fibroblast (CFU-F) were measured. The ability of bone marrow MSC to adhere hemopoietic cells was assayed by MTT. The concentration of stem cell factor (SCF) released from MSC was tested using ELISA. Mononuclear cells (MNC) of bone marrow were plated onto a feeder layer formed by MSC. Cells count and BFU-E, CFU-GM, CFU-GMME productions were measured.

RESULTS

The first and third passage time of MSC in children with AA was longer than that in the controls. The number of CFU-F in children with AA (15.70+/-5.78) was less than that in the controls (21.73+/-5.74) (P<0.05). The concentration of SCF in MSC supernatants in children with AA (30.69+/-16.82 pg/mL) was significantly lower than the controls (50.74+/-14.83 pg/mL) (P<0.01). The total MNC count and the number of BFU-E, CFU-GM and CFU-GMME colonies in the support of MSC in children with AA were significantly lower than those in the controls (P<0.01).

CONCLUSIONS

The hematopoiesis support function of MSC was significantly reduced in children with AA in vitro. The decreased hematopoiesis support function of MSC may be related its decreased proliferation capacity and SCF release activity.

Association of human leukocyte antigen-DRB1 alleles with disease susceptibility and severity of aplastic anemia in Korean patients

Although association of human leukocyte antigen (HLA)-DR2 (DRB1*1501) with susceptibility to aplastic anemia (AA) has been well documented in several different ethnic groups, little is known about the protective role of HLA in this disease. HLA-DRB1 alleles were analyzed in 109 Korean AA patients (26 nonsevere and 83 severe) and 800 healthy controls. The frequency of DRB1*1501 was significantly higher in AA patients compared with controls [33.0% vs 15.3%, p=0.000004, p(c)=0.0001, odds ratio (OR)=2.74]. Nonsevere AA (30.8%, OR=2.47) and severe AA patients (33.7%, OR=2.83) showed similar changes, and DRB1*1501 was considered a susceptibility factor to AA in both forms of the disease. The frequency of DRB1*1302 in total AA patients was not different from controls (12.8% vs 17.9%), but it was significantly lower in severe AA compared with nonsevere AA patients (6.0% vs 34.6%, p=0.0006, p(c)=0.02, OR=0.12). DRB1*1302 was considered a protective factor against severe AA. In Koreans, DRB1*1501 was associated with disease susceptibility to AA and DRB1*1302 with protection against the severe form of the disease.

Aplastic anemia

PURPOSE OF REVIEW

Most acquired aplastic anemia is the result of immune-mediated destruction of hematopoietic stem cells causing pancytopenia and an empty bone marrow, which can be successfully treated with either immunosuppressive therapy or hematopoietic stem-cell transplantation.

RECENT FINDINGS

In aplastic anemia, oligoclonally expanded cytotoxic T cells induce apoptosis of hematopoietic progenitors. T-bet, a transcription factor that binds to the interferon-gamma promoter region, is upregulated in aplastic anemia T cells. Regulatory T cells are significantly reduced in patients' peripheral blood and in an aplastic anemia murine model, infusion of regulatory T cells ameliorates disease progression. In a minority of cases, loss-of-function mutations in telomerase complex genes may underlie disease development. Long-term survival, once strongly linked to response to immunosuppressive therapy, can now be achieved even among nonresponders due to significant advances in supportive care and better salvage treatments.

SUMMARY

Evidence has accumulated in the recent years further corroborating an immune-mediated process underlying aplastic anemia pathogenesis. Hematopoietic stem-cell transplantation from a matched sibling donor is preferred for children and young adults with severe aplastic anemia, and immunosuppressive therapy is employed when hematopoietic stem-cell transplantation is not feasible due to age, lack of a histocompatible sibling, co-morbidities, or by patient choice.

Posthepatitis aplastic anaemia presenting only with bilateral vision loss

Aplastic anaemia is pancytopenia with marrow hypocellularity. Hepatitis-associated aplastic anaemia is a varient or aplastic anaemia that follows an acute attack of seronegative hepatitis. Here a case of hepatitis-associated aplastic anaemia presenting with sudden onset of severe simultaneous bilateral vision loss and without any other usual presenting signs is reported. Partial recovery of blood cell count occurred following immunosuppressive therapy. Posterior hyalodotmy helped rapid resolution of premacular subhyaloid haemorrhage. Although bilateral vision loss may rarely be the initial presentation of aplastic anaemia, no such report is known in hepatitis-associated aplastic anaemia. Posthepatitis vision loss needs careful investigation to exclude an underlying haematological disorder.

Current concepts in the pathophysiology and treatment of aplastic anemia

Aplastic anemia, an unusual hematologic disease, is the paradigm of the human bone marrow failure syndromes. Almost universally fatal just a few decades ago, aplastic anemia can now be cured or ameliorated by stem-cell transplantation or immunosuppressive drug therapy. The pathophysiology is immune mediated in most cases, with activated type 1 cytotoxic T cells implicated. The molecular basis of the aberrant immune response and deficiencies in hematopoietic cells is now being defined genetically; examples are telomere repair gene mutations in the target cells and dysregulated T-cell activation pathways. Immunosuppression with antithymocyte globulins and cyclosporine is effective at restoring blood-cell production in the majority of patients, but relapse and especially evolution of clonal hematologic diseases remain problematic. Allogeneic stem-cell transplant from histocompatible sibling donors is curative in the great majority of young patients with severe aplastic anemia; the major challenges are extending the benefits of transplantation to patients who are older or who lack family donors. Recent results with alternative sources of stem cells and a variety of conditioning regimens to achieve their engraftment have been promising, with survival in small pediatric case series rivaling conventional transplantation results.

[Renin angiotensin system in bone marrow of patients with aplastic anemia]

Renin-angiotensin system (RAS) has been shown to be involved in the growth, production, proliferation and differentiation of the bone marrow (BM) hematopoietic cells, while aplastic anemia (AA) is a disease in which proliferation ability of the BM hematopoietic cells is damaged with defective hematopoietic microenvironment. To investigated the pathogenesis of AA, the rennin activity, angiotensin I (Ang I) and angiotensin II (Ang II) concentration in peripheral blood and BM of 22 AA patients were detected by radioimmunoassay, 16 nonhematological disease patients with normal blood counts and BM picture were used as control, and the difference between two groups was compared. The results showed that BM Ang II concentration in the AA patients was significantly lower than that in the control (P < 0.01). In nonhematological disease patients, Ang II concentration in BM was significantly higher than that in peripheral blood, the renin activities and Ang I concentrations were not significantly different in the two groups (P > 0.05). In conclusion, the decreased BM Ang II concentration in AA patients may be involved to the pathogenesis of AA.

Altered Functional Status of the Hypothalamic Dopaminergic Tone in Patients with Chronic Graft-versus-Host Disease after Allogeneic Hematopoietic Stem Cell Transplantation: A Pilot Study

We compared the functional status of the hypothalamic dopaminergic tone in patients given an allogeneic hematopoietic stem cell transplantation (allo-HSCT) with chronic graft-versus-host disease (GVHD) with that observed in patients with allo-HSCT without chronic GVHD and in healthy controls. The effect of acute dopaminergic blockade with intravenous metoclopramide on serum prolactin (PRL) concentrations was evaluated. Twenty volunteers, 20 to 52 years of age, seronegative for both hepatitis C virus and the human immunodeficiency virus, were studied: (1) 10 clinically healthy men (group 1), and (2) 9 patients with leukemia, and 1 patient with refractory aplastic anemia who underwent allo-HSCT, 5 of whom (3 men and 2 women) developed chronic GVHD (group 2), and 5 (3 men and 2 women) who did not develop chronic GVHD (group 3). Serum PRL concentrations were measured both fasting and after intravenous administration of metoclopramide (10-mg bolus). The area under the PRL curve was calculated. Patients in group 2 were older than those in groups 1 and 3 (P<.018), but their body mass index was similar. Fasting serum PRL concentrations were similar among the 3 groups; however, group 2 had higher PRL concentrations throughout the test (P<.001) and a greater area under the PRL curve than groups 1 and 3 (P<.001), without differences between the last 2 groups. The differences remained significant after adjustment for age (P<.01). Our results in a small group of patients with chronic GVHD after allo-HSCT suggest the existence of an increased functional level of their hypothalamic dopamine tone, which would favor a tendency toward a diminished endogenous production, release of pituitary PRL, or both. This could represent an adaptive mechanism aiming to maintain circulating PRL concentrations within a physiological range.

Bone marrow angiogenesis in aplastic anemia

The objective of this study was to investigate the status of bone marrow angiogenesis in aplastic anemia (AA). Bone marrow specimens from 32 patients with AA and 16 normal controls were studied. The number of bone marrow microvessels was examined by means of immunohistochemical staining for CD34. Determination of microvessel density (MVD) and angiogenesis grading were done in a blinded manner. The results showed that the bone marrow MVD in patients with AA was significantly lower than that in healthy subjects (P < 0.01). MVD in patients with severe and moderate AA was lower than that in control group, respectively (P < 0. 01). There is significant MVD difference between severe AA and moderate AA (P < 0.05). Angiogenesis grade and MVD in AA were positively correlated (r = 0.64, P < 0.01). It is concluded that bone marrow angiogenesis in AA patients is lower than that in normal controls. Defect of angiogenesis in bone marrow may play a role resulting in or aggravating hematopoietic aplasia in patients with AA.

Evaluation of angiogenesis and vascular endothelial growth factor expression in the bone marrow of patients with aplastic anemia

It is generally appreciated that bone marrow function and growth of myelopoietic cells depends on an intact microvasculature. A pivotal regulator of angiogenesis is vascular endothelial growth factor (VEGF). Here, we describe analysis of VEGF expression and microvessel density in the bone marrow of patients with aplastic anemia by immunohistochemistry. Bone marrow was examined at diagnosis and at the time of hematological remission after immunosuppressive therapy using anti-thymocyte globulin, cyclosporin A, and glucocorticoids or allogeneic stem cell transplantation. At diagnosis, both VEGF expression and microvessel density were found to be significantly lower in aplastic anemia compared to normal bone marrow (aplastic anemia, 1.1 +/- 0.7 events per field, versus controls, 5.9 +/- 3.0 events per field; P < 0.05). In response to successful therapy, VEGF and microvessel density in the bone marrow increased substantially. Serum VEGF levels were also found to be significantly lower at diagnosis in aplastic anemia compared to healthy controls (aplastic anemia, 51 +/- 35 pg/ml versus controls, 444 +/- 220 pg/ml; P < 0.05). VEGF in the serum increased substantially after successful immunosuppressive therapy or stem cell transplantation (P < 0.05). Taken together, these data show that aplastic anemia is associated with reduced angiogenesis and reduced VEGF expression.

[Effect of salidroside on bone marrow cell cycle and expression of apoptosis-related proteins in bone marrow cells of bone marrow depressed anemia mice]

OBJECTIVE

To examine the effect of salidroside on bone marrow cell cycle and expression of apoptosis-related proteins in bone marrow cells (BMCs) of bone marrow depressed anemia mice, and to explore its mechanism for hematopoietic regulation.

METHODS

The effect of salidroside on peripheral blood cells, BMCs, and bone marrow cell cycle in bone marrow depressed anemia mice was detected by automatic blood cell analysator, white blood count and flow cytometry (FCM)respectively,and the expression of Bcl-2 and Bax of BMCs was detected by immunohistochemistry method simultaneously.

RESULTS

It was found that low-dose and high-dose salidroside obviously elevated white blood cells and BMCs, that low-dose salidroside significantly increased platelets and promoted G0/G1-S phase and S-G2/M phase transition of BMCs, that high-dose salidroside markedly promoted S-G2/M phase transition of BMCs, and that both low-dose and high-dose salidroside obviously elevated the proliferation index and the ratio of G2/M phase cells. Additionally, the expression of Bcl-2 in BMCs was increased in low-dose and high-dose salidroside groups, especially the increase was significant in the low-dose salidroside group; moreover, the expression of Bax in BMCs was reduced significantly in both low-dose and high-dose salidroside groups.

CONCLUSION

These data suggest that salidroside may promote the recovery of hematopoietic function of the bone marrow depressed anemia in mice by ending off G0/G1-phase arrest, accelerating G0/G1-S phase and S-G2/M phase transition, up-regulating Bcl-2 expression, down-regulating Bax expression, and inhibiting BMCs apoptosis.

Immune Pathophysiology of Aplastic Anemia

Acquired aplastic anemia (AA) is considered an immune-mediated disease because approximately 70% of AA patients improve with immunosuppressive therapy. However, little is known about the inciting antigens or the mechanisms responsible for the destruction of hematopoietic stem cells by immune system attack. Recent advances in immunologic techniques have promoted our understanding of the pathogenesis of AA and have provided evidence that AA is an organ-specific T-cell-mediated disease localized in the bone marrow. Moreover, antibody screening of patients' serum with a complementary DNA library derived from hematopoietic cells has identified several proteins as candidate autoantigens in AA.