Diamond-Blackfan anemia

The inherited bone marrow failure syndromes

Molecular pathogenesis may be elucidated for inherited bone marrow failure syndromes (IBMFS). The study and presentation of the details of their molecular biology and biochemistry is warranted for appropriate diagnosis and management of afflicted patients and to identify the physiology of the normal hematopoiesis and mechanisms of carcinogenesis. Several themes have emerged within each subsection of IBMFS, including the ribosomopathies, which include ribosome assembly and ribosomal RNA processing. The Fanconi anemia pathway has become interdigitated with the familial breast cancer syndromes. In this article, the diseases that account for most IBMFS diagnoses are analyzed.

Diamond-blackfan anemia and growth status: the French registry

OBJECTIVES

To study the frequency and risk factors of growth retardation (GR) in patients with Diamond-Blackfan anemia.

STUDY DESIGN

A cross-sectional survey including the 95 patients followed by hematologists affiliated with the French Society of Pediatric Hematology and Immunology for whom growth data were available; 43 patients were transfusion dependent, 32 were steroid dependent, and 20 patients were off treatment. GR was defined as height below 2 SD.

RESULTS

Growth retardation was observed in 29.5% (28) patients. The proportion of GR increased significantly with age (16% <10, 32% among 10 to 16, 47.6% among 17 to 25, 41.7% among >16 years) and was higher in on-treatment than in off-treatment patients (35% among transfusion-dependent, 37% among steroid-dependent vs 5% among off-treatment). GR was significantly linked to associated malformations (OR, 2.3 [1.1 to 8.0]; P = .02) and intrauterine growth retardation (OR, 6.0 [1.1 to 11.6]; P = .021). GR remained independently associated with age, malformations, and treatment in a logistic regression.

CONCLUSIONS

Our study showed that the risk of GR increases with age and is associated with treatment dependence. This result addresses the question of the respective part, in the pathogenesis of GR, of the disease severity, illustrated by treatment dependence on the one hand and of the deleterious effects of long-term treatments on the other hand.

Diamond-Blackfan anemia in Japan: clinical outcomes of prednisolone therapy and hematopoietic stem cell transplantation

The epidemiology and treatment outcomes for Diamond-Blackfan anemia (DBA) were surveyed in a cohort of 54 children (M/F = 26:28) registered in Japan from 1988 to 1998. The annual incidence was 4.02 cases per million births, the median age at diagnosis was 60 days, and 59% of the cases presented by 3 months of age. Three patients had a familial occurrence. All patients received prednisolone (PSL), and cyclosporin A (CsA) was added to the therapy in 17 patients. Forty-seven patients received transfusions, and 13 underwent hematopoietic stem cell transplantation (HSCT). The cumulative probabilities of a medication-free or a transfusion-free state prior to HSCT were 36% and 69%, respectively, at more than 5 years after diagnosis. Thirteen patients were weaned from PSL therapy without HSCT, and CsA was not associated with weaning from therapy. Transfusion and medication were stopped at 249 days and 933 days after diagnosis in 34 and 13 patients, respectively, who achieved a state of independence. No initial findings predicted the treatment dependence. More than 20% of patients experienced sustained hemosiderosis and/or adverse effects of PSL. The ages and reticulocyte counts at diagnosis of the patients who underwent HSCT were lower than in the patients who did not. HSCT led to the highest success (85%) of all previous reports, even though 5 alternative donors were included in our study. Two cord blood transplants from unrelated donors failed. These findings suggest the need for developing an integral treatment strategy including selective HSCT for refractory DBA.

Study of 22 Egyptian patients with Diamond-Blackfan anemia, corticosteroids, and cyclosporin therapy results

OBJECTIVE

Diamond-Blackfan anemia is a rare congenital hypoproliferative anemia of infancy and early childhood. Treatment with corticosteroids is commonly used, but with limited success. Trials with cyclosporin-A (CSA) are not frequently reported. Therefore, in this study we analyzed our results in the management of this rare disease by different medical treatments.

DESIGN

The results of 22 patients diagnosed at our Hematology Center in the New Cairo University Children's Hospital during the period 1991-2001 were retrospectively analyzed. Our patients first received prednisolone (2 mg/kg/d) for different courses according to their response. Since the year 2000, the steroid nonresponders received CSA (3-12 mg/kg/d) for 6 months unless treatment complications developed.

RESULTS

The age at the onset of the disease ranged from 1 to 24 months (median: 2.5 months). The mean values of the hemoglobin, the reticulocyte count, and the myeloid/erythroid ratio at the onset of the disease were 4.75 +/- 1.79 g/dL, 0.14 +/- 0.16, and 39.4 +/- 27.08, respectively. Patients received prednisolone from 0.25 to 10 years (median: 2 years). Ten patients were nonresponders (45.5%), and 5 patients (22.7%) responded to corticosteroid therapy. Two of 5 responders are off treatment with a hemoglobin level of >9 g/dL, and 3 of 5 are currently corticosteroid-dependent. Of 10 patients not responding to steroids, 8 received CSA for 6 months. Four patients (50%) responded to CSA therapy. A significant positive association was found between CSA dose and response.

CONCLUSION

CSA therapy should be tried in steroid-resistant Diamond-Blackfan anemia patients before blood transfusion or corticosteroid therapy complications are instituted.

Blackfan-Diamond anemia and dyserythropoietic anemia presenting with increased nuchal translucency at 12 weeks of gestation

Blackfan-Diamond anemia is a congenital hypoplastic anemia with a birth prevalence of about 1 in 200,000, usually presenting in the first few months of life and commonly associated with cardiac, urogenital and digital anomalies. Congenital dyserythropoietic anemias are a group of rare congenital anemias characterized by ineffective erythropoiesis. We report on two cases of congenital fetal anemia, one with Blackfan-Diamond anemia and one with dyserythropoietic anemia, presenting with increased nuchal translucency at 12 weeks of gestation.

Pneumocystis carinii pneumonia in patients with Diamond-Blackfan anemia receiving high-dose corticosteroids

The authors describe three infants with Diamond-Blackfan anemia receiving corticosteroids who were diagnosed with Pneumocystis carinii pneumonia. Two patients exhibited intermittent neutropenia as well. Each child had been receiving relatively high doses of corticosteroids for at least 2 months, and two were having prednisone tapered when pneumonia developed. One child responded to trimethoprim/sulfamethoxazole and pentamidine, but the other two patients died. Infants with Diamond-Blackfan anemia receiving prolonged corticosteroid therapy should receive P. carinii pneumonia prophylaxis, such as trimethoprim/sulfamethoxazole, and prophylaxis should continue during corticosteroid tapering.

High-dose methylprednisolone therapy in pure red cell aplasia

OBJECTIVE

To report our experience using high-dose methylprednisolone (HDMP) treatment in a patient with primary acquired pure red cell aplasia (PRCA) who failed to respond to conventional prednisone therapy.

CASE SUMMARY

A 29-year-old woman reported weakness, was easily fatigued, and had developed palpitations. On physical examination, pallor and splenomegaly were detected. On blood smear, mild macrocytic anemia was seen. Bone marrow aspiration and biopsy revealed normocellularity, erythroid hypoplasia (E/M: 1/10), reduction in erythroid precursors, and normal megakaryocytes and myeloid series. No disease associated with secondary PRCA was detected. Oral prednisone 1 mg/kg (total 60 mg/d) was started as conventional treatment. However, the patient's status deteriorated and the hemoglobin concentration fell from 6.5 to 5.5 g/dL within the first week of hospitalization. HDMP was then begun. Treatment protocol consisted of methylprednisolone 30 mg/kg for 4 days, 20 mg/kg for 3 days, 10 mg/kg for 3 days, 5 mg/kg for 4 days, and 1 mg/kg for 2 weeks. The patient's hemoglobin concentration increased from 5.5 to 14.2 g/dL over a period of 9 weeks. Transient hyperglycemia and cushingoid appearance were seen during prednisone treatment.

DISCUSSION

Exactly how steroids enhance erythropoiesis in PRCA is unknown. It seems likely that steroids render abnormal erythroid progenitors more sensitive to marrow growth factors, thereby permitting them to differentiate to functional precursors. HDMP treatment had been rarely used in patients with primary acquired PRCA. Limited studies using HDMP have shown variable results.

CONCLUSIONS

HDMP treatment may be considered safe and effective in patients with primary acquired PRCA who do not respond to conventional steroid therapy.

Diamond-blackfan anemia and cyclosporine therapy revisited

A girl with Diamond-Blackfan anemia diagnosed in infancy started cyclosporine A (CSA) therapy at 9 years and 8 months of age after experiencing unacceptable side effects while receiving prednisone. Since then, she has been followed-up for more than 4 years. She exhibited a dramatic response to CSA, with weaning and then cessation of steroid therapy after 5 months. She has remained transfusion-independent. Attempts to discontinue CSA therapy have been unsuccessful. Relapse of the anemia has occurred in the context of viral infections with missed CSA doses. The major clinical problem during treatment has been recurrent oral aphthous ulceration, which responds to topical therapy. She is currently maintained on CSA 100 mg twice daily with a hemoglobin of 10.2 g/dL and a reticulocyte count of 1.6%. A trial of CSA therapy should be considered in patients with Diamond-Blackfan anemia in whom steroid therapy has failed before a transfusion program is instituted or alternative donor stem cell transplantation is entertained.

Cloning of the cellular receptor for feline leukemia virus subgroup C (FeLV-C), a retrovirus that induces red cell aplasia

Feline leukemia virus-C (FeLV-C) causes red cell aplasia in cats, likely through its interaction with its cell surface receptor. We identified this receptor by the functional screening of a library of complementary DNAs (cDNA) from feline T cells. The library, which was cloned into a retroviral vector, was introduced into FeLV-C–resistant murine (NIH 3T3) cells. The gene conferring susceptibility to FeLV-C was isolated and reintroduced into the same cell type, as well as into FeLV-C–resistant rat (NRK 52E) cells, to verify its role in viral infection. The receptor cDNA is predicted to encode a protein of 560 amino acids with 12 membrane-spanning domains, termed FLVCR. FLVCR has significant amino acid sequence homology with members of the major facilitator superfamily and especially D-glucarate transporters described in bacteria and in C. elegans. As FeLV-C impairs the in vivo differentiation of burst-forming unit–erythroid to colony-forming unit–erythroid, we hypothesize that this transporter system could have an essential role in early erythropoiesis. In further studies, a 6-kb fragment of the human FLVCR gene was amplified by polymerase chain reaction from genomic DNA, using homologous cDNA sequences identified in the human Expressed Sequence Tags database. By radiation hybrid mapping, the human gene was localized to a 0.5-centiMorgan region on the long arm of chromosome 1 at q31.3.

Epstein-Barr virus-associated lymphoproliferative disease after a cord blood transplant for Diamond-Blackfan anemia

A 7-year-old boy with Diamond-Blackfan anemia (DBA) developed lymphoproliferative disease (LPD) after a cord blood transplant (CBT). 3.1 x 107/kg mononuclear cells from an HLA one-locus mismatched CB were transplanted after conditioning with total body irradiation (8 Gy), cyclophosphamide (200 mg/kg) and antithymocyte globulin (10 mg/kg). Complete engraftment occurred on day 33 post transplant. Despite the resolution of grade II graft-versus-host disease (GVHD), he died of lymphoma on day 130 post transplant. The tumor was of donor origin, indicating clonal proliferation of Epstein-Barr virus (EBV)-infected B cells. This is the first report of EBV-LPD after CBT. Post-transplant LPD can be a serious EBV-associated complication of CB grafts. Bone Marrow Transplantation (2000) 25, 209-212.