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Background: Anemia is defined as a lack of erythrocytes, low hemoglobin levels, or abnormal erythrocyte morphology. Diamond-Blackfan anemia (DBA) is a rare and severe congenital hypoplastic anemia that occurs due to the dominant inheritance of a ribosomal protein gene mutation. Even rarer is a case described as Diamond-Blackfan anemia like (DBAL), which occurs due to a loss-of-function EPO mutation recessive inheritance. The effective cures for DBAL are bone marrow transfusion and treatment with erythropoiesis-stimulating agents (ESAs). To effectively manage the condition, construction of DBAL models to identify new medical methods or screen drugs are necessary., Results: Here, an epoa-deficient mutant zebrafish called epoa szy8 was generated to model DBAL. The epoa-deficiency in zebrafish caused developmental defects in erythroid cells, leading to severe congenital anemia. Using the DBAL model, we validated a loss-of-function EPO mutation using an in vivo functional analysis and explored the ability of ESAs to alleviate congenital anemia., Conclusions: Together, our study demonstrated that epoa deficiency in zebrafish leads to a phenotype resembling DBAL. The DBAL zebrafish model was found to be beneficial for the in vivo assessment of patient-derived EPO variants with unclear implications and for devising potential therapeutic approaches for DBAL., (© 2024 American Association for Anatomy.)

Diamond Blackfan Anemia (DBA) is a rare disease characterized by anemia secondary to impaired red blood cell production from bone marrow failure. We present a case of infantile hypothermia and shock caused by this clinical pathology. A seven-week-old infant was brought to the emergency department by the father with the chief complaint of abnormal breathing and low activity level throughout the day. Medical history was unremarkable for both the patient and the family. On examination, the infant was breathing 30 breaths per minutes, had a heart rate of 116, and a core temperature of 33 degrees Celsius. The infant was ashen in color, limp, with grunted breathing and minimal movement. Numerous abnormal laboratory readings were reported, with the most significant being a hemoglobin of 1.7 and a hematocrit of 7.4. Emergent blood transfusion was initiated, and the patient was eventually air-lifted to a pediatric hospital two hours away. This case highlights the imperative of a thorough history and examination and consideration of a broad differential for neonatal hypothermia and shock, especially in the setting of no obvious bleeding., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier Inc.)

The emergence of multiomic single-cell technologies over the last decade has led to improved insights into both normal hematopoiesis and its perturbation in a variety of hematological disorders. Diamond-Blackfan anemia (DBA) syndrome is one such disorder where single-cell assays have helped to delineate the cellular and molecular defects underlying the disease. DBA is caused by heterozygous loss-of-function germline variants in genes encoding ribosomal proteins (RPs). Despite the widespread role of ribosomes in hematopoiesis, the most frequent and severe cytopenia in DBA is anemia. In this review we discussed how single-cell studies, including clonogenic cell culture assays, fluorescence-activated cell sorting (FACS) and single-cell RNA sequencing (scRNA-seq), have led to insights into the pathogenesis of DBA. The main therapies are regular blood transfusions, glucocorticoids, or hematopoietic stem cell transplantation (HSCT) but all are associated with significant morbidity and mortality. We will therefore outline how single-cell studies can inform new therapies for DBA. Furthermore, we discussed how DBA serves as a useful model for understanding normal erythropoiesis in terms of its cellular hierarchy, molecular regulation during homeostasis, and response to "stress.", Competing Interests: Conflict of Interest Disclosure The authors have no conflicts of interest to disclose., (Crown Copyright © 2024. Published by Elsevier Inc. All rights reserved.)

Diamond-Blackfan anemia (DBA) is a rare genetic disorder affecting the bone marrow's ability to produce red blood cells, leading to severe anemia and various physical abnormalities. Approximately 75% of DBA cases involve heterozygous mutations in ribosomal protein (RP) genes, classifying it as a ribosomopathy, with RPS19 being the most frequently mutated gene. Non-RP mutations, such as in GATA1, have also been identified. Current treatments include glucocorticosteroids, blood transfusions, and hematopoietic stem cell transplantation (HSCT), with HSCT being the only curative option, albeit with challenges like donor availability and immunological complications. Gene therapy, particularly using lentiviral vectors and CRISPR/Cas9 technology, emerges as a promising alternative. This review explores the potential of gene therapy, focusing on lentiviral vectors and CRISPR/Cas9 technology in combination with non-integrating lentiviral vectors, as a curative solution for DBA. It highlights the transformative advancements in the treatment landscape of DBA, offering hope for individuals affected by this condition.

This study lays the groundwork for future lentivirus-mediated gene therapy in patients with Diamond Blackfan anemia (DBA) caused by mutations in ribosomal protein S19 (RPS19), showing evidence of a new safe and effective therapy. The data show that, unlike patients with Fanconi anemia (FA), the hematopoietic stem cell (HSC) reservoir of patients with DBA was not significantly reduced, suggesting that collection of these cells should not constitute a remarkable restriction for DBA gene therapy. Subsequently, 2 clinically applicable lentiviral vectors were developed. In the former lentiviral vector, PGK.CoRPS19 LV, a codon-optimized version of RPS19 was driven by the phosphoglycerate kinase promoter (PGK) already used in different gene therapy trials, including FA gene therapy. In the latter one, EF1α.CoRPS19 LV, RPS19 expression was driven by the elongation factor alpha short promoter, EF1α(s). Preclinical experiments showed that transduction of DBA patient CD34+ cells with the PGK.CoRPS19 LV restored erythroid differentiation, and demonstrated the long-term repopulating properties of corrected DBA CD34+ cells, providing evidence of improved erythroid maturation. Concomitantly, long-term restoration of ribosomal biogenesis was verified using a potentially novel method applicable to patients' blood cells, based on ribosomal RNA methylation analyses. Finally, in vivo safety studies and proviral insertion site analyses showed that lentivirus-mediated gene therapy was nontoxic.

Diamond-Blackfan anaemia (DBA), first described over 80 years ago, is a congenital disorder of erythropoiesis with a predilection for birth defects and cancer. Despite scientific advances, this chronic, debilitating, and life-limiting disorder continues to cause a substantial physical, psychological, and financial toll on patients and their families. The highly complex medical needs of affected patients require specialised expertise and multidisciplinary care. However, gaps remain in effectively bridging scientific discoveries to clinical practice and disseminating the latest knowledge and best practices to providers. Following the publication of the first international consensus in 2008, advances in our understanding of the genetics, natural history, and clinical management of DBA have strongly supported the need for new consensus recommendations. In 2014 in Freiburg, Germany, a panel of 53 experts including clinicians, diagnosticians, and researchers from 27 countries convened. With support from patient advocates, the panel met repeatedly over subsequent years, engaging in ongoing discussions. These meetings led to the development of new consensus recommendations in 2024, replacing the previous guidelines. To account for the diverse phenotypes including presentation without anaemia, the panel agreed to adopt the term DBA syndrome. We propose new simplified diagnostic criteria, describe the genetics of DBA syndrome and its phenocopies, and introduce major changes in therapeutic standards. These changes include lowering the prednisone maintenance dose to maximum 0·3 mg/kg per day, raising the pre-transfusion haemoglobin to 9-10 g/dL independent of age, recommending early aggressive chelation, broadening indications for haematopoietic stem-cell transplantation, and recommending systematic clinical surveillance including early colorectal cancer screening. In summary, the current practice guidelines standardise the diagnostics, treatment, and long-term surveillance of patients with DBA syndrome of all ages worldwide., Competing Interests: Declaration of interests AK declares honoraria from chiesi and Novartis and a research grant from Novaris. AK is on the advisory board of Chiesi and Novartis. FML declares honoraria from Chiesi and is on the advisory board of Chiesi. LK is on the advisory board of Agios, Amgen, Bayer, and Novartis. All other authors declare no competing interests., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Abstact: Diamond-Blackfan anemia (DBA) is a rare congenital bone marrow failure disorder characterized by erythroid hypoplasia. It primarily affects infants and is often caused by heterozygous allelic variations in ribosomal protein (RP) genes. Recent studies also indicated that non-RP genes like GATA1, TSR2, are associated with DBA. P53 activation, translational dysfunction, inflammation, imbalanced globin/heme synthesis, and autophagy dysregulation were shown to contribute to disrupted erythropoiesis and impaired red blood cell production. The main therapeutic option for DBA patients is corticosteroids. However, half of these patients become non-responsive to corticosteroid therapy over prolonged treatment and have to be given blood transfusions. Hematopoietic stem cell transplantation is currently the sole curative option, however, the treatment is limited by the availability of suitable donors and the potential for serious immunological complications. Recent advances in gene therapy using lentiviral vectors have shown promise in treating RPS19-deficient DBA by promoting normal hematopoiesis. With deepening insights into the molecular framework of DBA, emerging therapies like gene therapy hold promise for providing curative solutions and advancing comprehension of the underlying disease mechanisms., (© 2023. The Author(s).)

Diamond-Blackfan anemia is a rare genetic bone marrow failure disorder which is usually caused by mutations in ribosomal protein genes. In the present study, we generated a traceable RPS19-deficient cell model using CRISPR-Cas9 and homology-directed repair to investigate the therapeutic effects of a clinically applicable lentiviral vector at single-cell resolution. We developed a gentle nanostraw delivery platform to edit the RPS19 gene in primary human cord bloodderived CD34+ hematopoietic stem and progenitor cells. The edited cells showed expected impaired erythroid differentiation phenotype, and a specific erythroid progenitor with abnormal cell cycle status accompanied by enrichment of TNFα/NF-κB and p53 signaling pathways was identified by single-cell RNA sequencing analysis. The therapeutic vector could rescue the abnormal erythropoiesis by activating cell cycle-related signaling pathways and promoted red blood cell production. Overall, these results establish nanostraws as a gentle option for CRISPR-Cas9- based gene editing in sensitive primary hematopoietic stem and progenitor cells, and provide support for future clinical investigations of the lentiviral gene therapy strategy.

Diamond Blackfan anemia (DBA) is an inherited bone marrow failure syndrome characterized by congenital anomalies, cancer predisposition and a severe hypo-proliferative anemia. It was the first disease linked to ribosomal dysfunction and >70 % of patients have been identified to have a haploinsufficiency of a ribosomal protein (RP) gene, with RPS19 being the most common mutation. There is significant variability within the disease in terms of phenotype as well as response to therapy suggesting that other genes contribute to the pathophysiology and potential management of this disease. To explore these questions, we performed a genome-wide CRISPR screen in a cellular model of DBA and identified Calbindin 1 (CALB1), a member of the calcium-binding superfamily, as a potential modifier of the disordered erythropoiesis in DBA. We used human derived CD34+ cells cultured in erythroid stimulating media with knockdown of RPS19 as a model for DBA to study the effects of CALB1. We found that knockdown of CALB1 in this DBA model promoted erythroid maturation. We also noted effects of CALB1 knockdown on cell cycle. Taken together, our results reveal CALB1 is a novel regulator of human erythropoiesis and has implications for using CALB1 as a novel therapeutic target in DBA., Competing Interests: Declaration of competing interest None., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Diamond-Blackfan anemia is a rare (6-7 million live births), inherited condition manifesting as severe anemia due to the impaired bone marrow production of red blood cells. We present the unusual case of a six month old infant with a de novo mutation of the RPS19 gene causing Diamond-Blackfan anemia who additionally suffers from severe sinus bradycardia. The infant was diagnosed with this condition at the age of four months; at the age of 6 months, she presents with severe anemia causing hypoxia which, in turn, caused severe dyspnea and polypnea, which had mixed causes (hypoxic and infectious) as the child was febrile. After correction of the overlapping diarrhea, metabolic acidosis, and severe anemia (hemoglobin < 3 g/dL), she developed severe persistent sinus bradycardia immediately after mild sedation (before central venous catheter insertion), not attributable to any of the more frequent causes, with a heart rate as low as 49 beats/min on 24 h Holter monitoring, less than the first percentile for age, but with a regular QT interval and no arrhythmia. The echocardiogram was unremarkable, showing a small interatrial communication (patent foramen ovale with left-to-right shunting), mild left ventricular hypertrophy, normal systolic and diastolic function, and mild tricuspid regurgitation. After red cell transfusion and appropriate antibiotic and supportive treatment, the child's general condition improved dramatically but the sinus bradycardia persisted. We consider this a case of well-tolerated sinus bradycardia and foresee a good cardiologic prognosis, while the hematologic prognosis remains determined by future corticoid response, treatment-related complications and risk of leukemia.

Diamond Blackfan anemia (DBA) is a chronic congenital form of erythrocytic hypoplasia in which erythroid precursor cell levels are low. DBA reflects ribosomal dysfunction and is accompanied by hematopoietic cell apoptosis, anemia, and various somatic symptoms. We report the characteristic symptoms of the craniofacial region and the orthodontic treatments of two DBA cases. Case 1 was a 12-year-old female. The typical physical and facial characteristics of DBA were lacking. On initial examination, she exhibited a skeletal Class II jaw and end to end molar relationships and a large overjet. An edgewise appliance was placed after extraction of the first maxillary premolars. After 3 years and 11 months, an appropriate overjet and overbite, rigid intercuspation, and an acceptable profile were evident without any clinical adverse effects. Case 2 was a 13-year-old female. She exhibited a skeletal Class I jaw relationship, a spaced dental arch, the maxillofacial dysplasia characteristic of Binder syndrome, hypoplasia of the right mandibular condyle, and labial protrusions of the maxillary and mandibular incisors. We placed an edgewise appliance and after 1 year and 7 months, the occlusion was optimal in the absence of any adverse effects. Our two DBA cases exhibited a broad spectrum of physical and dentofacial symptoms. Patients with DBA are often prescribed combined steroid/bisphosphonate therapies. Both agents are likely to affect alveolar bone remodeling after tooth extraction and orthodontic tooth movement. Careful consideration of medication with reference to various dentofacial characteristics is necessary.

Transfusion-dependent Diamond-Blackfan anaemia (DBA) patients rapidly develop iron overload and frequently experience cardiac complications. The report by Lecornec and colleagues offers useful details on indications and the management of deferiprone, a highly efficient chelator in removing excess cardiac iron but associated with a high risk of agranulocytosis in DBA patients. Commentary on: Lecornec et al. Agranulocytosis in patients with Diamond-Blackfan anaemia (DBA) treated with deferiprone for post-transfusion iron overload: A retrospective study of the French DBA cohort. British Journal of Haematology 2022;199:285-288., (© 2022 British Society for Haematology and John Wiley & Sons Ltd.)

Diamond-Blackfan anemia (DBA) is an inherited bone marrow failure syndrome, associated with mutations in ribosomal protein (RP) genes. Growing data on mutations in non-RP genes in patients with DBA-like phenotype became available over recent years. We describe two patients with the phenotype of DBA (onset of macrocytic anemia within the first year of life, paucity of erythroid precursors in bone marrow) and germline de novo variants in the TP53 gene. Both patients became transfusion independent, probably due to L-leucine therapy. The possible role of TP53 variants should be considered in patients with DBA-like phenotype and no mutations in RP genes., (© 2022 Wiley Periodicals LLC.)

Diamond-Blackfan anemia (DBA) is an inherited bone marrow failure disorder in which pure red blood cell aplasia is associated with physical malformations and a predisposition to cancer. Twentyfive percent of patients with DBA have mutations in a gene encoding ribosomal protein S19 (RPS19). Our previous proof-of-concept studies demonstrated that DBA phenotype could be successfully treated using lentiviral vectors in Rps19-deficient DBA mice. In our present study, we developed a clinically applicable single gene, self-inactivating lentiviral vector, containing the human RPS19 cDNA driven by the human elongation factor 1a short promoter, which can be used for clinical gene therapy development for RPS19-deficient DBA. We examined the efficacy and safety of the vector in a Rps19-deficient DBA mouse model and in human primary RPS19-deficient CD34+ cord blood cells. We observed that transduced Rps19-deficient bone marrow cells could reconstitute mice long-term and rescue the bone marrow failure and severe anemia observed in Rps19-deficient mice, with a low risk of mutagenesis and a highly polyclonal insertion site pattern. More importantly, the vector can also rescue impaired erythroid differentiation in human primary RPS19-deficient CD34+ cord blood hematopoietic stem cells. Collectively, our results demonstrate the efficacy and safety of using a clinically applicable lentiviral vector for the successful treatment of Rps19-deficient DBA in a mouse model and in human primary CD34+ cord blood cells. These findings show that this vector can be used to develop clinical gene therapy for RPS19-deficient DBA patients.

BACKGROUND Diamond-Blackfan anemia (DBA) is a rare genetic disorder associated with macrocytic anemia and reticulocytopenia, with patients usually transfusion-dependent in the first years of life. The disease inheritance is predominantly autosomal dominant, but varying presentations have been described owing to incomplete penetrance and widely variable expression. De novo mutations have been reported in about 55% of cases. This pediatric disease is commonly characterized by malformation of the extremities as well as craniofacial abnormalities and cardiac and urogenital defects. There have been reported cases of adult-onset DBA diagnosed through genetic testing. Although these adult-onset cases can vary in presentation, characteristic malformations are present in nearly half of patients. Treatment protocols include corticosteroids, blood transfusions, iron chelation, and bone marrow transplant. New investigational therapies are being evaluated. Roughly one-fourth of patients achieve remission and are able to maintain a stable hemoglobin level without intervention. CASE REPORT A 35-year-old woman with spina bifida and resultant paraplegia presented with new-onset transfusion-dependent hypoplastic anemia. Following an extensive evaluation, a RPL11 gene variant was found, confirming the diagnosis of DBA. CONCLUSIONS DBA should be considered in young adult patients with severe, transfusion-dependent, aregenerative anemia without definitive cause. Evaluation for nonclassical DBA should be considered and excluded.

Diamond-Blackfan anemia (DBA) is a rare genetic disorder in which patients present a scarcity of erythroid precursors in an otherwise normocellular bone marrow. Most, but not all, patients carry mutations in ribosomal proteins such as RPS19, suggesting that compromised mRNA translation and ribosomal stress are pathogenic mechanisms causing depletion of erythroid precursors. To gain further insight to disease mechanisms in DBA, we performed a custom short hairpin RNA (shRNA) based screen against 750 genes hypothesized to affect DBA pathophysiology. Among the hits were two shRNAs against the erythroid specific heme-regulated eIF2α kinase (HRI), which is a negative regulator of mRNA translation. This study shows that shRNA-mediated HRI silencing or loss of one HRI allele improves expansion of Rps19-deficient erythroid precursors, as well as improves the anemic phenotype in Rps19-deficient animals. We found that Rps19-deficient erythroblasts have elevated levels of unbound intracellular heme, which is normalized by HRI heterozygosity. Additionally, targeting elevated heme levels by treating cells with the heme scavenger alpha-1-microglobulin (A1M), increased proliferation of Rps19-deficient erythroid precursors and decreased heme levels in a disease-specific manner. HRI heterozygosity, but not A1M treatment, also decreased the elevated p53 activity observed in Rps19-deficient cells, indicating that p53 activation is caused by ribosomal stress and aberrant mRNA translation and not heme overload in Rps19-deficiency. Together, these findings suggest that targeting elevated heme levels is a promising new treatment strategy for DBA., (Copyright © 2021. Published by Elsevier Inc.)

Diamond-Blackfan anemia (DBA) is an inherited bone marrow failure syndrome, characterized as a rare congenital bone marrow erythroid hypoplasia (OMIM#105650). Erythroid defect in DBA results in erythroblastopenia in bone marrow as a consequence of maturation blockade between the burst forming unit-erythroid and colony forming unit-erythroid developmental stages, leading to moderate to severe usually macrocytic aregenerative (<20 × 109/L of reticulocytes) anemia. Congenital malformations localized mostly in the cephalic area and in the extremities (thumbs), as well as short stature and cardiac and urogenital tract abnormalities, are a feature of 50% of the DBA-affected patients. A significant increased risk for malignancy has been reported. DBA is due to a defect in the ribosomal RNA (rRNA) maturation as a consequence of a heterozygous mutation in 1 of the 20 ribosomal protein genes. Besides classical DBA, some DBA-like diseases have been identified. The relation between the defect in rRNA maturation and the erythroid defect in DBA has yet to be fully defined. However, recent studies have identified a role for GATA1 either due to a specific defect in its translation or due to its defective regulation by its chaperone HSP70. In addition, excess free heme-induced reactive oxygen species and apoptosis have been implicated in the DBA erythroid phenotype. Current treatment options are either regular transfusions with appropriate iron chelation or treatment with corticosteroids starting at 1 year of age. The only curative treatment for the anemia of DBA to date is bone marrow transplantation. Use of gene therapy as a therapeutic strategy is currently being explored., (Copyright © 2021 by The American Society of Hematology.)

Diamond Blackfan anemia (DBA) is a rare congenital syndrome presenting primarily as pure red cell aplasia with constitutional abnormalities and cancer predisposition. Established treatment options are corticosteroids, regular erythrocyte transfusions with iron chelation therapy, and hematopoietic stem cell transplantation (HSCT). To date, HSCT is the only definitive curative treatment for the hematological phenotype of DBA, but there is little experience with its use. Given the rarity of the disease and its unique features, an expert panel agreed to draw up a set of recommendations on the use of HSCT in DBA to guide clinical decision-making and practice. The recommendations address indications, pretransplant patient evaluation, donor selection, stem cell sources, conditioning regimens, prophylaxis of rejection and graft versus host disease, and post-transplant follow-up., (© 2021. The Author(s), under exclusive licence to Springer Nature Limited.)

Background and Objectives: The status of red blood cell alloimmunization in patients with constitutional anemias including hemoglobinopathies is not known in Norway. The study objective was to investigate the impact of a strategy based on phenotype-matching for C, c, E, e, K, Jka, Jkb, Fya, Fyb, S and s on alloimmunization., Materials and Methods: We reviewed transfusions of 40 patients retrospectively using the computerized blood bank management system and medical records; including diagnosis, age at start of transfusion therapy, gender, number and age of packed red blood cell units transfused, follow-up time, phenotypes of the donors and patients, antigen-negative patients exposed to antigen-positive packed red blood cell units, transfusion reactions and alloantibody specificities., Results: Forty patients received 5402 packed red blood cell units. Alloimmunization frequency was 20 % for the whole group, being 7%, 25 % and 30 % in patients with sickle cell disease (n = 14), thalassemia (n = 16) and other conditions (n = 10), respectively. The alloantibodies detected were anti-E, -c, -C, -Cw, -K, -Jka and -Lua., Conclusion: Good communication between the clinicians and the transfusion services is essential for successful management of patients with constitutional anemias. Providing full phenotype-matched units was not always possible. Extended pheno-/genotyping before the first transfusion and providing antigen-negative units for antigen-negative patients for at least C, c, E and K in every red cell transfusion would probably have reduced the alloimmunization rate. Non-phenotype-matched transfusions seem to be the main reason for alloimmunization. Finding markers for identifying responders prone to alloimmunization will ensure targeted transfusion strategies., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Background: Diamond-Blackfan anemia is a rare inherited bone marrow failure disease. Typical findings include hypoplastic macrocytic anemia, congenital anomalies, and a predisposition to cancer. The molecular basis of the disease is heterozygous mutations of ribosomal proteins without a strict correlation between genotype and phenotype., Observation: We present 2 cases of Diamond-Blackfan anemia diagnosed during infancy with interesting clinical, molecular, and family characteristics., Conclusions: A thorough evaluation of all family members is imperative to identify possible 'silent carriers' who are those with no physical stigmata and minor or absent hematologic manifestations. New mutations could add in the map of the disease., Competing Interests: The authors declare no conflict of interest., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)

Allogeneic hematopoietic stem cell transplantation (HSCT) is the only curative therapy for the hematologic manifestations of Diamond-Blackfan anemia (DBA). However, data regarding the optimal conditioning regimen for DBA patients are limited. We retrospectively compared the outcomes of DBA patients who underwent HSCT using either myeloablative conditioning (MAC) or reduced-intensity conditioning (RIC) regimens. The patients belonged to a cohort treated at our hospitals between 2000 and 2018. HSCT was performed in 27 of 165 patients (16.4%). The median age at the time of HSCT was 3.6 years. Stem cell sources included bone marrow for 25 patients (HLA-matched sibling donors, n = 5; HLA-mismatched related donors, n = 2; HLA-matched/mismatched unrelated donors, n = 18) or cord blood for 2 patients. MAC or RIC regimens were used in 12 and 15 patients, respectively. Engraftment was successful in all 27 patients who underwent HSCT. Three patients who underwent HSCT using MAC regimens developed sinusoidal obstruction syndrome. The 3-year overall survival (OS) and failure-free survival rates (FFS) post-transplantations were 95.2% and 88.4%, respectively, with no significant differences between MAC and RIC regimens. Our data suggest that HSCTs using RIC regimens are effective and obtain engraftment with excellent OS and FFS for young DBA patients.

Data on stem cell transplantation (SCT) for Diamond-Blackfan Anemia (DBA) is limited. We studied patients transplanted for DBA and registered in the EBMT database. Between 1985 and 2016, 106 DBA patients (median age, 6.8 years) underwent hematopoietic stem cell transplantation from matched-sibling donors (57%), unrelated donors (36%), or other related donors (7%), using marrow (68%), peripheral blood stem cells (20%), both marrow and peripheral blood stem cells (1%), or cord blood (11%). The cumulative incidence of engraftment was 86% (80% to 93%), and neutrophil recovery and platelet recovery were achieved on day +18 (range, 16 to 20) and +36 (range, 32 to 43), respectively. Three-year overall survival and event-free survival were 84% (77% to 91%) and 81% (74% to 89%), respectively. Older patients were significantly more likely to die (hazard ratio, 1.4; 95% confidence interval, 1.06 to 1.23; P < .001). Outcomes were similar between sibling compared to unrelated-donor transplants. The incidence of acute grades II to IV of graft-versus-host disease (GVHD) was 30% (21% to 39%), and the incidence of extensive chronic GVHD was 15% (7% to 22%). This study shows that SCT may represent an alternative therapeutic option for transfusion-dependent younger patients., (Copyright © 2021. Published by Elsevier Inc.)

Objective: In this study, clinico-hematological, genetic and outcome profile of children with BMF was evaluated to delineate the underlying genotype and phenotype., Design: Cases were evaluated as two groups: Group 1 (n = 56; DBA-23, FA-18, DC-2, UBMFS-13) included children with suspected IBMFS based on clinical phenotype and accessible lab investigations and Group 2 (n = 53) included children with IAA treated with IST. Targeted NGS was carried out in a subset of these children (n = 42) and supplemented with WES wherever required., Results: We identified causative mutation in overall 15 of 27 tested children (55.5%) in group 1 and 2 of 15 tested children (13.3%) in group 2. In DBA, a mutation was noted in 50% cases with involvement of RPS 19 (75%) and RPL5 (25%) genes. Phenotypic abnormalities were present in 69.5% and response to steroids in 68.4% of cases at a median follow up of 33 months. In children with IAA, overall response (complete + partial) was present in 51% at a median follow up of 23 months. The 3-year OS and FFS for the cohort of IAA were 68% and 48% respectively. Targeted sequencing could also pick up germline mutations in 50% of UBMFS cases and nearly 19% of IAA cases., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: Diamond-Blackfan anemia (DBA) is an inherited bone marrow failure syndrome characterized by anemia, short stature, congenital anomalies, and cancer predisposition. Most cases are due to mutations in genes encoding ribosomal proteins (RP) leading to RP haploinsufficiency. Effective treatments for the anemia of DBA include chronic red cell transfusions, long-term corticosteroid therapy, or hematopoietic stem cell transplantation. In a small patient series and in animal models, there have been hematologic responses to L-leucine with amelioration of anemia. The study objectives of this clinical trial were to determine feasibility, safety, and efficacy of L-leucine in transfusion-dependent patients with DBA., Procedure: Patients ≥2 years of age received L-leucine 700 mg/m 2 orally three times daily for nine months to determine a hematologic response and any improvement in growth (NCT01362595)., Results: This multicenter, phase I/II study enrolled 55 subjects; 43 were evaluable. There were 21 males; the median age at enrollment was 10.4 years (range, 2.5-46.1 years). No significant adverse events were attributable to L-leucine. Two subjects had a complete erythroid response and five had a partial response. Nine of 25, and 11 of 25, subjects experienced a positive weight and height percentile change, respectively, at the end of therapy., Conclusions: L-leucine is safe, resulted in an erythroid response in 16% of subjects with DBA, and led to an increase in weight and linear growth velocity in 36% and 44% of evaluable subjects, respectively. Further studies will be critical to understand the role of L-leucine in the management of patients with DBA., (© 2020 Wiley Periodicals LLC.)

Background: Genetic anaemias lead us to reflect on the classic 'trolley dilemma', when there are two choices but neither one is satisfactory. Either we do not treat anaemia and the patient suffers from chronic tiredness and fatigue, or we do treat it through blood transfusions, leading to iron overload, which is a quite harmful consequence., Case Presentation: We present the case of a 34-year-old woman with Diamond-Blackfan anaemia (DBA). Bone marrow stem cell transplantation had not been accessible during her childhood, so she had been submitted to monthly blood transfusions throughout her life, leading to a hepatitis C virus infection (which was treated, achieving a sustained virological response when she was 18 years old), and secondary haemochromatosis. Despite chelation therapy, diffuse iron deposition was occurring in multiple organs, markedly in the heart and liver. Her serum ferritin was higher than 21,000 ng/mL and transferrin saturation reached 102%. When she faced heart decompensation, this congestive condition led to an acute liver injury overlapping pre-existing hepatic fibrosis. She progressed to haemodynamic and hepatic failure, with clinical features of acute-on-chronic liver failure (ACLF). Despite therapeutic optimisation, she died of respiratory insufficiency. An autopsy was performed and revealed the macroscopic and microscopic findings of a massive iron deposition in the liver, heart, lungs, spleen, bone marrow, thyroid and adrenal glands. We found marked advance of liver fibrosis (chronic damage), as well as necrosis of hepatocytes in zone 3 of the Rappaport acinus (acute damage), supporting the hypothesis of ACLF. The main feature responsible for acute liver decompensation seemed to be heart insufficiency., Conclusion: This is the first case reporting the sequence: DBA, multiple blood transfusions, secondary haemochromatosis, advanced liver fibrosis, heart failure, ACLF and death. A multidisciplinary team is essential to care for DBA patients, since there is a significant emotional burden related to the disease, which might impair an effective chelation therapy and lead to severe consequences due to iron deposition.

Objectives: The aim of this study was to analyze the outcomes of children with Diamond-Blackfan anemia (DBA) treated in Brazil with hematopoietic cell transplantation (HCT)., Methods: We performed a retrospective analysis of 44 pediatrics patients transplanted between 1990 and 2018. The median age of patients was 5 years, and 57% were male. Twenty-five received their first HCT from an HLA-matched sibling donor (MSD), 12 from a HLA matched unrelated bone marrow donor (MUD 10/10, n = 12) and 7 other HLA mismatched donors (MMD)., Results: After a median follow-up of 4 years, estimate 5-year overall survival (OS) for the entire cohort was 70%, 80% for MSD group, 73% for MUD, and 29% for MMD. Thirty-eight out of the 44 evaluable patients engrafted successfully. Primary and secondary graft failure was observed in five and three patients, respectively. Rates of grade II-IV and III-IV acute graft-versus-host disease (aGVHD) were 25% and 18%, respectively. Nine patients developed chronic GVHD (cGVHD)., Conclusion: Overall survival rates observed after HLA matched donors transplant for DBA were comparable to those reported from higher-income countries and international registries., (© 2020 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Ribosomopathies are a group of rare diseases in which genetic mutations cause defects in either ribosome biogenesis or function, given specific phenotypes. Ribosomal proteins, and multiple other factors that are necessary for ribosome biogenesis (rRNA processing, assembly of subunits, export to cytoplasm), can be affected in ribosomopathies. Despite the need for ribosomes in all cell types, these diseases result mainly in tissue-specific impairments. Depending on the type of ribosomopathy and its pathogenicity, there are many potential therapeutic targets. The present manuscript will review our knowledge of ribosomopathies, discuss current treatments, and introduce the new therapeutic perspectives based on recent research. Diamond-Blackfan anemia, currently treated with blood transfusion prior to steroids, could be managed with a range of new compounds, acting mainly on anemia, such as L-leucine. Treacher Collins syndrome could be managed by various treatments, but it has recently been shown that proteasomal inhibition by MG132 or Bortezomib may improve cranial skeleton malformations. Developmental defects resulting from ribosomopathies could be also treated pharmacologically after birth. It might thus be possible to treat certain ribosomopathies without using multiple treatments such as surgery and transplants. Ribosomopathies remain an open field in the search for new therapeutic approaches based on our recent understanding of the role of ribosomes and progress in gene therapy for curing genetic disorders.

Diamond-Blackfan anemia (DBA) was the first ribosomopathy described and is a constitutional inherited bone marrow failure syndrome. Erythroblastopenia is the major characteristic of the disease, which is a model for ribosomal diseases, related to a heterozygous allelic variation in 1 of the 20 ribosomal protein genes of either the small or large ribosomal subunit. The salient feature of classical DBA is a defect in ribosomal RNA maturation that generates nucleolar stress, leading to stabilization of p53 and activation of its targets, resulting in cell-cycle arrest and apoptosis. Although activation of p53 may not explain all aspects of DBA erythroid tropism, involvement of GATA1/HSP70 and globin/heme imbalance, with an excess of the toxic free heme leading to reactive oxygen species production, account for defective erythropoiesis in DBA. Despite significant progress in defining the molecular basis of DBA and increased understanding of the mechanistic basis for DBA pathophysiology, progress in developing new therapeutic options has been limited. However, recent advances in gene therapy, better outcomes with stem cell transplantation, and discoveries of putative new drugs through systematic drug screening using large chemical libraries provide hope for improvement., (© 2020 by The American Society of Hematology.)

Diamond-Blackfan Anemia (DBA) is a rare inherited form of pure red cell aplasia that usually manifests in infancy or early childhood, and is characterized by normochromic macrocytic anemia and bone marrow erythroblastopenia. The majority of DBA cases are associated with mutations in ribosomal protein genes. Here, we describe a Lebanese girl with RPL5-mutated DBA unresponsive to steroid treatment who died from complications following late hematopoietic stem cell transplantation performed at the age of 15 years.

Diamond-Blackfan anemia (DBA) is a congenital pure red cell aplasia associated with congenital abnormalities and cancer predisposition. Allogeneic hematopoietic stem cell transplantation (HSCT) can correct the hematological phenotype and is indicated in transfusion-dependent patients. In 70 children reported to the German DBA and French HSCT registries, HSCT was performed from 1985 to 2017. Median age at HSCT was 5.5 years (range, 0.9-17.3 years). Two-thirds of patients (64%) were transplanted from a matched sibling donor (MSD), and most procedures were performed after the year 1999 (73%). Primary engraftment was achieved in all patients. One patient developed secondary graft failure. Cumulative incidence of acute graft-versus-host disease (GVHD) was 24% for °II-IV (95% confidence interval [CI], 16% to 37%) and 7% for °III-IV (95% CI, 3% to 17%); cumulative incidence of chronic GVHD was 11% (95% CI, 5% to 22%). The probability of chronic GVHD-free survival (cGFS) was 87% (95% CI, 79% to 95%) and significantly improved over time (<2000: 68% [95% CI, 47% to 89%] vs ≥2000: 94% [95% CI, 87% to 100%], P < .01). cGFS was comparable following HSCT from a MSD and an unrelated donor (UD). Of note, no severe chronic GVHD or deaths were reported following MSD-HSCT after 1999. The difference of cGFS in children transplanted <10 years of age compared with older patients did not reach statistical significance (<10 years: 90% [95% CI, 81% to 99%] vs 10-18 years 78% [95% CI, 58% to 98%]). In summary, these data indicate that HSCT is efficient and safe in young DBA patients and should be considered if a MSD or matched UD is available. HSCT for transfusion dependency only must be critically discussed in older patients., (© 2020 by The American Society of Hematology.)

Background: Diamond-Blackfan anemia is a rare congenital red blood cell aplasia characterized by failed erythropoiesis, congenital abnormalities in up to 50% of patients, growth retardation in up to 30% of patients, and a predisposition to malignancy. Diamond-Blackfan anemia is both clinically and genetically a heterogenous condition ranging from subtle asymptomatic erythroid abnormalities to non-immune hydrops fetalis. Current treatment options include corticosteroid therapy, chronic red blood cell transfusions, and hematopoietic stem cell transplantation with gene therapy receiving recent attention. We report the first documented case of Diamond-Blackfan anemia in a Caucasian girl secondary to a sporadic heterozygous whole gene deletion in RPL35A in South Africa. Limited resources, non-availability of tests, unfamiliarity that comes with rare diseases, an expanded differential diagnosis, and an associated neutropenia led to a delay in the diagnosis of Diamond-Blackfan anemia. This case reminds clinicians of Diamond-Blackfan anemia as a cause of aplastic anemia and highlights the difficulty and obstacles in diagnosing Diamond-Blackfan anemia in resource-limited countries., Case Presentation: We report a case of a 6-week-old Caucasian girl presenting with urosepsis and heart failure secondary to a severe anemia and neutropenia. Limited experience and resources resulted in a delay in diagnosis. Genetic studies later confirmed a heterozygous whole gene deletion of RPL35A. Initial treatment was directed toward correcting the anemia with red blood cell transfusion every 3 to 5 weeks., Conclusion: Diamond-Blackfan anemia is a rare disease that carries significant morbidity and mortality if not diagnosed early and managed appropriately. Limited health resources, patient registries, and specialists as seen in developing countries result in a paucity of knowledge about Diamond-Blackfan anemia in Africa. This case reminds clinicians about Diamond-Blackfan anemia as a cause for anemia in infants, the limitations in making the diagnosis in under-resourced health care systems, and the need for standardized treatment protocols applicable to resource-limited countries.

Background: Iron overload, resulting from blood transfusions in patients with chronic anemias, has historically been controlled with regular deferoxamine, but its parenteral requirement encouraged studies of orally-active agents, including deferasirox and deferiprone. Deferasirox, licensed by the US Food and Drug Administration in 2005 based upon the results of randomized controlled trials, is now first-line therapy worldwide. In contrast, early investigator-initiated trials of deferiprone were prematurely terminated after investigators raised safety concerns. The FDA declined market approval of deferiprone; years later, it licensed the drug as "last resort" therapy, to be prescribed only if first-line drugs had failed. We undertook to evaluate the long-term effectiveness and toxicities of deferiprone and deferasirox in one transfusion clinic., Methods and Findings: Under an IRB-approved study, we retrospectively inspected the electronic medical records of consented iron-loaded patients managed between 2009 and 2015 at The University Health Network (UHN), Toronto. We compared changes in liver and heart iron, adverse effects and other outcomes, in patients treated with deferiprone or deferasirox., Results: Although deferiprone was unlicensed in Canada, one-third (n = 41) of locally-transfused patients had been switched from first-line, licensed therapies (deferoxamine or deferasirox) to regimens of unlicensed deferiprone. The primary endpoint of monitoring in iron overload, hepatic iron concentration (HIC), increased (worsened) during deferiprone monotherapy (mean 10±2-18±2 mg/g; p < 0.0003), exceeding the threshold for life-threatening complications (15 mg iron/g liver) in 50% patients. During deferasirox monotherapy, mean HIC decreased (improved) (11±1-6±1 mg/g; p < 0.0001). Follow-up HICs were significantly different following deferiprone and deferasirox monotherapies (p < 0.0000002). Addition of low-dose deferoxamine (<40 mg/kg/day) to deferiprone did not result in reductions of HIC to <15 mg/g (baseline 20±4 mg/g; follow-up, 18±4 mg/g; p < 0.2) or in reduction in the proportion of patients with HIC exceeding 15 mg/g (p < 0.2). During deferiprone exposure, new diabetes mellitus, a recognized consequence of inadequate iron control, was diagnosed in 17% patients, most of whom had sustained HICs exceeding 15 mg/g for years; one woman died after 13 months of a regimen of deferiprone and low-dose deferasirox. During deferiprone exposure, serum ALT increased over baseline in 65% patients. Mean serum ALT increased 6.6-fold (p < 0.001) often persisting for years. During deferasirox exposure, mean ALT was unchanged (p < 0.84). No significant differences between treatment groups were observed in the proportions of patients estimated to have elevated cardiac iron., Conclusions: Deferiprone showed ineffectiveness and significant toxicity in most patients. Combination with low doses of first-line therapies did not improve the effectiveness of deferiprone. Exposure to deferiprone, over six years while the drug was unlicensed, in the face of ineffectiveness and serious toxicities, demands review of the standards of local medical practice. The limited scope of regulatory approval of deferiprone, worldwide, should restrict its exposure to the few patients genuinely unable to tolerate the two effective, first-line therapies., Competing Interests: Dr. Nancy F. Olivieri led two investigator-initiated trials of deferiprone begun in 1989 (partially funded by Apotex Inc. from 1993) at Toronto’s Hospital for Sick Children and the University of Toronto. In 1995, she identified concerns regarding long-term effectiveness and safety of deferiprone. In 1996, both Toronto trials were terminated abruptly and prematurely, and Dr. Olivieri was threatened with legal remedies should she make concerns public. Dr. Brenda L. Gallie, an independent researcher at The Hospital for Sick Children and the University, was involved directly in all related events over the subsequent decade of legal proceedings. An independent description of the first five years of this controversy provides additional details (Thompson J, Baird P, Downie J. The Olivieri Report: The complete text of the report of the independent committee of inquiry commissioned by the Canadian Association of University Teachers. Toronto: James Lorimer & Co. Publishers; 2001). In 2014, a final settlement respecting all legal matters was mediated between Dr. Olivieri and Apotex. This does not alter the authors' adherence to all PLOS ONE policies on sharing data and materials.

Behfar M, Koochakzadeh L, Yazdanian N, Salajegheh P, Rostami T, Khodayari-Namini N, Ghavamzadeh A, Hamidieh AA. Outcome of allogeneic Hematopoietic Stem Cell Transplantation on Diamond-Blackfan anemia using busulfan-based myeloablative regimen. Turk J Pediatr 2019; 61: 407-412. Allogeneic Hematopoietic Stem Cell Transplantation (allo-HSCT) is the only known curative option for hematologic manifestations of Diamond-Blackfan anemia (DBA) as a rare inherited bone marrow failure syndrome. This treatment may be considered for DBA patients with corticosteroid-resistance, transfusion dependence, and/or progression to severe aplastic anemia or myelodysplastic syndrome (MDS)/ Acute myleloid leukemia (AML). In this prospective study, 10 pediatric DBA patients (age < 15 years) who underwent allo-HSCT from HLA-matched donors using non-TBI myeloablative conditioning regimen (intravenous busulfan and cyclophosphamide ± antithymocyte globulin) during September 2010 to February 2014 are reported. For Graft versus Host Disease (GvHD) prophylaxis cyclosporine A. and a short course of methotrexate were administered. Except one patient who received transplantation from his sibling cord blood, engraftment occurred in all the other patients (9 out of 10) with full donor chimerism ( > 95%). The median neutrophil and platelet engraftment times were 11 (range, 10- 13) days and 23 (range, 15-50) days, respectively. Acute GvHD developed in 7 patients. After a median follow-up of 53.3 months, 8 patients are still alive, of whom 7 patients are disease-free. The other two patients died due to grade III-IV acute GvHD. Our data suggests that allo-HSCT using busulan-based non-TBI myeloablative conditioning regimen could be a long-term effective treatment for DBA patients. Early transplantation especially before having multiple transfusions leading to iron overload, particularly from an HLAmatched sibling donor would be associated with favorable outcomes.

Diamond-Blackfan anaemia (DBA) is a rare inherited marrow failure disorder, characterized by hypoplastic anaemia, congenital anomalies and a predisposition to cancer as a result of ribosomal dysfunction. Historically, treatment is based on glucocorticoids and/or blood transfusions, which is accompanied by significant toxicity and long-term sequelae. Currently, stem cell transplantation is the only curative option for the haematological DBA phenotype. Whereas this procedure has been quite successful in the last decade in selected patients, novel therapies and biological insights are still warranted to improve clinical care for all DBA patients. In addition to paediatric haematologists, other physicians (e.g. endocrinologist, gynaecologist) should ideally be involved in the care of this chronic condition from an early age, to improve lifelong management of haematological and non-haematological symptoms, and screen for DBA-associated malignancies. Here we provide an overview of current knowledge and recommendations for the day-to-day care of DBA patients., (© 2018 The Authors. British Journal of Haematology published by British Society for Haematology and John Wiley & Sons Ltd.)

Diamond-Blackfan anemia (DBA) is a rare congenital hypoplastic anemia characterized by a block in erythropoiesis at the progenitor stage, although the exact stage at which this occurs remains to be fully defined. DBA presents primarily during infancy with macrocytic anemia and reticulocytopenia with 50% of cases associated with a variety of congenital malformations. DBA is most frequently due to a sporadic mutation (55%) in genes encoding several different ribosomal proteins, although there are many cases where there is a family history of the disease with varying phenotypes. The erythroid tropism of the disease is still a matter of debate for a disease related to a defect in global ribosome biogenesis. Assessment of biological features in conjunction with genetic testing has increased the accuracy of the diagnosis of DBA. However, in certain cases, it continues to be difficult to firmly establish a diagnosis. This review will focus on the diagnosis of DBA along with a description of new advances in our understanding of the pathophysiology and treatment recommendations for DBA., Competing Interests: No competing interests were disclosed.No competing interests were disclosed.No competing interests were disclosed.

Diamond-Blackfan anemia (DBA) is a congenital red cell aplasia arising from ribosomal protein (RP) defects. Affected patients present with neonatal anemia, occasional dysmorphism, and cancer predisposition. An anemic newborn was diagnosed with DBA due to RPL5 mutation (c.473&#95;474del, p.K158SfsX26). Refractory anemia required regular transfusions and iron chelation therapy. Pancytopenia occurred at age 16 years. Bone-marrow studies showed myelodysplasia, erythroblastosis, and clonal evolution of del(20)(q11.2q13.3). Severe anemia required transfusions. Del(20q), including the L3MBTL1 gene, is reported to be relevant to the hematological phenotype of Shwachman-Diamond syndrome. A combined defect of RPL5 and L3MBTL1 may contribute to the aberrant erythropoiesis in the present case.

Diamond-Blackfan anemia (DBA) is a severe congenital hypoplastic anemia caused by mutation in a ribosomal protein gene. Major clinical issues concern the optimal management of patients resistant to steroids, the first-line therapy. Hematopoietic stem cell transplantation is indicated in young patients with an HLA-matched unaffected sibling donor, and recent results with matched unrelated donor transplants indicate that these patients also do well. When neither steroids nor a transplant is possible red cell transfusions are required, and iron loading is rapid in some DBA patients, so effective chelation is vital. Also discussed are novel treatments under investigation for DBA., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Diamond-Blackfan anemia (DBA) is a rare inherited bone marrow failure disorder linked predominantly to ribosomal protein gene mutations. Here the European DBA consortium reports novel mutations identified in the RPL15 gene in 6 unrelated individuals diagnosed with DBA. Although point mutations have not been previously reported for RPL15 , we identified 4 individuals with truncating mutations p.Tyr81* (in 3 of 4) and p.Gln29*, and 2 with missense variants p.Leu10Pro and p.Lys153Thr. Notably, 75% (3 of 4) of truncating mutation carriers manifested with severe hydrops fetalis and required intrauterine transfusions. Even more remarkable is the observation that the 3 carriers of p.Tyr81* mutation became treatment-independent between four and 16 months of life and maintained normal blood counts until their last follow up. Genetic reversion at the DNA level as a potential mechanism of remission was not observed in our patients. In vitro studies revealed that cells carrying RPL15 mutations have pre-rRNA processing defects, reduced 60S ribosomal subunit formation, and severe proliferation defects. Red cell culture assays of RPL15 -mutated primary erythroblast cells also showed a severe reduction in cell proliferation, delayed erythroid differentiation, elevated TP53 activity, and increased apoptosis. This study identifies a novel subgroup of DBA with mutations in the RPL15 gene with an unexpected high rate of hydrops fetalis and spontaneous, long-lasting remission., (Copyright © 2018 Ferrata Storti Foundation.)

Introduction: Diamond-Blackfan anemia (DBA) is characterized by hypoplastic anemia, congenital anomalies, and a predisposition for malignancies. Most of our understanding of this disorder stems from molecular studies combined with extensive data input from international patient registries., Objectives: To create an overview of the pediatric DBA population in the Netherlands., Methods: Forty-three patients diagnosed with DBA from all Dutch university pediatric hospitals were included in this study, and their clinical and genetic characteristics were collected from patient records., Results: Congenital malformations were present in 24 of 43 patients (55.8%). An underlying genetic defect was identified in 26 of 43 patients (60.5%), the majority of which were found in the RPS19 gene (12 of 43, 27.9%) with 1 patient carrying a mutation in a novel DBA candidate gene, RPL9. In 31 of 35 (88.6%) patients, an initial response to glucocorticoid treatment was observed. Six patients (14.0%) underwent hematopoietic stem cell transplantation, and eleven patients (11 of 43, 25.6%) became treatment-independent spontaneously., Conclusion: In agreement with previous reports, the Dutch pediatric DBA population is both clinically and genetically heterogeneous. National and international registries, together with more extensive genetic testing, are crucial to increase our understanding of genotype and phenotype correlations of this intriguing disorder., (© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Diamond Blackfan Anemia (DBA) is an inherited erythroid aplasia with onset in childhood. Patients carry heterozygous mutations in one of 19 Ribosomal Protein (RP) genes, that lead to defective ribosome biogenesis and function. Standard treatments include steroids or blood transfusions but the only definitive cure is allogeneic Hematopoietic Stem Cell Transplantation (HSCT). Although advances in HSCT have greatly improved the success rate over the last years, the risk of adverse events and mortality is still significant. Clinical trials employing gene therapy are now in progress for a variety of monogenic diseases and the development of innovative stem cell-based strategies may open new alternatives for DBA treatment as well. In this review, we summarize the most recent progress toward the implementation of new therapeutic approaches for this disorder. We present different DNA- and RNA-based technologies as well as new candidate pharmacological treatments and discuss their relevance and potential applicability for the cure of DBA., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Diamond Blackfan anaemia (DBA) is a congenital bone marrow failure syndrome characterised by selective red cell hypoplasia. DBA is most often due to heterozygous mutations in ribosomal protein (RP) genes that lead to defects in ribosome biogenesis and function and result in ribosomal stress and p53 activation. The molecular mechanisms underlying this pathology are still poorly understood and studies on patient erythroid cells are hampered by their paucity. Here we report that RP-mutated lymphoblastoid cell lines (LCLs) established from DBA patients show defective rRNA processing and ribosomal stress features such as reduced proliferation, decreased protein synthesis, and activation of p53 and its target p21. These phenotypic alterations were corrected by gene complementation. Our data indicate that DBA LCLs could be a useful model for molecular and pharmacological investigations.

Patients with inherited bone marrow failure syndromes (IBMFS), such as Fanconi anemia (FA), dyskeratosis congenita (DC), or Diamond Blackfan anemia (DBA), can have hematologic manifestations cured through hematopoietic cell transplantation (HCT). Subsequent late effects seen in these patients arise from a combination of the underlying disease, the pre-HCT therapy, and the HCT process. During the international consensus conference sponsored by the Pediatric Blood and Marrow Transplant Consortium on late effects screening and recommendations following allogeneic hematopoietic cell transplantation for immune deficiency and nonmalignant hematologic diseases held in Minneapolis, Minnesota in May 2016, a half-day session was focused specifically on the unmet needs for these patients with IBMFS. This multidisciplinary group of experts in rare diseases and transplantation late effects has already published on the state of the science in this area, along with discussion of an agenda for future research. This companion article outlines consensus disease-specific long-term follow-up screening guidelines for patients with IMBFS., (Copyright © 2017 The American Society for Blood and Marrow Transplantation. All rights reserved.)