The inherited diseases of hemoglobin are an emerging global health burden. Blood. 2010;115:4331-4336. [PMID: 20233970 DOI: 10.1182/blood-2010-01-251348]

Evaluation of Hepatic Iron Overload Using a Contemporary 0.55 T MRI System

BACKGROUND

MRI T2* and R2* mapping have gained clinical acceptance for noninvasive assessment of iron overload. Lower field MRI may offer increased measurement dynamic range in patients with high iron concentration and may potentially increase MRI accessibility, but it is compromised by lower signal-to-noise ratio that reduces measurement precision.

PURPOSE

To characterize a high-performance 0.55 T MRI system for evaluating patients with liver iron overload.

STUDY TYPE

Prospective.

POPULATION

Forty patients with known or suspected iron overload (sickle cell anemia [n = 5], ß-thalassemia [n = 3], and hereditary spherocytosis [n = 2]) and a liver iron phantom.

FIELD STRENGTH/SEQUENCE

A breath-held multiecho gradient echo sequence at 0.55 T and 1.5 T.

ASSESSMENT

Patients were imaged with T2*/R2* mapping 0.55 T and 1.5 T within 24 hours, and 16 patients returned for follow-up exams within 6-16 months, resulting in 56 paired studies. Liver T2* and R2* measurements and standard deviations were compared between 0.55 T and 1.5 T and used to validate a predictive model between field strengths. The model was then used to classify iron overload at 0.55 T.

STATISTICAL TESTS

Linear regression and Bland-Altman analysis were used for comparisons, and measurement precision was assessed using the coefficient of variation. A P-value < 0.05 was considered statistically significant.

RESULTS

R2* was significantly lower at 0.55 T in our cohort (488 ± 449 s^-1 at 1.5 T vs. 178 ± 155 s^-1 at 0.55 T, n = 56 studies) and in the patients with severe iron overload (937 ± 369 s^-1 at 1.5 T vs. 339 ± 127 s^-1 at 0.55 T, n = 23 studies). The coefficient of variation indicated reduced precision at 0.55 T (3.5 ± 2.2% at 1.5 T vs 6.9 ± 3.9% at 0.55 T). The predictive model accurately predicted 1.5 T R2* from 0.55 T R2* (Bland Altman bias = -6.6 ± 20.5%). Using this model, iron overload at 0.55 T was classified as: severe R2* > 185 s^-1 , moderate 81 s^-1  < R2* < 185 s^-1 , and mild 45 s^-1  < R2* < 91 s^-1 .

DATA CONCLUSION

We demonstrated that 0.55 T provides T2* and R2* maps that can be used for the assessment of liver iron overload in patients.

EVIDENCE LEVEL

2 TECHNICAL EFFICACY: Stage 2.

Human m6A-mRNA and lncRNA epitranscriptomic microarray reveal function of RNA methylation in hemoglobin H-constant spring disease

The thalassemia of Hemoglobin H-Constant Spring disease (HbH-CS) is the most common type of Thalassemia in non-transfusion thalassemia. Interestingly, the clinical manifestations of the same genotype of thalassemia can be vastly different, likely due to epigenetic regulation. Here, we used microarray technology to reveal the epigenetic regulation of m⁶A in modifiable diseases and demonstrated a role of BCL2A1 in disease regulation. In this study, we revealed that methylating enzyme writers including METTL16, WTAP, CBLL1, RBM15B, and ZC3H13 displayed low expression and the demethylating enzyme ALKBH5, along with reader proteins including IGF2BP2 and YTHDF3 exhibited high expression. In addition, BCL2A1 was hypo-methylated and showed low expression. We also revealed that the BCL2A1 methylation level and IGF2BP2 expression were negatively correlated. Additionally, the mRNAs expression between ALKBH5 and IGF2BP2 were positively correlated. In HbH-CS, most genes were hypo-methylated. This included BCL2A1, which may play an important role in the process of red blood cell differentiation and development of HbH-CS. Moreover, the mRNA-M⁶A methylation status may be regulated by the demethylating enzyme ALKBH5 via IGF2BP2.

Point-of-care microchip electrophoresis for integrated anemia and hemoglobin variant testing

Anemia affects over 25% of the world's population with the heaviest burden borne by women and children. Genetic hemoglobin (Hb) variants, such as sickle cell disease, are among the major causes of anemia. Anemia and Hb variant are pathologically interrelated and have an overlapping geographical distribution. We present the first point-of-care (POC) platform to perform both anemia detection and Hb variant identification, using a single paper-based electrophoresis test. Feasibility of this new integrated diagnostic approach is demonstrated via testing individuals with anemia and/or sickle cell disease. Hemoglobin level determination is performed by an artificial neural network (ANN) based machine learning algorithm, which achieves a mean absolute error of 0.55 g dL^-1 and a bias of -0.10 g dL^-1 against the gold standard (95% limits of agreement: 1.5 g dL^-1) from Bland-Altman analysis on the test set. Resultant anemia detection is achieved with 100% sensitivity and 92.3% specificity. With the same tests, subjects with sickle cell disease were identified with 100% sensitivity and specificity. Overall, the presented platform enabled, for the first time, integrated anemia detection and hemoglobin variant identification using a single point-of-care test.

Correlates of gallbladder stones among patients with sickle cell disease: A meta-analysis

Sickle cell disorders are the most common hemoglobinopathies worldwide. Clinical variability of sickle cell disease (SCD) and susceptibility to its complications have been attributed to hematologic, genetic, and other influencing factors. This review aimed to provide further summary and analyses of the prevalence and factors associated with cholelithiasis among patients with SCD. A systematic database search was conducted in MEDLINE (PubMed), ScienceDirect, Google Scholar, World Health Organization Virtual Health Library, Cochrane Library databases, and System for Information on Gray Literature in Europe (SIGLE). Pooled prevalence, odds ratio (OR), and standardized mean difference (SMD) with the corresponding 95% confidence interval (CI) were calculated using Comprehensive Meta-Analysis Software version 3.3. A total of 34 studies that fulfilled the eligibility criteria were included in the analyses. The overall prevalence of cholelithiasis among SCD patients was 25.3% (95% CI 19.4-32.3%). The risk of developing cholelithiasis was significantly associated with lower total hemoglobin level (SMD = -0.45; P = 0.002), lower hemoglobin F (HbF) level (SMD = -0.85; P = 0.003), higher total serum bilirubin level (SMD = 1.15; P < 0.001), higher reticulocytes count (SMD = 0.44; P = 0.007), and UDP-glucuronosyltransferase-1A1 enzyme (UGT1A1) promoter polymorphism. This review provides a comprehensive view of the high rate of cholelithiasis and its associated factors in SCD patients.

Professionally responsible management of the ethical and social challenges of antenatal screening and diagnosis of β-thalassemia in a high-risk population

Thalassemias are among the most frequent genetic disorders worldwide. They are an important social and economic strain in high-risk populations. The benefit of β-thalassemia screening programs is growing evident but the capacity to diagnose fetal β-thalassemia exceeds the treatment possibilities and even when treatment before birth becomes feasible, difficult decisions about the relative risks will remain. This paper can be of practical and ethically justified aid when counseling women about screening, diagnosis, and treatment of β-thalassemia. It takes in consideration various social challenges, medical issues such as antenatal screening, preimplantation genetic diagnosis, prenatal diagnosis, non-invasive prenatal testing and prenatal therapy. We also describe the Sardinian experience in applying and promoting high-risk population screening and diagnosis programs and future trends in the management of β-thalassemia.

Haploidentical Allogeneic Stem Cell Transplantation in Sickle Cell Disease: A Systematic Review and Meta-Analysis

Allogeneic hematopoietic stem cell transplantation (SCT) is the sole established curative treatment option for patients with sickle cell disease (SCD). However, a lack of HLA-identical sibling donors is a limiting factor. Haploidentical related donors are a promising donor pool, potentially extending SCT as a curative treatment option to a larger group of patients with no other meaningful treatment options for their severe SCD. In the present study, we aimed to systematically review the results of haploidentical SCT in patients with SCD. A comprehensive search was performed in MEDLINE/PubMed and Embase up to May 2021. Data were extracted by 2 reviewers independently, and the Newcastle-Ottawa Quality Assessment Scale was used to assess the quality of the studies. Fourteen studies met our inclusion criteria. To provide an overview of the results of haploidentical SCT, we grouped the studies into myeloablative conditioning versus nonmyeloablative conditioning as well as into in vitro versus in vivo (ie, with post-transplantation cyclophosphamide) T cell depletion with a subgroup meta-analysis of proportions. All the included studies were observational cohort studies. Only 3 of these studies reported data for both matched sibling donor (MSD) SCT and haploidentical SCT. Based on a comparative meta-analysis of the 3 studies that included both haploidentical and MSD transplantation, graft failure was significantly higher in the haploidentical group than in the MSD group (odds ratio, 5.3; 95% confidence interval [CI], 1.0 to 27.6). Overall survival was not significantly different between the groups. A subgroup meta-analysis of the results of haploidentical SCT showed relatively low overall pooled proportions of graft failure (7%; 95% CI, 2% to 20%), acute graft-versus-host disease (GVHD) (4%; 95% CI, 2% to 12%), and chronic GVHD (11%; 95% CI, 7% to 16%). Overall survival (OS) was high in all the included studies (91%; 95% CI, 85% to 94%). Adjustments to the conditioning regimens, robust pretransplantation and post-transplantation T cell depletion, and improved supportive care have resulted in reduced graft failure and improved OS following haploidentical SCT in patients with SCD. We conclude that the safety of haploidentical SCT in SCD patients has improved significantly, and that this should be considered as a curative option in patients with severe SCD.

Improving outcomes and quality of life for patients with transfusion-dependent β-thalassemia: recommendations for best clinical practice and the use of novel treatment strategies

INTRODUCTION

β-thalassemia is one of the most common inherited monogenic diseases. Many patients are dependent on a lifetime of red blood cell (RBC) transfusions and iron chelation therapy. Although treatments have a significant impact on quality of life (QoL), life expectancy, and long-term health outcomes have improved in recent decades through safer RBC transfusion practices and better iron chelation strategies. Advances in the understanding of the pathology of β-thalassemia have led to the development of new treatment options that have the potential to reduce the RBC transfusion burden in patients with transfusion-dependent (TD) β-thalassemia and improve QoL.

AREAS COVERED

This review provides an overview of currently available treatments for patients with TD β-thalassemia, highlighting QoL issues, and providing an update on current clinical experience plus important practical points for two new treatments available for TD β-thalassemia: betibeglogene autotemcel (beti-cel) gene therapy and the erythroid maturation agent luspatercept, an activin ligand trap.

EXPERT OPINION

Approved therapies, including curative gene therapies and supportive treatments such as luspatercept, have the potential to reduce RBC transfusion burden, and improve clinical outcomes and QoL in patients with TD β-thalassemia. Cost of treatment is, however, likely to be a significant barrier for payors and patients.

Cilostazol-mediated reversion of γ-globin silencing is associated with a high level of HbF production: A potential therapeutic candidate for β-globin disorders

Reversal of fetal hemoglobin (HbF) silencing is an attractive therapeutic intervention for β-thalassemia and sickle cell anemia. The current study proposes the therapeutic of repurposing of cilostazol, an FDA-approved antithrombotic agent, as a promising HbF inducer. Preliminary, we report that cilostazol induced erythroid differentiation and hemoglobinization of human erythroleukemia K562 cells. The erythroid differentiation was accompanied by increased expression of γ-globin mRNA transcripts and HbF production. Cilostazol induced erythroid differentiation and HbF production, without significantly affecting proliferation and viability of hemoglobin producing cells at maximum erythroid inducing concentration. Moreover, we investigated the effect of cilostazol on human β- and γ-globin transgenes in in vivo β-YAC transgenic mice, harboring human β-locus along with β-LCR. A good in vitro correlation was found with substantial up-regulation in fetal globin mRNA; whereas, the β-globin gene expression was not significantly changed. F-cells, analysis in the peripheral blood of cilostazol-treated mice, revealed a significant increase in the F-cells population as compared with sham control groups. Together, these findings support the potential of cilostazol as an HbF inducer, which can be evaluated further to develop a new HbF inducer.

Cell count-based parameters and algorithms for thalassaemia trait screening in the southern Chinese population

INTRODUCTION

Thalassaemia trait (TT) is potential to be missed clinically, especially normocytic thalassaemia. We aimed to establish discriminant functions (DFs) and an algorithm for detecting microcytic or normocytic TT in epidemiological screening.

METHODS

The receiver operating characteristics (ROC) curve analysis was used to determine the diagnostic performance of the proposed formulas in differentiating TT and nonthalassaemia (non-TT). DFs combined the two blood count parameters with the highest performance, based on the area under the curve (AUC) value, into mathematical formulas, using logistic regression. The diagnostic efficacy of DFs was subsequently evaluated in 761 participants, and reliability (including adjusted agreement [AA] and Kappa values) and validity (including sensitivity, specificity, likelihood ratio and Youden's Index) were calculated.

RESULTS

Among microcytic participants, the proposed DFs showed good diagnostic performance (in females: AUC = 0.892 [DF1 = 0.015 × RDW-CV/RBC - 0.096 × RDW-SD/RBC + 1.29], in males: AUC = 0.861 [DF2=-0.025 × RDW-SD/RBC - 0.035 × MCV/RBC + 1.415]). Youden's Index, AA and Kappa values for microcytic TT detection were 0.72, 0.86, and 0.72 and 0.63, 0.81 and 0.63 for females and males, respectively. In normocytic participants with RDW-CV/RBC ≤ 3.54, DF3=-0.38 × MCH-0.02 × MCHC+17.37 achieved AUC = 0.857 in females, whereas DF4 = 0.007 × MCV-0.113 × MCH+2.829 achieved AUC = 0.969 in males. The Youden's Index, AA and Kappa values for the proposed DFs for thalassaemia detection were 0.69, 0.84 and 0.67 in females, 0.76, 0.91 and 0.71 in males, respectively.

CONCLUSION

The proposed DFs performed well in the detection of TT among participants with microcytic and normocytic parameters and could be utilized in epidemiological study for TT.

Reactivation of a developmentally silenced embryonic globin gene

The α- and β-globin loci harbor developmentally expressed genes, which are silenced throughout post-natal life. Reactivation of these genes may offer therapeutic approaches for the hemoglobinopathies, the most common single gene disorders. Here, we address mechanisms regulating the embryonically expressed α-like globin, termed ζ-globin. We show that in embryonic erythroid cells, the ζ-gene lies within a ~65 kb sub-TAD (topologically associating domain) of open, acetylated chromatin and interacts with the α-globin super-enhancer. By contrast, in adult erythroid cells, the ζ-gene is packaged within a small (~10 kb) sub-domain of hypoacetylated, facultative heterochromatin within the acetylated sub-TAD and that it no longer interacts with its enhancers. The ζ-gene can be partially re-activated by acetylation and inhibition of histone de-acetylases. In addition to suggesting therapies for severe α-thalassemia, these findings illustrate the general principles by which reactivation of developmental genes may rescue abnormalities arising from mutations in their adult paralogues.

Molecular and phenotype characterization of an elongated β-globin variant produced by HBB:C.313delA

INTRODUCTION

β-thalassemia is a severe hereditary hemolytic anemia. Due to the diversity of mutations spectrum, β-thalassemia manifests a highly heterogeneous clinical severity. We noted that a previous report characterized HBB:c.313delA, at the end of exon 2, as a β-thalassemia trait rather than dominant β-thalassemia, the classification given to similar mutations. We further explored the impact of this functional variant on globin structure through larger pedigree analysis and in vitro studies.

METHODS

Hematological analysis and molecular genotyping were conducted on the proband and his family members. We evaluated functional effects of the variant on β-globin gene in the proband's nucleated erythrocytes and transfected HEK-293T cells. Three-dimensional construction of protein structure was carried out in silico to demonstrate amino acid changes.

RESULTS

The thalassemia major proband was identified as a compound heterozygote of HBB:c.313delA and HBB:c.126_129delCTTT. Three family members with heterozygotes of HBB:c.313delA displayed microcytic hypochromic anemia. Molecular characterization demonstrated that the frameshift mutation could give rise to retro-positioning of the termination codon, resulting in an elongated β-globin chain with an extension of 10 amino acids. Clinical phenotype and functional experiments indicated that HBB:c.313delA led to β⁰ -thalassemia phenotype.

CONCLUSION

We concluded that the phenotype of HBB:c.313delA was mainly related to the stability of mutant mRNA, the degradation of mutant proteins, and production of inclusion bodies according to a systematic description of clinical phenotype and a series of molecular experiments.

Benserazide racemate and enantiomers induce fetal globin gene expression in vivo: Studies to guide clinical development for beta thalassemia and sickle cell disease

Increased expression of developmentally silenced fetal globin (HBG) reduces the clinical severity of β-hemoglobinopathies. Benserazide has a relatively benign safety profile having been approved for 50 years in Europe and Canada for Parkinson's disease treatment. Benserazide was shown to activate HBG gene transcription in a high throughput screen, and subsequent studies confirmed fetal hemoglobin (HbF) induction in erythroid progenitors from hemoglobinopathy patients, transgenic mice containing the entire human β-globin gene (β-YAC) and anemic baboons. The goal of this study is to evaluate efficacies and plasma exposure profiles of benserazide racemate and its enantiomers to select the chemical form for clinical development. Intermittent treatment with all forms of benserazide in β-YAC mice significantly increased proportions of red blood cells expressing HbF and HbF protein per cell with similar pharmacokinetic profiles and with no cytopenia. These data contribute to the regulatory justification for development of the benserazide racemate. Additionally, dose ranges and frequencies required for HbF induction using racemic benserazide were explored. Orally administered escalating doses of benserazide in an anemic baboon induced γ-globin mRNA up to 13-fold and establish an intermittent dose regimen for clinical studies as a therapeutic candidate for potential treatment of β-hemoglobinopathies.

The European Medicines Agency Review of Crizanlizumab for the Prevention of Recurrent Vaso-Occlusive Crises in Patients With Sickle Cell Disease

Crizanlizumab is a monoclonal antibody that binds to P-selectin. On October 28, 2020, a conditional marketing authorization valid through the European Union (EU) was issued for crizanlizumab for the prevention of recurrent vaso-occlusive crises (VOCs) in patients with sickle cell disease aged 16 years or older. Crizanlizumab was evaluated in a phase 2, double-blind, placebo-controlled randomized multicenter trial comparing high-dose (5 mg/kg) crizanlizumab, low-dose (2.5 mg/kg) crizanlizumab and placebo in patients with a history of 2-10 VOCs in the previous year. Patients who were receiving concomitant hydroxycarbamide (HC) as well as those not receiving HC were included in the study. The primary endpoint of the trial was the annual rate of sickle cell-related pain crises as adjudicated by a central review committee. High-dose crizanlizumab led to a 45.3% lower median annual rate of sickle cell-related pain crises compared to placebo (P = 0.010), with no statistically significant difference for the low dose. Treatment with high-dose crizanlizumab led to similar incidences of adverse events (AEs), grade 3 AEs, and serious AEs compared to placebo. Most frequently observed AEs that occurred more often in the crizanlizumab arm compared to placebo were infusion related reactions (34.8% versus 21%), arthralgia (18.2% versus 8.1%), diarrhea (10.6% versus 3.2%), and nausea (18.2% versus 11.3%). The aim of this article is to summarize the scientific review of the application leading to regulatory approval in the EU.

Distribution of β-Thalassemia and Other Hemoglobinopathies in Bangladeshi University Students and Ready-Made Garment Workers

Background

The inheritable thalassemia and other structural hemoglobinopathies are prevalent globally. In Bangladesh, there is a scarcity of studies concerning thalassemia and other structural hemoglobinopathies. Hence, the present study investigated the prevalence and distribution of β-thalassemia and other hemoglobinopathies among the university students and ready-made garment (RMG) workers.

Methods

A cross-sectional study was conducted, whereas a total of 989 subjects were selected randomly from 10 garments industries (n=495) and five universities (n=494) for diagnosis and counseling from April 2018 to August 2018. Basic information related to the study and venous blood was collected and subjected to capillary Hb-electrophoresis for each participant.

Results

The present study identified thalassemia carriers and other hemoglobinopathies among 13.6% of the participants (14.1% university students and 13.2% RMG workers). The most common form of hemoglobin formation disorder was the Hb-E trait (10.5%), considering both participants’ groups. Other forms of hemoglobin formation disorders observed were a β-thalassemia trait, Hb-D trait, Hb-E disease, and β-thalassemia major. The hemoglobinopathies were significantly associated with the individuals who had a family history of thalassemia and were not vaccinated against hepatitis B in the total sample. Although not statistically suggestive, the most considerable portion (87.3%) of the carriers was unmarried in the present findings.

Conclusion

The present study findings are anticipated to help the public health authorities by providing novel data (of a neglected cohort, ie, RGM workers), facilitating the upcoming comprehensive national thalassemia prevention programs.

Cascade screening for beta-thalassemia in Pakistan: development, feasibility and acceptability of a decision support intervention for relatives

The government-funded ‘Punjab Thalassaemia Prevention Project’ (PTPP) in Pakistan includes cascade screening for biological relatives of children with beta-Thalassaemia Major (β-TM). However, there is low uptake of cascade screening. This paper presents the (i) development of a paper-based ‘decision support intervention for relatives’ (DeSIRe) to enable PTPP Field Officers to facilitate informed decision making about carrier testing, and (ii) assessment of the feasibility and acceptability of the DeSIRe. The intervention was developed using the International Patient Decision Aids Standards quality criteria and Ottawa Decision Support Framework. Twelve focus groups were conducted (September and October 2020) to explore the views of healthcare professionals (HCPs) and relatives of children with β-TM, in six cities. The focus groups were attended by 117 participants (60 HCPs and 57 relatives). Thematic analysis showed that the DeSIRe was considered acceptable for supporting relatives to make informed decisions about cascade screening, and potentially feasible for use in clinical practice. Suggestions for changing some words, the structure and adding information about how carrier testing relates to consanguineous marriages will enable further development of the DeSIRe. Participants generally welcomed the DeSIRe; however, they highlighted the perceived need to use more directive language, hence showed a cultural preference for directive genetic counselling. The findings highlight challenges for researchers using western theories, frameworks, policies and clinical guidelines to develop decision support interventions for implementation more globally. Future research is needed to evaluate the use of the DeSIRe in routine practice and whether it enables relatives to make informed decisions.

Integrating a problem-solving intervention with routine care to improve psychosocial functioning among mothers of children with sickle cell disease: A randomized controlled trial

OBJECTIVE

To assess the feasibility of a problem-solving skills training intervention in improving psychological outcomes in mothers of infants with sickle cell disease (SCD).

DESIGN AND METHODS

This parallel randomized controlled trial recruited 64 babies with SCD, 6 to 12 months of age, and their mothers. Baseline measurements assessed mothers' coping and problem-solving skills, depression, and parental stress before random assignment to intervention or control groups (n = 32 each). Problem-solving skills intervention was delivered through 6 monthly sessions, when babies attended for routine penicillin prophylaxis. All measurements were repeated for both groups at the end of the intervention period. Intention to treat analysis used repeated measures mixed models with the restricted estimation maximum likelihood approach.

RESULTS

The problem-solving intervention had no significant effect on mothers' problem-solving skills (adjusted treatment effect: -1.69 points (95% CI:-5.62 to 2.25)), coping behaviours (adjusted treatment effect: 0.65 points (95% CI:- -7.13 to 8.41)) or depressive symptoms (adjusted treatment effect: -0.41 (95% CI: -6.00 to 5.19)). It reduced mothers' level of difficulty in managing stressful events by 9.5 points (95% CI (-16.86 to -2.16); effect size: 0.21 SD). In the subgroup of mothers at risk of depression (n = 31 at baseline), the intervention reduced depression scores with treatment effect of 10.4 points (95%CI: -18.83 to -1.88; effect size: 0.67 SD).

CONCLUSION

This problem-solving skills intervention study suggests feasibility and possible efficacy in improving some maternal outcomes. Further refinement and culturally appropriate adaptations of the intervention could lead to stronger effects.

Elevated Hb A2 is Not Always Indicative of β-Thalassemia

Hb A₂ levels are usually high in carriers of β-thalassemia (β-thal). These levels also provide a sensitive marker for the identification of hemoglobin (Hb) variants. In this study, we aimed to examine two patients from two Chinese families who showed elevated Hb A₂ levels but did not show any signs of β-thal. The HBB variants were analyzed using direct sequencing of HBB and in silico prediction analysis. Moreover, the family's genetic history was investigated. We examined two probands from different Chinese families with elevated Hb A₂ levels who were not afflicted with β-thal, although several nucleotide changes were found at codon 81 (CTC>CTA) (HBB: c.246C>A) in Family 1 and a compound heterozygosity for codon 40 (AGG>AAG) (HBB: c.122G>A) and IVS-II-478 (C>A) (HBB: c.316-373C>A) in Family 2. After investigating the genetic history of both families including the β-thal aspect, we found that these mutations were not responsible for the elevated Hb A₂ levels. It is rarely reported that high Hb A₂ level is not indicative of β-thal. In contrast, low or normal Hb A₂ level is always found with β-thal due to other molecular defects that mask their β-thal genotype. Our results highlight the importance of considering the genetic factors related and unrelated to β-thal to improve the accuracy of future genetic counseling.

Genome-based therapeutic interventions for β-type hemoglobinopathies

For decades, various strategies have been proposed to solve the enigma of hemoglobinopathies, especially severe cases. However, most of them seem to be lagging in terms of effectiveness and safety. So far, the most prevalent and promising treatment options for patients with β-types hemoglobinopathies, among others, predominantly include drug treatment and gene therapy. Despite the significant improvements of such interventions to the patient's quality of life, a variable response has been demonstrated among different groups of patients and populations. This is essentially due to the complexity of the disease and other genetic factors. In recent years, a more in-depth understanding of the molecular basis of the β-type hemoglobinopathies has led to significant upgrades to the current technologies, as well as the addition of new ones attempting to elucidate these barriers. Therefore, the purpose of this article is to shed light on pharmacogenomics, gene addition, and genome editing technologies, and consequently, their potential use as direct and indirect genome-based interventions, in different strategies, referring to drug and gene therapy. Furthermore, all the latest progress, updates, and scientific achievements for patients with β-type hemoglobinopathies will be described in detail.

Is Skeletal Muscle Dysfunction a Limiting Factor of Exercise Functional Capacity in Patients with Sickle Cell Disease?

Patients with sickle cell disease (SCD) have reduced functional capacity due to anemia and cardio-respiratory abnormalities. Recent studies also suggest the presence of muscle dysfunction. However, the interaction between exercise capacity and muscle function is currently unknown in SCD. The aim of this study was to explore how muscle dysfunction may explain the reduced functional capacity. Nineteen African healthy subjects (AA), and 24 sickle cell anemia (SS) and 18 sickle cell hemoglobin C (SC) patients were recruited. Maximal isometric torque (Tmax) was measured before and after a self-paced 6-min walk test (6-MWT). Electromyographic activity of the Vastus Lateralis was recorded. The 6-MWT distance was reduced in SS (p < 0.05) and SC (p < 0.01) patients compared to AA subjects. However, Tmax and root mean square value were not modified by the 6-MWT, showing no skeletal muscle fatigue in all groups. In a multiple linear regression model, genotype, step frequency and hematocrit were independent predictors of the 6-MWT distance in SCD patients. Our results suggest that the 6-MWT performance might be primarily explained by anemia and the self-paced step frequency in SCD patients attempting to limit metabolic cost and fatigue, which could explain the absence of muscle fatigue.

Diagnostic Accuracy of HemotypeSC as a Point-of-Care Testing Device for Sickle Cell Disease: Findings from a Southwestern State in Nigeria and Implications for Patient Care in Resource-Poor Settings of sub-Saharan Africa

This study aimed to determine the performance of a rapid, point-of-care testing device (HemotypeSC)™ for diagnosing sickle cell disease (SCD) relative to 2 commonly-used methods compared to DNA polymerase chain reaction (PCR) as the reference standard. The diagnostic performance of (HemotypeSC)™ in diagnosing SCD and determining various other Hb genotypes relative to high performance liquid chromatography (HPLC) and cellulose acetate Hb electrophoresis in alkaline buffer (CAE) was investigated among 156 participants aged 4 to 23 years in Ekiti, Southwest Nigeria. PCR was considered as the reference method/gold standard. The sensitivity and specificity for SS, SC, AS, AC, and AA genotypes by HemotypeSC and HPLC when compared with PCR, were each 100%. Similarly, their positive and negative predictive values were each 100%. However, sensitivity and specificity for identifying these Hb genotypes by CAE were 100, 100, 96.5, 0, 99.2%, and 99, 100, 92.9, 0, 91.7%. Also, CAE did not identify any of the 2 HbAC individuals that were correctly identified by PCR and both HemotypeSC, and HPLC, thus representing 100% HbAC misdiagnosis. In conclusion, this study shows that HemotypeSC has perfect concordance with PCR and 100% accuracy in diagnosing SCD in the population tested. Its ease of use, accuracy and other attributes make it suitable for use in sub-Saharan Africa for rapid determination of Hb genotypes.

Life expectancy and risk factors for early death in patients with severe thalassemia syndromes in South India

In spite of advances in chelation therapy and screening of blood, mortality associated with the most common life-threatening noncommunicable disease of children in India, transfusion-dependent thalassemia (TDT), remains poorly defined. This study aims at estimating death rates and mortality risk factors associated with TDT. The clinical records of 1087 patients from 5 thalassemia centers in India were retrospectively analyzed from 2011 to 2018. Median patient age was 8.5 years, with 107 patients older than 18 years; 656 patients were male and 431 were female. Demographic details and clinical parameters were analyzed at presentation and at last visit. With 41 recorded deaths, actuarial survival at 26.9 years was 50%, and under-5 mortality was 7 times higher than in the general population. Patients with transfusion-transmitted infections (TTIs) had 3.4 times higher risk for death (P = .031). Serum ferritin higher than 4000 ng/dL had 4.6 times higher risk for mortality compared with ferritin lower than 1000 ng/dL (P = .00063). A hemoglobin drop lower than 2 g/dL per week had 7.7 times higher mortality risk compared with a drop of less than 1 g/dL per week (P < .0001). Social determinants (sex, economic status, and distance from center), splenectomy, and even cardiac complications were not associated with higher mortality risk. Main causes of death were infection, iron overload, TTIs, and allo-immunization. Patients who received more than 4 years of adequate care had more than 66% mortality risk reduction (P < .0001). TDT in India continues to result in high mortality. Ineffective transfusion, TTIs, and chelation continue to be the most significant risk factors. Comprehensive care in dedicated day care centers from early age is likely to improve outcomes.

Drug safety in thalassemia: lessons from the present and directions for the future

Introduction: Beta-thalassemia is an autosomal recessive hereditary anemia characterized by reduced or absent β-globin chain synthesis, affecting about 60,000 people peryear. Management for β-thalassemia major includes regular blood transfusions followed by iron chelating therapy and drug targeting ineffective erythropoiesis.Areas covered: The safety of licensed drugs for the management of β-thalassemia is reviewed, using evidence from clinical trials and observational research. Such drugs include the iron chelators and the erythrocyte maturation agent luspatercept. The safety of emerging treatment, such as hydroxyurea and thalidomide is also reviewed.Expert opinion: Beta-thalassemia is arare disease, and is not surprising that there are limited studies investigating the safety of drugs used in this disease. Indeed, although observational studies are the main source of drug safety information in areal-world setting, only eleven studies were identified for iron-chelators and none of these estimated the risk of agiven safety outcome. Future work should aim to better leverage existing sources of real-world datato investigate drug safety in thalassemia.

Diagnostic accuracy of reticulocyte parameters on the sysmex XN 1000 for discriminating iron deficiency anaemia and thalassaemia in Saudi Arabia

INTRODUCTION

Iron deficient erythropoiesis and Thalassaemia are both associated with microcytic erythropoiesis albeit from different pathological mechanisms. Given the high prevalence of Hemoglobinopathies in the Mediterranean region, discriminating these two conditions is important. Several algorithms using conventional red cell indices have been developed to facilitate diagnosis, however, their diagnostic accuracy is low. The new generation haematology analyzers enabled the use of more innovative parameters such as reticulocyte parameters. We aimed to evaluate the diagnostic performance of the reticulocyte parameters on the Sysmex XN 1000 to distinguish between IDA and Thalassemia in our population.

METHODS

We performed a retrospective analysis of blood samples sent to our laboratory for haemoglobin electrophoresis screening. We categorized our cohort into Thalassemia and Iron Deficient patients based on known diagnostic criteria. We analyzed the reticulocyte parameters using receiver operator curve analysis (ROC) and determined the cut off value for each parameter.

RESULTS

Reticulocyte parameters most accurate for discriminating IDA from Thalassemia patients was: RET, RET-HE and IRF. The RET-HE had the best statistical significance for IDA patients with AUC = 0.69 for cut off 22.25. The RET-HE for dual positive patients was more accurate with AUC = 0.78 for cut off 21.25. The IRF had the best statistical significance for Alpha Thalassemia with AUC = 0.66 for cut off value 18.

CONCLUSION

An IRF cut off below 15.5 and RET-HE cut off below 22.25 was the most accurate variable in predicting IDA with a sensitivity of 59.4% and 68.3%.

Oxidative status in the β-thalassemia syndromes in Sri Lanka; a cross-sectional survey

In the β-thalassemias, oxidative stress, resulting from chronic hemolysis, globin chain imbalance, iron overload and depleted antioxidant defences, likely contributes to cell death, organ damage, anemia, hypoxia and inflammation. We assessed variations in these parameters in β-thalassemia syndromes in Sri Lanka. Between November 2017 and June 2018, we assessed children and adults attending two thalassemia centres in Sri Lanka: 59 patients with HbE β-thalassemia, 50 β-thalassemia major, 40 β-thalassemia intermedia and 13 HbS β-thalassemia. Median age was 26.0 years (IQR 15.3-38.8), 101 (62.3%) were female and 152 (93.8%) of Sinhalese ethnicity. Methemoglobin, plasma hemoglobin, heme and ferritin were measured as sources of oxidants; plasma total antioxidant capacity, haptoglobin, hemopexin and vitamins C and E assessed antioxidant status; plasma thiobarbituric acid reactive substances and 8-hydroxy-2'-deoxyguanosine assessed oxidative damage; hemoglobin, plasma erythropoietin and transferrin receptor assessed anemia and hypoxia and plasma interleukin-6 and C-reactive protein assessed inflammation. Fruit and vegetable intake was determined by dietary recall. Physical fitness was investigated using the 6-min walk test and measurement of handgrip strength. Oxidant sources were frequently increased and antioxidants depleted, with consequent oxidative damage, anemia, hypoxia and inflammation. Biomarkers were generally most abnormal in HbE β-thalassemia and least abnormal in β-thalassemia intermedia but also varied markedly between individuals with the same thalassemia syndrome. Oxidative stress and damage were also more severe in splenectomized patients and/or those receiving iron chelation therapy. Less than 15% of patients ate fresh fruits or raw vegetables frequently, and plasma vitamins C and E were deficient in 132/160 (82.5%) and 140/160 (87.5%) patients respectively. Overall, physical fitness was poor in all syndromes and was likely due to anemic hypoxia. Studies of antioxidant supplements to improve outcomes in patients with thalassemia should consider individual patient variation in oxidative status both between and within the thalassemia syndromes.

Descriptive analysis of sickle cell patients living in France: The PHEDRE cross-sectional study

Background

Sickle cell disease (SCD) induces chronic haemolytic anaemia and intermittent vaso-occlusion that results in tissue ischaemia causing acute, severe pain episodes that can lead to frequent hospitalizations. These consequences can have repercussions on family, social, school and/or professional life. Here, we present some of the results of the PHEDRE study (Pharmacodépendance Et DREpanocytose—drug dependence and sickle-cell disease), which is the largest study of patients with SCD in France. This paper intends to describe characteristics of the French SCD population. We also aimed to assess the impact of the disease on the lives of patients using objective and subjective variables.

Methods

The PHEDRE study was a national multicentric observational study. Adults, adolescents and children with a confirmed SCD diagnosis were included in the study by their referring doctor. Then, they were interviewed by phone about their socioeconomic status, about the impact of the disease on their lives and about their analgesic and psychoactive drug use.

Results

The study population consisted of 872 patients (28% were minors). Seventy-two percent of adults were active, and all minors were in school. Many patients presented criteria of severe SCD. Seventy-five percent were homozygous SS, 15% were double heterozygotes SC and 8% were heterozygotes Sβthal, 87% received specific treatment, 58% were hospitalized at least once for vaso-occlusive crisis in the past 12 months, and the number of analgesic drugs taken averaged 3.8. Seventy-five percent of patients reported academic or professional consequences related to their SCD, and 52% reported social consequences.

Conclusions

The impact of SCD on patients’ lives can be significant, nevertheless their social integration seems to be maintained. We highlighted respect of recommendations regarding analgesic treatments and only a few patients used tobacco, alcohol or cannabis.

Trial registration

Clinical Trials, NCT02580565; https://clinicaltrials.gov/ Registered 16 October 2015.

Resilience in adolescents with thalassemia

Adolescents with thalassemia often manifest with an increased risk of emotional and behavioral problems, as well as poor quality of life. However, some can be well-adapted and demonstrate evidence of resilience. This study aimed to explore resilience among those with thalassemia and determine the protective factors for their resilience. Sixty adolescents with thalassemia and 60 healthy adolescents as a comparison group participated in the study. Most adolescents with thalassemia demonstrated resilience. Eighty percent of them scored in the low-risk range of the SDQ total difficulties scale, and 91.7% scored in the low-risk range of the SDQ prosocial scale. The mean total difficulties scores of the thalassemia patients and the healthy controls were 11.38 and 11.27 respectively, whereas the mean prosocial scores were 7.28 and 6.65, without statistical significance. Despite the extensive demands of the illness, most adolescents with thalassemia appear to be adapted well, demonstrating evidence of resilience. Factors promoting resilience are lower BMI, less severe type of thalassemia, and younger age at the start of an iron chelator. Health care professionals who take care of adolescents with thalassemia should collaborate to improve their resilience.

Orofacial manifestations of sickle cell disease: implications for dental clinicians

Sickle cell disease is a multisystem disease associated with episodes of acute illness and progressive organ damage. It is one of the most common severe monogenic disorders worldwide and is now the fastest growing genetic disorder in the UK. Dental awareness of orofacial manifestation varies geographically due to the inheritance pattern and patient population affected by the disease. This article details the epidemiology, pathophysiology and the orofacial manifestations in light of current literature.

MOLECULAR MEDICINE: Found in Translation

Studies of the major hemoglobin disorders, β-thalassemia and sickle cell disease (SCD), have laid a foundation for molecular medicine. While enormous progress has been made in understanding gene structure and regulation, translating molecular insights to therapy for the many individuals affected with these disorders has been challenging. Advances in three activities have recently converged to bring novel genetic and potentially curative treatments to clinical trials. First, improved lentiviral vectors for gene transfer into hematopoietic stem cells have revived somatic gene therapy for blood disorders. Second, elucidation of regulatory factors and mechanisms that control the normal developmental switch from fetal to adult hemoglobin has provided a route to reactivation of the fetal form for therapy. Third, revolutionary methods of gene engineering permit molecular insights to be leveraged for patients. Here I review how the promise of molecular medicine to bring transformative treatments to the clinical arena is finally being realized.

A complication risk score to evaluate clinical severity of thalassaemia syndromes

The thalassaemia syndromes (TS) show different phenotype severity. Developing a reliable, practical and global tool to determine disease severity and tailor treatment would be of great value. Overall, 7910 patients were analysed with the aim of constructing a complication risk score (CoRS) to evaluate the probability of developing one or more complications. Nine independent variables were included in the investigation as predictors. Logistic regression models were used for Group A [transfusion-dependent thalassaemia (TDT)], Group B [transfused non-TDT (NTDT)] and Group C (non-transfused NTDT). Statistically significant predictors included age (years), haemoglobin levels, hepatic transaminases [alanine aminotransferase (ALT) and aspartate aminotransferase] and left-ventricular ejection fraction (LVEF) for Group A; age (years), age at first chelation (months), ALT and LVEF for Group B; and age (years), mean serum ferritin (SF) levels and LVEF for Group C. The area under the receiver operating characteristic curve was 84·5%, 82·1% and 80·0% for Groups A, Group B and Group C respectively, suggesting the models had good discrimination. Finally, the CoRS for each group was categorised into four risk classes (low, intermediate, high, and very high) using the centiles of its distribution. In conclusion, we have developed a CoRS for TS that can assist physicians in prospectively tailoring patients' treatment.

An Analysis of Racial and Ethnic Backgrounds Within the CASiRe International Cohort of Sickle Cell Disease Patients: Implications for Disease Phenotype and Clinical Research

Millions are affected by sickle cell disease (SCD) worldwide with the greatest burden in sub-Saharan Africa. While its origin lies historically within the malaria belt, ongoing changes in migration patterns have shifted the burden of disease resulting in a global public health concern. We created the Consortium for the Advancement of Sickle Cell Research (CASiRe) to understand the different phenotypes of SCD across 4 countries (USA, UK, Italy, and Ghana). Here, we report the multi-generational ethnic and racial background of 877 SCD patients recruited in Ghana (n = 365, 41.6%), the USA (n = 254, 29%), Italy (n = 81, 9.2%), and the UK (n = 177, 20.2%). West Africa (including Benin Gulf) (N = 556, 63.4%) was the most common geographic region of origin, followed by North America (N = 184, 21%), Caribbean (N = 51, 5.8%), Europe (N = 27, 3.1%), Central Africa (N = 24, 2.7%), and West Africa (excluding Benin Gulf) (N = 21, 2.4%). SCD patients in Europe were primarily West African (73%), European (10%), Caribbean (8%), and Central African (8%). In the USA, patients were largely African American (71%), Caribbean (13%), or West African (10%). Most subjects identified themselves as Black or African American; the European cohort had the largest group of Caucasian SCD patients (8%), including 21% of the Italian patients. This is the first report of a comprehensive analysis of ethnicity within an international, transcontinental group of SCD patients. The diverse ethnic backgrounds observed in our cohort raises the possibility that genetic and environmental heterogeneity within each SCD population subgroup can affect the clinical phenotype and research outcomes.

CYP450 Mediates Reactive Oxygen Species Production in a Mouse Model of β-Thalassemia through an Increase in 20-HETE Activity

Oxidative damage by reactive oxygen species (ROS) is one of the main contributors to cell injury and tissue damage in thalassemia patients. Recent studies suggest that ROS generation in non-transfusion-dependent (NTDT) patients occurs as a result of iron overload. Among the different sources of ROS, the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase family of enzymes and cytochrome P450 (CYP450) have been proposed to be major contributors for oxidative stress in several diseases. However, the sources of ROS in patients with NTDT remain poorly understood. In this study, Hbbth3/+ mice, a mouse model for β-thalassemia, were used. These mice exhibit an unchanged or decreased expression of the major NOX isoforms, NOX1, NOX2 and NOX4, when compared to their C57BL/6 control littermates. However, a significant increase in the protein synthesis of CYP4A and CYP4F was observed in the Hbbth3/+ mice when compared to the C57BL/6 control mice. These changes were paralleled by an increased production of 20-hydroxyeicosatetraenoic acid (20-HETE), a CYP4A and CYP4F metabolite. Furthermore, these changes corroborate with onset of ROS production concomitant with liver injury. To our knowledge, this is the first report indicating that CYP450 4A and 4F-induced 20-HETE production mediates reactive oxygen species overgeneration in Hbbth3/+ mice through an NADPH-dependent pathway.

In utero Therapy for the Treatment of Sickle Cell Disease: Taking Advantage of the Fetal Immune System

Sickle Cell Disease (SCD) is an autosomal recessive disorder resulting from a β-globin gene missense mutation and is among the most prevalent severe monogenic disorders worldwide. Haematopoietic stem cell transplantation remains the only curative option for the disease, as most management options focus solely on symptom control. Progress in prenatal diagnosis and fetal therapeutic intervention raises the possibility of in utero treatment. SCD can be diagnosed prenatally in high-risk patients using chorionic villus sampling. Among the possible prenatal treatments, in utero stem cell transplantation (IUSCT) shows the most promise. IUSCT is a non-myeloablative, non-immunosuppressive alternative conferring various unique advantages and may also offer safer postnatal management. Fetal immunologic immaturity could allow engraftment of allogeneic cells before fetal immune system maturation, donor-specific tolerance and lifelong chimerism. In this review, we will discuss SCD, screening and current treatments. We will present the therapeutic rationale for IUSCT, examine the early experimental work and initial human experience, as well as consider primary barriers of clinically implementing IUSCT and the promising approaches to address them.

Discovery of DS79932728: A Potent, Orally Available G9a/GLP Inhibitor for Treating β-Thalassemia and Sickle Cell Disease

Therapeutic reactivation of the γ-globin genes for fetal hemoglobin (HbF) production is an attractive strategy for treating β-thalassemia and sickle cell disease. It was reported that genetic knockdown of the histone lysine methyltransferase EHMT2/1 (G9a/GLP) is sufficient to induce HbF production. The aim of the present work was to acquire a G9a/GLP inhibitor that induces HbF production sufficiently. It was revealed that tetrahydroazepine has versatility as a side chain in various skeletons. We ultimately obtained a promising aminoindole derivative (DS79932728), a potent and orally bioavailable G9a/GLP inhibitor that was found to induce γ-globin production in a phlebotomized cynomolgus monkey model. This work could facilitate the development of effective new approaches for treating β-thalassemia and sickle cell disease.

Postoperative acute multiple organ failure after hepatectomy in a Nigerian male with sickle cell trait: a case report

Background

Sickle cell disease (SCD) is a monogenic disease characterized by sickle hemoglobin (HbS). Patients homozygous for HbS experience symptoms resulting from sickled erythrocytes no later than adolescence. However, heterozygous HbS carriers, or those with the so-called sickle cell trait (SCT), may undergo surgery without their hemoglobinopathy being known.

Case presentation

A 53-year-old Nigerian male with hepatitis C infection underwent radiofrequency ablation therapy for multiple hepatocellular carcinomas (HCCs) 17 months prior. Follow-up computed tomography (CT) revealed a solitary tumor (3.2 cm) in the medial section of the cirrhotic liver. The Child–Pugh score was five, and the indocyanine green retention rate at 15 min was 17.4%. The nontumorous liver of the medial section accounted for 10% of the total liver volume according to CT volumetry. With the diagnosis of recurrent HCC, left medial sectionectomy was performed under intermittent blood flow occlusion by Pringle’s maneuver. Intraoperative ultrasonography confirmed that hepatic blood flow had been preserved after hepatectomy. However, laboratory tests on postoperative day (POD) 1 revealed severe liver damage: aspartate aminotransferase 9250 IU/L, alanine aminotransferase 6120 IU/L, total bilirubin 2.8 mg/dL, and prothrombin time% 20.9%. The patient’s renal and respiratory functions also deteriorated; therefore, continuous hemodiafiltration and plasma exchange were initiated under mechanical ventilation. Whole-body contrast-enhanced CT showed no apparent ischemia of the remnant liver, but diffuse cerebral infarction was detected. Despite intensive treatments, he died of multiple organ failure on POD 20. The pathological examination of the resected specimen revealed that the intrahepatic peripheral vessels were occluded by sickled erythrocytes. Additionally, chromatographic analysis of hemoglobin detected the presence of abnormal hemoglobin, although microscopic examination of the peripheral blood erythrocytes did not show morphological abnormalities. Based on these findings, we determined that he had SCT and developed vaso-occlusive crisis involving multiple organs just after hepatectomy.

Conclusion

SCD is a rare disease in eastern Asia, but its prevalence is increasing globally. Surgeons should pay increased attention to this disease, especially when performing hepatectomy under blood flow occlusion.

Standardized microfluidic assessment of red blood cell-mediated microcapillary occlusion: Association with clinical phenotype and hydroxyurea responsiveness in sickle cell disease

OBJECTIVES

We present a standardized in vitro microfluidic assay and Occlusion Index (OI) for the assessment of red blood cell (RBC)-mediated microcapillary occlusion and its clinical associations in sickle cell disease (SCD).

METHODS

Red blood cell mediated microcapillary occlusion represented by OI and its clinical associations were assessed for seven subjects with hemoglobin-SC disease (HbSC), 18 subjects with homozygous SCD (HbSS), and five control individuals (HbAA).

RESULTS

We identified two sub-populations with HbSS based on the OI distribution. HbSS subjects with relatively higher OIs had significantly lower hemoglobin levels, lower fetal hemoglobin (HbF) levels, and lower mean corpuscular volume (MCV), but significantly higher serum lactate dehydrogenase levels and absolute reticulocyte counts, compared to subjects with HbSS and lower OIs. HbSS subjects who had relatively higher OIs were more likely to have had a concomitant diagnosis of intrapulmonary shunting (IPS). Further, lower OI associated with hydroxyurea (HU) responsiveness in subjects with HbSS, as evidenced by significantly elevated HbF levels and MCV.

CONCLUSIONS

We demonstrated that RBC-mediated microcapillary occlusion and OI associated with subject clinical phenotype and HU responsiveness in SCD. The presented standardized microfluidic assay may be useful for evaluating clinical phenotype and assessing therapeutic outcomes in SCD, including emerging targeted and curative treatments that aim to improve RBC deformability and microcirculatory health.

A roadmap for the standardization of hemoglobin A2

BACKGROUND

Standardization of laboratory tests can be a long process, and this is the case with regards to the methods used to measure hemoglobin A2 (HbA2), an important marker for beta-thalassemia and other thalassemic conditions. The IFCC standardization project started in 2004, and it took at least 15 years before developing a reference measurement procedure, defining and producing calibrators and certified reference materials.

METHODS

A series of steps have to be undertaken in order to promote the standardization in the field, a process involving a number of stakeholders (manufacturers, scientific societies, national health bodies, laboratory professionals, clinicians). In this work we describe some possible process indicators, in order to assure that the standardization will have internal and external validity and be effective for a long time. These indicators concern the inter-method studies, elaboration of External Quality Assessment Schemes, and the evaluation of the yearly distributions of HbA2 measurements collected in selected laboratories.

RESULTS

Preliminary results are reported concerning the yearly distributions of HbA2, collected in two different locations, and using different analytical methods. Median yearly values were found very constant over the years, but different between methods. On the other side, results obtained on the same specimens using two different techniques, proved that results by capillary electrophoresis in 2 out of the 3 years of observation, were significantly lower than those by HPLC.

CONCLUSION

In this document we report what has been done so far, and what has to be done to achieve the standardization of the measurement of HbA2 worldwide.

The role of haematopoietic stem cell transplantation for sickle cell disease in the era of targeted disease-modifying therapies and gene editing

Sickle cell disease is one of the most common, life-threatening, non-communicable diseases in the world and a major public health problem. Following the implementation of simple preventive and therapeutic modalities, infant mortality has almost been abolished in high-income countries, but only a small amount of progress has been made in improving survival in adulthood. Progressive end-organ damage, partly related to a systemic vasculopathy, is increasingly recognised. With the availability of a variety of novel disease-modifying drugs, gene addition and gene editing strategies, matched sibling donor haematopoietic stem cell transplantation (HSCT) in children (offering an overall survival rate of 95% and an event-free survival rate of 92%), and encouraging outcomes after alternative donor HSCT, the new challenge is to risk stratify patients, revise transplantation indications, and define the best therapeutic approach for each patient. The ultimate challenge will be to enable these advances in low-income and middle-income countries, where disease prevalence is highest and where innovative strategies are most needed.

Epidemiology of Thalassemia in Gulf Cooperation Council Countries: A Systematic Review

Background

Thalassemia has a burden on the healthcare systems of many countries. About 56000 conceptions result in thalassemia, globally.

Objective

To assess the epidemiological profile of thalassemia in the Gulf Cooperation Council (GCC) countries.

Methods

A systematic search was conducted in MEDLINE/PubMed (National Library of Medicine), CINAHL, and Embase. Relevant observational studies reporting the epidemiology of thalassemia among the GCC population were selected. Data on the prevalence, frequency, and complications of thalassemia were extracted. The quality of the retrieved studies was assessed according to the Newcastle-Ottawa Quality Assessment Scale.

Results

Eighteen studies (14 cross-sectional studies, two retrospective observational studies, and two retrospective analysis) with a total of 3343042 participants were included in this systematic review. Of the 18 studies, 11 studies were conducted in Saudi Arabia, two in the Kingdom of Bahrain, one in Kuwait, three in the United Arab Emirates (UAE), and one in Qatar. The prevalence of thalassemia among children below five years of age ranged from 0.25% to 33%, while it was 0.9% in children above five years and from 0.035% to 43.3% among adult thalassemia patients. The most-reported risk factors were consanguineous marriage and high-risk marriage. There was a lack of data regarding mortality rates in thalassemia.

Conclusions

Despite the premarital screening and genetic counseling (PMSGC) program for thalassemia, the incidence of high-risk couple marriages in GCC countries cannot be effectively diminished. This study suggested that the PMSGC program should adopt more attention for the high-risk areas, to enhance the level of consciousness about the hemoglobinopathy diseases and the consequences of consanguinity among the at-risk couple.

Unknown, so also unvalued? Blood donation awareness and attitudes of potential donors of Dutch and African descent

BACKGROUND AND OBJECTIVES

Many Western countries face a shortage of African blood donors, while their specific blood groups are needed to transfuse chronic transfusion patients of similar ethnic background. Blood donation awareness and attitudes greatly impact the decision to become a blood donor, but how they are related and differ across ethnic groups is understudied. This study investigated blood donation awareness and attitudes of individuals of Dutch and African descent in the Netherlands.

MATERIALS AND METHODS

Survey data of 257 African and 152 Dutch non-donors measuring donation awareness (i.e. being familiar with the Dutch blood bank organization and knowing others who donated blood), cognitive (evaluative judgements) and affective (emotional reactions) attitudes were included. t-Tests, chi-square tests, linear and logistic regressions were conducted to study differences and associations between donation awareness and attitudes.

RESULTS

African individuals were less often aware of the Dutch blood bank organization (43%; p < 0·05) or others who donated blood (51%; p < 0·05) than Dutch individuals (55% and 68%, respectively). African individuals had lower cognitive donation attitudes compared with Dutch individuals (p < 0·001), but no differences were found for affective attitudes (p = 0·55). High donation awareness was associated with higher cognitive (p < 0·001) and affective (p < 0·05) donation attitudes among African minorities, but not among Dutch individuals.

CONCLUSION

The lower donation awareness and cognitive attitudes of African minorities should be taken into consideration in donor recruitment. Raising awareness through effective communication strategies might be essential in the donor decision making process of this target group.

Efficacy and safety of oral hydroxyurea in transfusion-dependent β-thalassaemia: a protocol for randomised double-blind controlled clinical trial

INTRODUCTION

Despite being one of the first diseases to be genetically characterised, β-thalassaemia remains a disorder without a cure in a majority of patients. Most patients with β-thalassaemia receive only supportive treatment and therefore have a poor quality of life and shorter life spans. Hydroxyurea, which has shown to induce fetal haemoglobin synthesis in human erythroid cells, is currently recommended for the treatment of sickle cell disease. However, its clinical usefulness in transfusion-dependent β-thalassaemia is unclear. Here, we present a protocol for a randomised double-blind controlled clinical trial to evaluate the efficacy and safety of oral hydroxyurea in transfusion-dependent β-thalassaemia.

METHODS AND ANALYSIS

This single-centre randomised double-blind placebo-controlled clinical trial is conducted at the Thalassaemia Centre of Colombo North Teaching Hospital, Ragama, Sri Lanka. Adult and adolescent patients with haematologically and genetically confirmed transfusion-dependent β-thalassaemia are enrolled and randomised into the intervention or control group. The intervention group receives oral hydroxyurea 10-20 mg/kg daily for 6 months, while the control group receives a placebo which is identical in size, shape and colour to hydroxyurea without its active ingredient. Transfused blood volume, pretransfusion haemoglobin level, fetal haemoglobin percentage and adverse effects of treatment are monitored during treatment and 6 months post-treatment. Cessation or reduction of blood transfusions during the treatment period will be the primary outcome measure. The statistical analysis will be based on intention to treat.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the Ethics Committee of Faculty of Medicine, University of Kelaniya (P/116/05/2018) and the trial is approved by the National Medicinal Regulatory Authority of Sri Lanka. Results of the trial will be disseminated in scientific publications in reputed journals.

TRIAL REGISTRATION NUMBER

SLCTR/2018/024; Pre-results.

δ-Globin Chain Variants Associated with Decreased Hb A2 Levels: A National Reference Laboratory Experience

High prevalence of hemoglobin (Hb) disorders mandates national programs for screening and genetic counseling in many countries. Increased Hb A₂ levels are commonly associated with β-thalassemias, however, various disorders including alteration of δ chains may result in decreased production of Hb A₂, thus hindering the diagnosis of β-thalassemias. The reported data reflect the experience of a large reference laboratory in the United States. In the current study, we have attempted to assess the prevalence and also tried to characterize the identified mutations in the HBD gene resulting in decreased Hb A₂ levels. In our cohort, 1.6% of 6486 patients were found to have Hb A₂ values of <1.9%. Bidirectional sequencing of the HBD gene demonstrated mutations in 20 cases (19.0% of the individuals with decreased Hb A₂). In addition to the previously reported variants, one novel mutation (Hb A₂-Utah or HBD: c.46T>C).

Hereditary haematologic disorders in Najaf province-Iraq

BACKGROUND

Hereditary hematologic disorders (HHDs) originate from genetic factors that cause disruptions of blood homeostasis. The Thalassemia Unit, Najaf province, Iraq, keeps all medical records of all patients with HHD from the Najaf province.

OBJECTIVES

We aimed to conduct an epidemiological study to obtain a comprehensive epidemiological picture concerning sex distribution, and effects of blood groups and consanguinity.

PATIENTS AND METHODS

All registered HHD patients (until May 2019) in the Thalassemia Unit (1033 patients, aged 0.5-65 years old) were included in the study.

RESULTS

The prevalence of HHD in Najaf city is 69.60 per 100,000 population. There are significantly more male than female HHD patients (Male=53.437%, Female=46.563%, p=0.019). The top 3 prevalent HHD are transfusion-dependent thalassemia (36.012%), non-transfusion dependent thalassemia (34.656%), and sickle-β thalassemia disorder (13.746%). The highest percentage of patients were in the centre of Najaf (56.42%), followed by Kufa, Mishkhab, Haidariah, Manathera, and Abbasiya. The distribution of blood groups and Rh factors of HHD patients in the Najaf population was not significantly different from that in the normal population. The consanguinity rate observed in our patients' parents (78.67%) was significantly higher (p<0.0001) as compared with the consanguinity rate in the population (45.8%).

CONCLUSIONS

During the last few years, there was an increase in HHD cases in Najaf city and, therefore, there is an urgent need to increase awareness about the effects of consanguinity marriages on HHD in order to limit the incidence of HHD.

Pre-transplant myeloid and immune suppression, upfront plerixafor mobilization and post-transplant cyclophosphamide: novel strategy for haploidentical transplant in sickle cell disease

Allogenic hematopoietic stem cell transplant is the only curative option for symptomatic sickle cell disease (SCD). HLA haploidentical related donor transplants are associated with high graft failure rates. We conceptualized a novel protocol (APOLLO protocol) using pre-transplant immune and myelosuppression (PTIS) using fludarabine, cyclophosphamide, and dexamethasone followed by augmented John Hopkins protocol by adding thiotepa to conditioning. Twenty-five consecutive patients suffering from symptomatic SCD were enrolled into the study. We added upfront plerixafor to granulocyte colony stimulating factor (GCSF) for mobilization of healthy donors. Graft versus host disease (GvHD) prophylaxis was done using post-transplant cyclophosphamide, sirolimus, and mycophenolate mofetil. Graft failure was not seen in any of our patients. Five patients developed acute grade II/IV GvHD (4 classical acute, 1 late onset), 3 had limited chronic GvHD. Out of 25 evaluable patients, 22 are alive and disease free, making an overall survival (OS) and disease-free survival (DFS) of 88% with a median follow up of 485 days (range 198-802). T-cell-replete haploidentical transplant with PTIS, augmented John Hopkins conditioning and plerixafor based mobilization is a safe and effective way of treating patients suffering from SCD with minimal or no risk of graft failure and acceptable GvHD rates.

A multicenter cross-sectional study of the quality of life and iron chelation treatment satisfaction of patients with transfusion-dependent β-thalassemia, in routine care settings in Western Greece

PURPOSE

To evaluate health-related quality of life (HRQoL) and satisfaction with iron chelation therapy (ICT) of patients with transfusion-dependent β-thalassemia (TDT) managed under routine care conditions.

PATIENTS AND METHODS

This was an observational, multicenter, cross-sectional study conducted in three hospital-based Thalassemia Units of Western Greece. Patients confidentially completed the 36-item short-form (SF-36) and the "satisfaction with ICT" (SICT) instruments to assess HRQoL and ICT satisfaction respectively.

RESULTS

One hundred and thirty-one adult TDT patients [74 female, median (IQR) age: 41 (36-47) years] were enrolled. Eighty patients (61.1%) were receiving parenteral ICT, with or without oral chelators (Group I), whereas 51 (38.9%) were only receiving oral ICT (Group II). The median SF-36 physical component summary and mental component summary scores were 76.3 and 75.7 among Group I, and 76.9 and 74.5 among Group II patients, not differing between the two groups. In their majority, Group I (84.6%) and Group II (92.9%) patients reported preferring oral ICT. Moreover, Group I patients reported greater perceived ICT effectiveness (median SICT score: 4.3 versus 4.2; p = 0.039), whereas patients receiving deferasirox-containing ICT reported higher treatment acceptance (median SICT score: 4.0 versus 3.6, p = 0.038) and greater satisfaction with the burden of their ICT (median SICT score: 4.4 versus 3.9, p = 0.033).

CONCLUSION

TDT patients prefer to receive oral ICT and are more satisfied of the burden of deferasirox-containing ICT, even though those receiving parenteral ICT are more satisfied by the effectiveness of their treatment. No differences in HRQoL were not noted between patients receiving parenteral versus oral ICT.