Beta-thalassemia intermedia due to a complex alpha-globin rearrangement and a heterozygous beta thalassemia mutation.

The alpha-thalassaemia alleles are very frequent in the world's population. The main molecular mechanism is a large deletion with the loss of one or two alpha genes. Another type of rarer abnormality exists: the gain of alpha genes. The consequence of a gain is an overproduction of alpha-globin chains, which aggravates a beta-thalassaemia trait into an intermedia phenotype (non-transfusion-dependent thalassaemia, NTDT). Here, we report the case of a young girl referred for a beta-NTDT with a combination never described in the literature: a heterozygous beta-thalassaemia mutation associated with a copy number gain of the alpha-globin locus and -alpha 3.7 deletion on the same allele.

Thrombosis risk with haemoglobin C trait and haemoglobin C disease: A systematic review.

The thrombotic risk with haemoglobin C trait (HbAC) or haemoglobin C disease (HbCC) is unclear. However, individuals with HbCC have demonstrated chronic haemolysis, higher blood viscosity and altered rheology when compared to individuals with wild-type haemoglobin (HbAA). These physiological alterations may theoretically translate to increased risk of thrombosis; therefore, a systematic literature review was performed to investigate the possible association between HbAC and/or HbCC and thrombosis. Twenty-two studies met inclusion criteria representing 782 individuals with HbAC (n = 694) or HbCC (n = 88). Fifteen studies described the presence/absence of venous thromboembolism (VTE) in patients with HbAC (n = 685) or HbCC (n = 79), while seven studies described patients with HbAC (n = 9) or HbCC (n = 9) and arterial thrombosis. Most (n = 20) studies were case reports or case series; however, two studies suggested a potential increased VTE risk with HbAC compared to HbAA in (i) all patients (OR 2.2, 95% CI: 0.9-5.5) and in (ii) pregnant individuals (RR 3.7, 95% CI 0.9-16). This review is the largest assessment of patients with HbC trait or disease and thrombosis to date; despite its limitations, the findings suggest HbC may be a predisposing risk factor to thrombosis. Prospective cohort studies are warranted to definitively elucidate the risk of thrombosis in this population.

The Danish national haemoglobinopathy screening programme: Report from 16 years of screening in a low-prevalence, non-endemic region.

The Danish national haemoglobinopathy screening programme seeks to determine parental haemoglobinopathy carrier state antenatally. In this retrospective register-based study, we evaluated the 16-year trajectory of this programme, utilising the Danish Red Blood Cell Centre's laboratory database, covering approximately 77% of the Danish population. During the study period, we observed a substantial increase in annual diagnostic examinations performed, from 389 in 2007 to 3030 in 2022. Women constituted 88% of these cases, aligning with the emphasis of the screening programme. Of these, 54% of women of reproductive age (15-40 years) and 10% of women >40 years were specified as pregnant. During our study period, 61 children were born with a severe haemoglobinopathy, out of which 23 children were born from mothers not residing in Denmark during their first trimester thus not included in the screening programme. Prenatal invasive testing was performed for 60 fetuses, identifying 12 with homozygous or compound heterozygous haemoglobinopathy. The Danish haemoglobinopathy screening programme has provided screening, information and reproductive choices for numerous families. During the study period, screening for haemoglobinopathies has been steadily increasing and is expected to continue to increase. Awareness of and adherence to the screening programme is subject of further investigation and optimisation.

Microbiome in sickle cell disease: Pathophysiology and therapeutic insights.

Sickle cell disease (SCD) is a complex genetic blood disorder characterized by abnormal haemoglobin, resulting in sickle-shaped red blood cells. While extensive research has concentrated on the genetic and physiological aspects of SCD, recent studies suggest a potential role of the human microbiome in SCD pathophysiology, adding new dimensions to its understanding. This review synthesizes current knowledge on the microbiome's involvement in SCD, focusing on alterations in the gut microbiome composition and diversity compared to healthy individuals, and their implications for disease pathogenesis. We explore how microbiome changes may contribute to vaso-occlusive crises and other complications, along with the possible associations of specific microbial taxa or markers with disease crises and clinical outcomes. Additionally, we discuss the potential of microbiome-targeted interventions, including probiotics, dietary modifications, and faecal microbiota transplantation, in managing SCD complications and improving patient outcomes. Understanding the intricate relationship between the microbiome and SCD could lead to innovative therapeutic strategies and personalized interventions for better managing the disease. This review underscores the importance of further microbiome research and its integration into holistic SCD care.

Sickle cell disease in Indian tribal population: Findings of a multi-centre Indian SCD registry.

BACKGROUND: Sickle cell disease (SCD) registries provide crucial real-world data on demographics, epidemiology, healthcare, patient outcomes, and treatment efficacy. This paper presents findings from the Indian SCD Registry (ISCDR) on clinical manifestations, crisis episodes, disease management, and healthcare utilization in patients with SCD from 12 primary health centres (PHCs) in six tribal districts of India. METHODS: The ISCDR was introduced along with a three-tier screening process. Its Android-based application incorporates two electronic case report forms for patient data collection over one year. This paper presents a year's data from the ISCDR's 324 patients with SCD. RESULTS: Patients with SCD, aged one to 65 years, exhibited varied clinical manifestations. Most patients (85.2 %) were unaware of their SCD status before enrolling in ISCDR. Moderate to severe anaemia was prevalent (66.05 % and 30.56 %, respectively). Pain was a common complaint (80.86 %; CI: 76.17-85.00), while symptoms of stroke included sudden severe headaches (34.57 %; CI: 29.40-40.02). Common splenic sequestration symptoms included stomach pain (42.90 %; CI: 37.44-48.49) and abdominal tenderness (13.27 %; CI: 9.77-17.46), as a sign. Healthcare utilization was high, with 96.30 % receiving treatment and 83.64 % consuming hydroxyurea. Hospitalization occurred for 38.27 % (CI: 32.95-43.81), and 12.04 % (CI: 8.70-16.09) had blood transfusion during last year. CONCLUSIONS: ISCDR serves as a dynamic digital database on SCD epidemiology, clinical aspects, treatment and healthcare utilization. Notably, many patients lacked prior awareness of their SCD status, underscoring the need for improved awareness and care management. Integrating the registry into the national programme can streamline treatment implementation, prioritize management approaches, and optimize individual benefits.

Pregnancy and assisted reproductive technology use in Australian female transfusion-dependent haemoglobinopathy patients: a 20-year retrospective analysis.

BACKGROUND: In the last few decades, the life expectancy of patients with transfusion-dependent thalassaemia (TDT) and sickle cell disease (SCD) has improved significantly, in part because of improved iron chelation. Fertility challenges and pregnancy complications have historically limited reproductive options in this group; however, improved multi-disciplinary care has made infertility a chronic disease complication requiring attention. Despite this, there are very few reports and no Australian data describing fertility and pregnancy outcomes in this population. AIMS: To identify the rate of assisted reproductive technologies (ART) utilisation in our female transfusion-dependent haemoglobinopathy patients and to establish the nature of maternal and neonatal complications in this cohort. METHODS: A 20-year retrospective analysis (1997-2017) at an Australian centre captured data on conception rates, use of assisted reproductive techniques (ART), and pregnancy and neonatal outcomes in female transfusion-dependent haemoglobinopathy patients. RESULTS: Conception was attempted in 14 women (11 TDT and three SCD) during the study period. A total of 28 pregnancies resulting in 25 live births were recorded. ART supported 13 conceptions. A positive association was not identified between elevated mean serum ferritin and ART use; however, all patients with an established diagnosis of hypogonadotropic hypogonadism (HH) required ART. Maternal complications included gestational diabetes mellitus and post-partum haemorrhage. There were no cardiac complications. Two-thirds of women underwent lower segment caesarean section, with prematurity complicating 20% of births. There were no neonatal or maternal deaths. CONCLUSION: Pregnancy is an achievable goal for women with transfusion-dependent haemoglobinopathies, although the support of ART may be required in a subset of patients.

Sickle cell trait in São Tomé e Príncipe: a population-based prevalence study in women of reproductive age.

BACKGROUND: Sickle Cell Disorder is Africa's most prevalent genetic disease. Yet, it remains a neglected condition, with high mortality under-five, and a lack of population-based studies in the region. This is the first of its kind in São Tomé e Príncipe, aiming to estimate the prevalence of sickle cell trait and other haemoglobin variants in women of reproductive age and its associated factors. METHODS: We conducted a cluster survey in 35 neighbourhoods. Haemoglobin was assessed through point-of-care capillary electrophoresis or high-performance liquid chromatography, and sociodemographic data through questionnaires. The weighted prevalence of sickle cell trait (HbAS) and HbC carriers was estimated with a 95% confidence interval (95% CI). We calculated weighted prevalence ratios (95% CI) through robust Poisson regression for its association with age and individual and collective genetic heritage. FINDINGS: The prevalence of sickle cell trait in women of reproductive age in São Tomé e Príncipe (n = 376) was 13.45% (95% CI: 9.05-19.00). The prevalence of HbC carriers was 8.00% (95% CI: 4.71-12.00). Older age and speaking Forro or Angolar were positively associated with having sickle cell trait. INTERPRETATION: The prevalence of sickle cell trait in São Tomé e Príncipe ranks high in the West African region. The country should follow international guidelines, implementing newborn screening and comprehensive healthcare management.

The Importance of Molecular Biological Analysis for the Laboratory Diagnostic of Homozygous Haemoglobin Malay.

Haemoglobin (Hb) Malay is variant haemoglobin with a ß++ thalassemia phenotype. The prevalence of Hb Malay in the Malaysian population was 5.5%. We describe a 58-year-old male who presented with symptomatic anaemia to the Hospital Universiti Sains Malaysia. Further history revealed that the patient had anaemia since the age of 28, and on regular follow-up at other hospital. Physical examination revealed pallor, jaundice and hepatosplenomegaly. The full blood count and peripheral blood smear showed hypochromic microcytic anaemia with anisopoikilocytosis, and many target cells. High-performance liquid chromatography results showed a ß thalassemia trait. However, the diagnosis does not alight with the patient's condition. Bone marrow aspirate was completed and showed reactive changes and erythroid hyperplasia. A molecular test was then performed for ß globin gene mutation detection using Multiplex Amplification Refractory Mutation System (M-ARMS) PCR method. This revealed the result as homozygous codon 19 mutation or Hb Malay. Therefore, in this case report we would like to highlight the laboratory approaches, the challenges faced by the usual haematological investigations and the importance role of molecular testing in the diagnosis of severe anaemia.

Significant haemoglobinopathies: A guideline for screening and diagnosis: A British Society for Haematology Guideline: A British Society for Haematology Guideline.

Antenatal screening/testing of pregnant women should be carried out according to the guidelines of the National Health Service (NHS) Sickle Cell and Thalassaemia Screening Programme. Newborn screening and, when necessary, follow-up testing and referral, should be carried out according to the guidelines of the NHS Sickle Cell and Thalassaemia Screening Programme. All babies under 1 year of age arriving in the United Kingdom should be offered screening for sickle cell disease (SCD). Preoperative screening for SCD should be carried out in patients from ethnic groups in which there is a significant prevalence of the condition. Emergency screening with a sickle solubility test must always be followed by definitive analysis. Laboratories performing antenatal screening should utilise methods that are capable of detecting significant variants and are capable of quantitating haemoglobins A2 and F at the cut-off points required by the national antenatal screening programme. The laboratory must ensure a provisional report is available for antenatal patients within three working days from sample receipt.

Enhanced IgG immune response to COVID-19 vaccination in patients with sickle cell disease.

Patients with sickle cell disease (SCD) are considered to be immunocompromised, yet data on the antibody response to SARS-CoV-2 vaccination in SCD is limited. We investigated anti-SARS-CoV-2 IgG titres and overall neutralizing activity in 201 adults with SCD and demographically matched non-SCD controls. Unexpectedly, patients with SCD generate a more robust and durable COVID-19 vaccine IgG response compared to matched controls, though the neutralizing activity remained similar across both cohorts. These findings suggest that patients with SCD achieve a similar antibody response following COVID-19 vaccination compared to the general population, with implications for optimal vaccination strategies for patients with SCD.

Association of haemolysis markers, blood viscosity and microcirculation function with organ damage in sickle cell disease in sub-Saharan Africa (the BIOCADRE study).

Sickle cell anaemia (SCA) is a monogenic disease with a highly variable clinical course. We aimed to investigate associations between microvascular function, haemolysis markers, blood viscosity and various types of SCA-related organ damage in a multicentric sub-Saharan African cohort of patients with SCA. In a cross-sectional study, we selected seven groups of adult patients with SS phenotype in Dakar and Bamako based on the following complications: leg ulcer, priapism, osteonecrosis, retinopathy, high tricuspid regurgitant jet velocity (TRV), macro-albuminuria or none. Clinical assessment, echocardiography, peripheral arterial tonometry, laboratory tests and blood viscosity measurement were performed. We explored statistical associations between the biological parameters and the six studied complications. Among 235 patients, 58 had high TRV, 46 osteonecrosis, 43 priapism, 33 leg ulcers, 31 retinopathy and 22 macroalbuminuria, whereas 36 had none of these complications. Multiple correspondence analysis revealed no cluster of complications. Lactate dehydrogenase levels were associated with high TRV, and blood viscosity was associated with retinopathy and the absence of macroalbuminuria. Despite extensive phenotyping of patients, no specific pattern of SCA-related complications was identified. New biomarkers are needed to predict SCA clinical expression to adapt patient management, especially in Africa, where healthcare resources are scarce.

Indian sickle cell disease registry for surveillance and patient management: Development and implementation.

In India, sickle cell disease (SCD) predominantly occurs in indigenous (tribal) people, who are about 104 million. However, screening and diagnosis seldom happen. This situation necessitates developing a comprehensive SCD care model, including a registry. This paper describes the development and implementation of the Indian SCD registry (ISCDR) in six tribal-dominated districts of India. The ISCDR was created in two components-(i) an Android-based mobile/tablet application, (ii) a dashboard/admin panel for patients' data management and retrieval. Data capture involves two electronic case report forms (CRF), that is, the primary form (CRF-1) and the repeat visit form (CRF-2). CRF-1 is completed as soon as the patient is found positive and captures the patient's information, including medical history, diagnosis, symptoms, precipitating factors, hospitalisation history and treatment received. Issues related to quality, security and data-sharing were addressed. After the screening system was functional, ISCDR was initiated. In 12 months, data of 324 SCD patients and 1771 carriers were entered. The study demonstrates the feasibility of establishing an SCD registry in India. It collects systematic longitudinal data on SCD patients, which are essential for programme planning and management. Further, it is feasible to scale up and integrate with other health management databases.

ß-Thalassemia Trait Caused by SUPT5H Defects: Another Case Report.

We identified a novel mutation in the SUPT5H gene in a Chinese female who presented with a ß-thalassemia trait. The substitution of c.193C > T (p.Arg65*) leads to a premature stop codon on residue 65 and could be associated with haploinsufficiency. This variant was inherited from the mother who also had the asymptomatic phenotype of ß-thalassemia trait. Our case further supports the role of SUPT5H as a potential ß-globin chain production-modulating gene.

Integrating artificial intelligence into haematology training and practice: Opportunities, threats and proposed solutions.

There remains a limited emphasis on the use beyond the research domain of artificial intelligence (AI) in haematology and it does not feature significantly in postgraduate medical education and training. This perspective article considers recent developments in the field of AI research in haematology and anticipates the potential benefits and risks associated with its deeper integration into the specialty. Anxiety towards the greater use of AI in healthcare stems from legitimate concerns surrounding data protection, lack of transparency in clinical decision-making, and erosion of the doctor-patient relationship. The specialty of haematology has successfully embraced multiple disruptive innovations. We are at the cusp of a new era of closer integration of AI into routine haematology practice that will ultimately benefit patient care but to harness its benefits the next generation of haematologists will need access to bespoke learning opportunities with input from data scientists.

Saving lives through early diagnosis: the promise and role of point of care testing for sickle cell disease.

Sickle cell disease (SCD) is a devastating and under-recognised global child health issue affecting over 300,000 infants annually, with the highest prevalence in India and sub-Saharan Africa. Most affected infants born in low- and middle-income countries (LMIC) lack access to SCD testing and die from complications in the first years of life without a formal diagnosis. The majority of deaths are preventable with early diagnosis and provision of inexpensive interventions. Despite global recognition of the urgent need, expansion of SCD newborn screening (NBS) programmes beyond the pilot stage has been obstructed by a dependence on an expensive and logistically challenging centralised laboratory testing model. Recently, several point-of-care tests (POCT) for SCD have been developed with promising field validation studies. Here, we summarise the state of POCT for SCD, review barriers and unanswered questions, and discuss optimal strategies for utilising POCT to address the growing global burden of SCD. There is an urgent need to prospectively evaluate the ability of POCT to reduce the morbidity and high early mortality of SCD. To impact a sustainable reduction to this end, it is essential to link a diagnosis with comprehensive SCD care, including wide and affordable access to affordable hydroxycarbamide therapy.

A systematic review on hydroxyurea therapy for sickle cell disease in India.

Background & objectives: Sickle cell disease (SCD) constitutes frequently inherited haemoglobin disorders and poses a significant health burden in India. Hydroxyurea (HU), the most commonly used drug, has shown promising results in the clinical management of SCD. The present systematic review was undertaken to assess the efficacy and toxicity of HU in Indian sickle cell patients. Methods: A systematic review of studies on HU therapy was conducted to identify the application of HU and its outcome(s) across India. PubMed, Scopus and Cochrane Library was used as data sources for various studies on the efficacy and toxicity of HU therapy for treatment for SCD in India published between January 2001 and October 2021. Two authors independently extracted the data on study design, patient characteristics and therapeutic outcomes of HU in order to determine the study quality of the present review. Results: Overall, 14 studies were included for a systematic analysis. Of these 11 were prospective, two cross-sectional and one double-blind randomized controlled trial. Low-dose HU (10 mg/kg/day) was found to reduce the rates of vaso-occlusive crisis and hospitalization as well as decreased the requirement of blood transfusion in SCD patients. The foetal haemoglobin (HbF) level was recorded in 13 (80%) studies all of whom reported an elevation in the HbF levels, with a mean increase in per cent HbF from 15.8 to 21.4 per cent across studies. The common adverse events were reversible, mild-to-moderate cytopenia and anaemia. Interpretation & conclusions: The findings of the present review suggest that there is still insufficient information presently to determine the long-term or major adverse effects on organ damage, fertility as well as pregnancy on the use of HU therapy for SCD. Long-term multi-centric studies are thus required to address these problems.

Hyperhaemolytic transfusion reaction in two ß-thalassaemia major patients: The role of eculizumab.

WHAT IS KNOWN AND OBJECTIVE: Hyperhaemolytic transfusion reactions are rare life-threatening events predominantly affecting patients with haemoglobinopathies. We report two cases in ß-thalassaemia major patients on chronic transfusion therapy and highlight the role of eculizumab in its management. CASE SUMMARY: Patient 1 presented with intravascular haemolysis on day 7 (D7) post-transfusion and responded to treatment with corticosteroids and intravenous immunoglobulin. However, patient 2 presented with severe symptomatic anaemia (D4 post-transfusion) unresponsive to the aforementioned measures. Eculizumab administration led to resolution of the hyperhaemolysis. WHAT IS NEW AND CONCLUSION: We report the successful management of hyperhaemolysis with eculizumab in a ß-thalassemia major patient.

A Novel Tool for the Analysis and Detection of Copy Number Variants Associated with Haemoglobinopathies.

Several types of haemoglobinopathies are caused by copy number variants (CNVs). While diagnosis is often based on haematological and biochemical parameters, a definitive diagnosis requires molecular DNA analysis. In some cases, the molecular characterisation of large deletions/duplications is challenging and inconclusive and often requires the use of specific diagnostic procedures, such as multiplex ligation-dependent probe amplification (MLPA). Herein, we collected and comprehensively analysed all known CNVs associated with haemoglobinopathies. The dataset of 291 CNVs was retrieved from the IthaGenes database and was further manually annotated to specify genomic locations, breakpoints and MLPA probes relevant for each CNV. We developed IthaCNVs, a publicly available and easy-to-use online tool that can facilitate the diagnosis of rare and diagnostically challenging haemoglobinopathy cases attributed to CNVs. Importantly, it facilitates the filtering of available entries based on the type of breakpoint information, on specific chromosomal and locus positions, on MLPA probes, and on affected gene(s). IthaCNVs brings together manually curated information about CNV genomic locations, functional effects, and information that can facilitate CNV characterisation through MLPA. It can help laboratory staff and clinicians confirm suspected diagnosis of CNVs based on molecular DNA screening and analysis.

Using DNA testing for the precise, definite, and low-cost diagnosis of sickle cell disease and other Haemoglobinopathies: findings from Tanzania.

BACKGROUND: Sickle cell disease (SCD) is an important cause of under-five mortality. Tanzania is the 5th country in the world with the highest births prevalence of SCD individuals. Significant advances in the neonatal diagnosis of SCD using rapid point-of-care testing have been made. However genetic confirmation is still required for positive cases, in uncertain cases, in multiply transfused patients, to resolve compound heterozygosity (Hb S/ ß0 Thal or Hb S/ ß+ thal) not uncommon in the coastal regions of East Africa and increasingly also for pre-marital counselling and potentially for future curative approaches such as gene therapy. The currently available DNA tests are prohibitively expensive. Here, we describe an easy-to-use, affordable and accurate ß-globin sequencing approach that can be easily integrated within existing NBS for SCD and other haemoglobinopathies especially in Low- and Middle-income Countries. AIM: To evaluate an affordable DNA technology for the diagnosis of Sickle cell disease and other haemoglobinopathies in a resource-limited setting. METHODS: Laboratory-based validation study was conducted by Muhimbili University of Health and Allied Sciences and the University of Oxford involving sequencing of the entire ß -haemoglobin locus using the Oxford Nanopore MinION platform. A total number of 36 Dried blood spots and whole blood samples were subjected to conventional protein-based methods (isoelectric focusing, HPLC), and/or sequenced by the Sanger method as comparators. RESULTS: Sequencing results for SCD using the MinION were 100% concordant with those from the Sanger method. In addition, the long-read DNA sequencing method enabled the resolution of cases with unusual phenotypes which make up 1% of all children in Tanzania. The cost is £11/ sample for consumables, which is cheaper compared to other sequencing platforms. CONCLUSIONS: This is the first report of a comprehensive single DNA assay as a definitive diagnostic test for SCD and other haemoglobinopathies. The test is fast, precise, accurate and affordable.

Vasculo-toxic and pro-inflammatory action of unbound haemoglobin, haem and iron in transfusion-dependent patients with haemolytic anaemias.

Increasing evidence suggests that free haem and iron exert vasculo-toxic and pro-inflammatory effects by activating endothelial and immune cells. In the present retrospective study, we compared serum samples from transfusion-dependent patients with ß-thalassaemia major and intermedia, hereditary spherocytosis and sickle cell disease (SCD). Haemolysis, transfusions and ineffective erythropoiesis contribute to haem and iron overload in haemolytic patients. In all cohorts we observed increased systemic haem and iron levels associated with scavenger depletion and toxic 'free' species formation. Endothelial dysfunction, oxidative stress and inflammation markers were significantly increased compared to healthy donors. In multivariable logistic regression analysis, oxidative stress markers remained significantly associated with both haem- and iron-related parameters, while soluble vascular cell adhesion molecule 1 (sVCAM-1), soluble endothelial selectin (sE-selectin) and tumour necrosis factor α (TNFα) showed the strongest association with haem-related parameters and soluble intercellular adhesion molecule 1 (sICAM-1), sVCAM-1, interleukin 6 (IL-6) and vascular endothelial growth factor (VEGF) with iron-related parameters. While hereditary spherocytosis was associated with the highest IL-6 and TNFα levels, ß-thalassaemia major showed limited inflammation compared to SCD. The sVCAM1 increase was significantly lower in patients with SCD receiving exchange compared to simple transfusions. The present results support the involvement of free haem/iron species in the pathogenesis of vascular dysfunction and sterile inflammation in haemolytic diseases, irrespective of the underlying haemolytic mechanism, and highlight the potential therapeutic benefit of iron/haem scavenging therapies in these conditions.