Spanish registry of hemoglobinopathies and rare anemias (REHem-AR): demographics, complications, and management of patients with β-thalassemia

INTRODUCTION

The increase in the number of patients with hemoglobinopathies in Europe in recent decades highlights the need for more detailed epidemiological information in Spain. To fulfil this need, the Spanish Society of Pediatric Hematology and Oncology (SEHOP) sponsored the creation of a national registry of hemoglobinopathies known as REHem-AR (Spanish Registry of Hemoglobinopathies and Rare Anemias). Data from the transfusion-dependent (TDT) and non-transfusion-dependent (NTDT) β-thalassemia cohorts are described and analyzed.

METHODS

We performed an observational, multicenter, and ambispective study, which included patients of any age with TDT and NTDT, registered up to December 31, 2021.

RESULTS

Among the 1741 patients included, 168 cases of thalassemia were identified (103 TDT and 65 NTDT-patients). Survival at 18 years was 93% for TDT and 100% for NTDT. Regarding management, 80 patients with TDT (77.7%) and 23 patients with NTDT (35.4%) started chelation treatment during follow-up, with deferasirox being the most widely used. A total of 76 patients within the TDT cohort presented at least 1 complication (73.8%), the most frequent being hemosiderosis and osteopenia-osteoporosis. Comparison of both cohorts revealed significant differences in the diagnosis of hepatic hemosiderosis (p = 0.00024), although these were not observed in the case of cardiac iron overload (p = 0.27).

DISCUSSION

Our registry enabled us to describe the management of β thalassemia in Spain and to analyze the morbidity and mortality of the cohorts of patients with TDT and NTDT. Complications related to iron overload in TDT and NTDT account for most of the morbidity and mortality of the disease, which is associated with a considerable social, psychological, and economic impact, although cardiac, osteopathy and endocrinological complications requiring more attention. The convenience and simplicity of online registries make it possible to homogenize variables and periodically update data, thus providing valuable information on these diseases.

Population pharmacokinetics of cyclosporine A in pediatric patients with thalassemia undergoing allogeneic hematopoietic stem cell transplantation

PURPOSE

To establish the population pharmacokinetics (PPK) model of cyclosporine A(CsA) in pediatric patients with thalassemia undergoing allogeneic hematopoietic stem cell transplantation (HSCT), aiming at providing a reference for clinical dose individualization of CsA.

METHODS

Children with thalassemia who underwent allogeneic HSCT were enrolled retrospectively. The PPK structural model and the random variable model of CsA were established on NONMEN. And goodness of fit plots (GOFs), visual predictive check (VPC), and bootstrap and normalized prediction distribution errors (NPDE) were used to evaluate the final model.

RESULTS

A one-compartment model with first-order absorption was employed to fit the base model. A total of 74 pediatric patients and 600 observations of whole blood concentration were included. The final model included weight (WT) in clearance (CL), alongside post-operative day (POD), fluconazole (FLUC), voriconazole (VORI), posaconazole (POSA), and red blood cell count (RBC) significantly. All the model evaluations were passed.

CONCLUSION

In the PPK model based on the pediatric cohort on CsA with thalassemia undergoing allogeneic HSCT, WT, POD, FLUC, VORI, POSA, and RBC were found to be the significant factors influencing CL of CsA. The reliability and robustness of the final model were excellent. It is expected that the PPK model can assist in individualizing dosing strategy clinically.

Growth and endocrinopathies among children with β-Thalassemia major treated at Dubai Thalassemia centre

BACKGROUND

β-Thalassemia major (BTM) is one of the most common hereditary anemias worldwide. Patients suffer from iron overload that results from repeated blood transfusion This in turn leads to multiple organ damage and endocrinopathies. This study aims to assess the prevalence of growth retardation, hypothyroidism, and diabetes mellitus in children and adolescents with BTM treated at Dubai Thalassemia Centre.

METHODS

A total of 105 children and adolescents were included in this retrospective observational study.

RESULTS

39 children and 66 adolescents' data were analyzed. Females composed 51.3% (n = 20) of children and 53.0% (n = 35) of adolescents. Pretransfusion hemoglobin below 9 gm/dl was observed in 10.8% (n = 4) and 10.6% (n = 7) in children and adolescents, respectively. The mean age of menarche was 13.5 years. Among all study participants, 22.6% (n = 14) had normal height velocity whereas 37.1% (n = 23) had reduced height velocity in one year and 40.3% (n = 25) had reduced height velocity in two consecutive years. The proportion of children and adolescents showing reduced height velocity was significantly higher in females compared to the males (90.6% versus 63.3%, respectively, Chi-square = 6.597, p-value = 0.010). Although none of the study participants had diabetes mellitus, 26.1% (n = 12/46) had pre-diabetes. Elevated TSH was observed in 14.7% (n = 5) children and 8.1% (n = 5) adolescents while low FT4 was reported in one child and one adolescent.

CONCLUSION

Of all endocrinopathies seen among children and adolescents with BTM, growth delay remains the main concern for this group of patients. Effective treatment is key to further reducing endocrinopathies. Although the sample size is limited, we postulate that the low percentage of endocrinopathies among children with BTM treated at Dubai thalassemia center and the low level of pretransfusion anemia reflect the effective transfusion and chelation at the center.

Hospital-acquired pneumonia due to Burkholderia cepacia in a thalassemia pregnancy with postoperative eclampsia: A case report

There are limited case reports on individuals infected with Burkholderia cepacia who do not have typical risk factors, particularly pregnant women with beta-thalassemia. A 34-year-old pregnant female with beta-thalassemia trait and hypertension was admitted to the hospital. The patient was diagnosed with eclampsia and underwent a cesarean section. After two days following the surgery, the patient experienced hospitality-acquired pneumonia. B.cepacia was isolated from blood cultures, and antibiotic susceptibility testing indicated sensitivity to trimethoprim/sulfamethoxazole and levofloxacin. The patient responded to antibiotic treatment. These findings highlight the importance of prompt diagnosis and appropriate treatment in managing B.cepacia infections in pregnant beta-thalassemia patients.

Effects on hearing after long-term use of iron chelators in beta-thalassemia: Over twenty years of longitudinal follow-up

OBJECTIVE

The role of iron chelation in causing hearing loss (HL) is still unclear. The present study assessed the prevalence of HL among transfusion-dependent thalassemia (TDT) patients who underwent audiological follow-up over a 20-year period.

METHODS

We retrospectively analyzed clinical records and audiological tests from January 1990 (T0) to December 2022 (T22) of a group of TDT patients who received iron chelation therapy with deferoxamine (DFO), deferiprone (DFP) or deferasirox (DFX), in monotherapy or as part of combination therapy.

RESULTS

A total of 42 adult TDT patients (18 male, 24 female; age range: 41-55 years; mean age: 49.2 ± 3.7 years) were included in the study. At the T22 assessment, the overall prevalence of sensorineural HL was 23.8 % (10/42). When patients were stratified into two groups, with and without ototoxicity, no differences were observed for sex, age, BMI, creatinine level, pre-transfusional hemoglobin, start of transfusions, cardiac or hepatic T2 MRI; only ferritin serum values and duration of chelation were significantly higher (p = 0.02 and p = 0.01, respectively) in patients with hearing impairment in comparison to those with normal hearing.

CONCLUSION

This study with long-term follow-up suggests that iron chelation therapy might induce ototoxicity; therefore, a long and accurate audiological follow-up should be performed in TDT patients.

Prevalence of thalassemia-carrier couples and fertility risk assessment

Thalassemia is a highly prevalent hematologic disease in Guizhou, China. This study aimed to determine the epidemiological characteristics of thalassemia in couples at childbearing age and assess the neonatal risk of thalassemia in this subpopulation. A cohort of 4481 couples at childbearing age were recruited for thalassemia carrier screening by both traditional hematological tests and next-generation sequencing. Of them, 1314 (14.66%) thalassemia carriers were identified, including 857 (9.76%) α-thalassemia, 391 (4.36%) β-thalassemia, and 48 (0.54%) composite α and β-thalassemia. A total of 12 α-globin gene alterations and 16 β-globin mutations were detected, including four novel thalassemia mutations. SEA was the most common α-thalassemia genotype (26.86%), CD41-42 the most common β-thalassemia genotype (36.57%), and αα/- α3.7 + CD41-42 the most common composite α- and β-thalassemia genotype (18.75%). Ethnically, the Zhuang had the highest rate of thalassemia gene carriers among the ethnic groups. Geographically, Qiannan had the highest rate of thalassemia gene carriers. In addition, 38 of the 48 couples with composite α- and β-thalassemia were high-risk thalassemia carriers, and 4 carrying the -SEA/αα gene needed fertility guidance.

Current challenges of blood transfusions in patients with thalassemia in India and future perspectives

The introduction of regular red blood cell transfusions transformed thalassemia major from a fatal childhood disease into a chronic disorder. Thalassemia is highly prevalent in South Asia, including the Indian subcontinent, and blood transfusion remains the cornerstone of management for these patients. But safe blood transfusions still remain a major problem in India. Difficulties in maintaining adequate blood inventory, a lack of a national blood act, and fragmented blood transfusion services are some of the major contributing factors for the delay in blood supply. In most of the blood centers, alloantibody detection facilities and extended red cell antigen typing are unavailable. Awareness is the key to reducing alloimmunization, which limits the effectiveness of transfusions and the potential availability of blood. Patients with thalassemia are also at high risk of transfusion-transmitted infections unless appropriate blood screening is in place. Hence, many patients remain under-transfused, resulting in decreased health and quality-of-life outcomes. Facilities such as leucoreduction and immunohematological monitoring following a blood transfusion are often lacking in India, especially at the sub-district level. Continuous efforts to raise community awareness, regular training of health-care workers, and proper utilization of available resources are essential to ensuring safe blood transfusions for patients with thalassemia. Access to the new treatments at an affordable cost may reduce the blood transfusion burden for thalassemia patients in India.

Application of the magnetic resonance 3D multiecho Dixon sequence for quantifying hepatic iron overload and steatosis in patients with thalassemia

OBJECTIVE

To investigate the feasibility and diagnostic efficacy of a 3D multiecho Dixon (qDixon) research application for simultaneously quantifying the liver iron concentration (LIC) and steatosis in thalassemia patients.

MATERIALS AND METHODS

This prospective study enrolled participants with thalassemia who underwent 3 T MRI of the liver for the evaluation of hepatic iron overload. The imaging protocol including qDixon and conventional T2* mapping based on 2D multiecho gradient echo (ME GRE) sequences respectively. Regions of interest (ROIs) were drawn in the liver on the qDixon maps to obtain R2* and proton density fat fraction (PDFF). The reference R2* value was measured and calculated on conventional T2* mapping using the CMRtools software. Correlation analysis, Linear regression analysis, and Bland-Altman analysis were performed.

RESULTS

84 patients were finally included in this study. The median R2*-ME-GRE was 366.97 (1/s), range [206.68 (1/s), 522.20 (1/s)]. 8 patients had normal hepatic iron deposition, 16 had Insignificant, 42 had mild, 18 had moderate. The median of R2*-qDixon was 376.88 (1/s) [219.33 (1/s), 491.75 (1/s)]. A strong correlation was found between the liver R2*-qDixon and the R2*-ME-GRE (r = 0.959, P < 0.001). The median value of PDFF was 1.76% (1.10%, 2.95%). 8 patients had mild fatty liver, and 1 had severe fatty liver.

CONCLUSION

MR qDixon research sequence can rapidly and accurately quantify liver iron overload, that highly consistent with the measured via conventional GRE sequence, and it can also simultaneously detect hepatic steatosis, this has great potential for clinical evaluation of thalassemia patients.

Perspectives on anemia: Factors confounding understanding of past occurrence

OBJECTIVE

This paper reviews factors confounding the understanding of the past occurrence of anemia. Using the evidence gathered, a framework is presented of ways forward to enable greater confidence in diagnosing acquired anemia in paleopathology, facilitating insights into longer-term perspectives on this globally relevant condition.

RESULTS

To date, porotic lesions have been central to paleopathological investigations of anemia. The fact that porotic bone lesions are omnipresent and have multiple causes but are likely to have a relatively low, age-related frequency in individuals with anemia, a condition that will have been common in past communities, is confounding.

METHODS

Establishing frameworks that move away from porotic lesions is proposed to facilitate higher levels of more accurate anemia diagnoses in paleopathology.

SIGNIFICANCE

Acceptance of the fundamental principle that anemia may be better considered as a condition requiring metric evaluation of bone structures, supplemented by careful consideration of lesions, will advance understanding of acquired anemia in past communities. Such an approach would provide a clear basis for further consideration of congenital conditions causing anemia, such as sickle-cell disease and thalassemia.

LIMITATIONS

This paper simply opens the conversation on the better diagnosis of anemia in paleopathology; it starts the iterative process of achieving some consensus and progress on diagnosing anemia in paleopathology.

SUGGESTIONS FOR FURTHER RESEARCH

Engagement with ideas presented, sharing data and development of metric parameters will assist in identifying the effects of marrow hyperplasia on bone, enabling more robust work on the important topic of anemia.

Could the 3'UTR+101G>C Mutation Detected in Two Sibling Cases Be a Mutation Affecting the Clinical Presentation in Thalassemia Patients?

Due to letter to aditor, there is no abstract.

Retrospective study and implementation of a low-cost LAMP-turbidimetric assay for screening α0-thalassemia (SEA deletion): preventing and controlling Hb Bart's hydrops fetalis syndrome in Thailand

Homozygous α0-thalassemia (SEA deletion) or Hb Bart's hydrops fetalis syndrome is a significant public health issue in Thailand and Southeast Asia. A prevention and control program has been implemented in this region. This study focuses on retrospective laboratory data collected between January 2021 and April 2023 at a single center. Additionally, we developed a low-cost LAMP-turbidimetric assay to propose in the screening strategy. A total of 3,623 samples underwent screening tests (MCV, MCH, and DCIP), including 1,658 couple screenings (84.25%) and 310 single pregnant screenings (15.75%). Negative screenings, which did not require further investigation, were found in 75.51% for couple screenings and 46.58% for single pregnant screenings. At hemoglobin (Hb) analysis identified 129 couples which had fetuses at risk of severe thalassemia, whereas molecular analysis during the retrospective period revealed 210 samples with different genotypes. These remaining samples were validated using the low-cost LAMP-turbidimetric assay to detect α0-thalassemia (SEA deletion). The developed LAMP turbidimetric assay demonstrated a sensitivity and specificity of 100% (36/36 × 100) and 97.7% (170/174 × 100), respectively, when compared with gap-PCR. Furthermore, we propose a strategy involving the addition of the low-cost LAMP-turbidimetric assay before performing the gold standard. This strategy represents a cost-saving of USD 2,608 based on 210 samples that required DNA analysis. Finally, the developed LAMP turbidimetric assays offer advantages such as reduced time, workload, cost savings, no need for highly developed instruments, and a straightforward interpreting process. Therefore, implementation of LAMP assays into routine settings would be improve the efficiency of prevention and control program for severe thalassemia disease in this region.

Psychological challenges and quality of life in Pakistani parents of children living with thalassemia

PURPOSE

Children living with thalassemia experience psychological challenges, but despite significant psychosocial burdens, caregivers' psychological wellbeing and quality of life remain understudied, particularly in lower-and-middle-income countries.

DESIGN AND METHOD

The current study evaluated these relationships in 100 male and female Pakistani caregivers (23-45 years; 61% female) using Ryff's Psychological Well-Being Scale and the Singapore Caregiver Quality of Life Scale. Caregivers completed questionnaires during regularly scheduled clinic visits for their child.

RESULTS

We found that Pakistani caregivers in our sample generally had significantly lower (30-40 points) quality of life than a referent sample of caregivers of older adults (ps < 0.001). Self-acceptance and personal growth were consistently significant predictors across quality of life domains. Further, significant interactions were observed. Female caregivers with less self-acceptance had worse mental health and wellbeing and impact on daily life (p < .05). Male caregivers with less personal growth had worse physical health wellbeing (p < .05).

CONCLUSIONS

Our results demonstrate the importance of considering how distinct aspects of psychological wellbeing, rather than just the overall score, relate to the specific quality of life domains among male and female caregivers.

PRACTICE IMPLICATIONS

Pediatric nurses are at the frontline of service delivery for children and are in a prime position to observe caregivers who could be at high risk for psychological challenges. Given our findings, future clinical interventions should prioritize support services promoting personal growth and self-acceptance for Pakistani caregivers of children living with thalassemia.

Development of preimplantation genetic testing for monogenic reference materials using next-generation sequencing

OBJECTIVE

Preimplantation genetic testing for monogenic disorders (PGT-M) has been used for over 20 years to detect many serious genetic conditions. However, there is still a lack of reference materials (RMs) to validate the test performance during the development and quality control of PGT-M.

METHOD

Sixteen thalassemia cell lines from four thalassemia families were selected to establish the RMs. Each family consisted of parents with heterozygous mutations for α- and/or β-thalassemia and two children, at least one of whom carried a homozygous thalassemia mutation (proband). The RM panel consisted of 12 DNA samples (parents and probands in 4 families) and 4 simulated embryos (cell lines constructed from blood samples from the four nonproband children). Four accredited genetics laboratories that offer verification of thalassemia samples were invited to evaluate the performance of the RM panel. Furthermore, the stability of the RMs was determined by testing after freeze‒thaw cycles and long-term storage.

RESULTS

PGT-M reference materials containing 12 genome DNA (gDNA) reference materials and 4 simulated embryo reference materials for thalassemia testing were successfully established. Next-generation sequencing was performed on the samples. The genotypes and haplotypes of all 16 PGT-M reference materials were concordant across the four labs, which used various testing workflows. These well-characterized PGT-M reference materials retained their stability even after 3 years of storage.

CONCLUSION

The establishment of PGT-M reference materials for thalassemia will help with the standardization and accuracy of PGT-M in clinical use.

Genetic epidemiology of thalassemia in couples of childbearing age: over 6 years of a thalassemia intervention project

BACKGROUND

Shenzhen is one of the most populated metropolises in southern China where thalassemia is highly prevalent. The prevention of thalassemia inheritance is an ambition of child-bearing couples.

METHODS AND RESULTS

A total of 22,098 peripheral blood samples were collected from 11,049 potentially at-risk couples of childbearing age from Shenzhen. Thalassemia mutations were determined by PCR-based flow-through hybridization. The results identified 45.02% of the participants (9948 out of 22,098) as harboring globin gene mutations, distributed into 18 α-thalassemia alleles detected in 71.48% (7111 out of 9948) and 15 β-thalassemia alleles detected in 32.68% (3252 out of 9948) of all mutant individuals, among which 415 individuals carried both α- and β-thalassemia alleles. The most frequent phenotypes for α-globin variations were --SEA/αα (63.37%), -α3.7/αα (18.66%), and -α4.2/αα (7.31%), and those for β-globin variations were β41-42/βN (34.96%), β654/βN (28.11%), and β17/βN (13.84%). A total of 970 high-risk couples who could possibly give birth to offspring with thalassemia intermedia or major were identified. In addition, the hematological indices were compared among thalassemia genotypes. Significant differences in MCH, MCV, Hb A, and Hb A2 levels among α-thalassemia minor (α+), trait (α0), and intermediate phenotypes (P < 0.05) and between βE/βN and the other β-thalassemia phenotypes (P < 0.05) were found. Moreover, GAP-PCR and next-generation sequencing further identified 42 rare mutations, 13 of which were first reported in the Chinese population. A novel mutation in the β-globin gene (HBB: c.246 C > A (rs145669504)) was also discovered.

CONCLUSIONS

This study presented a comprehensive analysis of thalassemia variations in a population from Shenzhen and may offer valuable insights for thalassemia control and intervention strategies in this area.

Genotype analysis of 55,281 cases of thalassemia in northern Guangxi

OBJECTIVE

To understand the genotype and distribution of thalassemia in northern Guangxi.

METHODS

The study subjects were 55,281 individuals who came to the Affiliated Hospital of Guilin Medical University for genetic diagnosis of thalassemia from January 2012 to August 2023. All of their household registration was in the precincts of Guibei District and its affiliated counties. Red blood cell parameters and hemoglobin analysis were used for thalassemia screening. Gap-PCR, PCR-reverse dot blot hybridization (PCR-RDB), and multicolor melting curve analysis (MMCA) were used to identify common thalassemia genes. Multiplex ligation-dependent probe amplification (MLPA), Sanger sequencing, and third-generation single-molecule real-time (SMRT) sequencing were employed to identify rare thalassemia genes.

RESULTS

Among the 55,281 samples, 16,442 (29.74%) were diagnosed with thalassemia. The detection rates of α, β, and α combined β-thalassemia were 18.57%, 9.99% and 1.18%, respectively. Among ethnical groups, allele mutation frequency of thalassemia was the highest in Zhuang (44.97%), followed by Yao (40.11%), Dong (31.33%), Han (29.85%), Miao (24.31%), and Hui (20.6%). A total of 11,659 alleles (21.09%) of 8 types of α-thalassemia were identified in 55,281 samples, primarily --SEA (53.9%), followed by -α3.7 (21.3%), including rare alleles: --THAI (0.45%) and HKαα (0.38%). A total of 6367 (11.52%) and 14 types of β-thalassemia alleles were identified, mainly CD41-42 (50.12%), followed by CD17 (22.22%), including rare alleles: βCD37 (0.16%) and Gγ+ (Aγδβ)0/βN (0.05%). A total of 31 genotypes were detected in 10,264 cases of α-thalassemia, and the main types were --SEA/αα (53.23%), -α3.7/αα (19.15%), and -α4.2/αα (7.21%). A total of 34 genotypes were detected in 5525 cases of β-thalassemia, and the main types were βCD41-42/βN (50.53%), βCD17/βN (21.77%), and βIVS-II-654/βN (12.16%). A total of 78 gene types were detected in 653 cases of α- and β-thalassemia, and the main types were --SEA/αα, βCD41-42/βN (18.68%) and -α3.7/αα, βCD41-42/βN (13.02%). There were 580 cases (5.65%) of HbH disease (α0/α+), and 4 cases of Hemoglobin Bart's Hydrops Foetus syndrome (--SEA/--SEA). In addition, there were 92 cases (1.67%) of intermedia or severe types of β-thalassemia (β0/β0, β0/β+, β+/β+), including 23 cases of combined α-thalassemia. Among the samples screened negative for thalassemia, 3.7% of them were found to carry thalassemia genes, and 91.35% of the genotypes were αWSα/αα, -α3.7/αα, and -α4.2/αα. In addition, 40.26% of αWSα/αα, 22.89% of -α3.7/αα, and 18.51% of -α4.2/αα had no hematological phenotype.

CONCLUSION

The population in northern Guangxi exhibited rich ethnic diversity, with high allelic carrying rates among the Zhuang, Yao and Dong ethnic groups. Thalassemia gene mutations are diverse, encompassing a variety of gene types, with α thalassemia predominating, notably the --SEA/αα gene type. The prevalence of intermedia or severe types of thalassemia is not low, but there are still some carriers of thalassemia in people who are initially tested negative.

Post-transfusion severe headache in a patient with thalassemia with superficial siderosis of the central nervous system: a case report and literature review

BACKGROUND

Patients with severe thalassemia may experience adverse effects from transfusion such as fever, rash, and iron overload after long-term transfusion therapy. Severe headaches as a side effect of blood transfusion in patients with thalassemia are not commonly observed, especially when combined with superficial siderosis of the central nervous system, which is easily misdiagnosed and requires excessive examination and treatment.

CASE PRESENTATION

A 31-year-old woman was admitted with severe headache and vomiting over 3 days following blood transfusion. She was diagnosed with intermediate α-thalassemia at 2 years of age and had a history of irregular blood transfusions. Physical examination revealed horizontal nystagmus with no other abnormal neurological signs. Magnetic resonance (MR) imaging, MR venography, MR arteriography, and cerebrospinal fluid analysis were normal. However, susceptibility-weighted imaging showed abnormal signals in the bilateral and fourth ventricles. Initial antibiotics, antivirals, decompression of intracranial pressure, iron chelation, and symptomatic treatments were administered; subsequently, small intermittent blood transfusions were cautiously administered for severe anemia. The patient's headache was gradually relieved, and she was discharged on day 9. At the 5-month follow-up, the patient's headache recurred following another transfusion.

CONCLUSIONS

Severe post-transfusion headache in patients with thalassemia has not been fully recognized and is easily misdiagnosed, leading to excessive examination and treatment. Understanding the clinical features of transfusion-related headaches can help identify this complication, but the exact pathophysiological mechanism requires further research.

Diagnosis and screening of abnormal hemoglobins

Hemoglobin (Hb) abnormalities, such as thalassemia and structural Hb variants, are among the most prevalent inherited diseases and are associated with significant mortality and morbidity worldwide. However, there were not comprehensive reviews focusing on different clinical analytical techniques, research methods and artificial intelligence (AI) used in clinical screening and research on hemoglobinopathies. Hence the review offers a comprehensive summary of recent advancements and breakthroughs in the detection of aberrant Hbs, research methods and AI uses as well as the present restrictions anddifficulties in hemoglobinopathies. Recent advances in cation exchange high performance liquid chromatography (HPLC), capillary zone electrophoresis (CZE), isoelectric focusing (IEF), flow cytometry, mass spectrometry (MS) and polymerase chain reaction (PCR) etc have allowed for the definitive detection by using advanced AIand portable point of care tests (POCT) integrating with smartphone microscopic classification, machine learning (ML) model, complete blood counts (CBC), imaging-based method, speedy immunoassay, and electrochemical-, microfluidic- and sensing-related platforms. In addition, to confirm and validate unidentified and novel Hbs, highly specialized genetic based techniques like PCR, reverse transcribed (RT)-PCR, DNA microarray, sequencing of genomic DNA, and sequencing of RT-PCR amplified globin cDNA of the gene of interest have been used. Hence, adequate utilization and improvement of available diagnostic and screening technologies are important for the control and management of hemoglobinopathies.

Management of transfusion-dependent β-thalassemia (TDT): Expert insights and practical overview from the Middle East

β-Thalassemia is one of the most common monogenetic diseases worldwide, with a particularly high prevalence in the Middle East region. As such, we have developed long-standing experience with disease management and devising solutions to address challenges attributed to resource limitations. The region has also participated in the majority of clinical trials and development programs of iron chelators and more novel ineffective erythropoiesis-targeted therapy. In this review, we provide a practical overview of management for patients with transfusion-dependent β-thalassemia, primarily driven by such experiences, with the aim of transferring knowledge to colleagues in other regions facing similar challenges.

Clonal hematopoiesis and acquired genetic abnormalities of the red cell: An historical review

Several syndromes affecting the red cell that mimic those induced by germline mutations may result from a somatic mutation that accompanies a myeloid malignancy. These syndromes are most notable in cases of myelodysplastic syndrome, but they are not limited to any one category of myeloid neoplasm. Their occurrence in males exceed the male predominance that is evident in myeloid neoplasms. The syndromes include disorders of globin chain synthesis (α- and β-thalassemia), heme synthesis (erythropoietic porphyria and erythropoietic uroporphyria), red cell membrane structure (elliptocytosis and spherocytosis), red cell enzyme activity (pyruvate kinase deficiency, glucose-6-phosphate dehydrogenase deficiency) and lowered expression of red cell ABO blood group antigens. This historical review describes the path to uncovering these acquired syndromes and their causal somatic mutations, where known. These syndromes often go unrecognized because of the dominant concern of the primary neoplasm. They may add to the healthcare needs of the patient.

Inherited disorders of hemoglobin: A review of old and new diagnostic methods

The genetic regulation of hemoglobin is complex and there are a number of genetic abnormalities that result in clinically important hemoglobin disorders. Here, we review the molecular pathophysiology of hemoglobin disorders and review both old and new methods of diagnosing these disorders. Timely diagnosis of hemoglobinopathies in infants is essential to coordinate optimal life-saving interventions, and accurate identification of carriers of deleterious mutations allows for genetic counseling and informed family planning. The initial laboratory workup of inherited disorders of hemoglobin should include a complete blood count (CBC) and peripheral blood smear, followed by carefully selected tests based on clinical suspicion and available methodology. We discuss the utility and limitations of the various methodologies to fractionate hemoglobin, including cellulose acetate and citrate agar hemoglobin electrophoresis, isoelectric focusing, high-resolution high-performance liquid chromatography, and capillary zone electrophoresis. Recognizing that most of the global burden of hemoglobin disorders exists in low- and middle-income countries, we review the increasingly available array of point-of-care-tests (POCT), which have an increasingly important role in expanding early diagnosis programs to address the global burden of sickle cell disease, including Sickle SCAN, HemoTypeSC, Gazelle Hb Variant, and Smart LifeLC. A comprehensive understanding of the molecular pathophysiology of hemoglobin and the globin genes, as well as a clear understanding of the utility and limitations of currently available diagnostic tests, is essential in reducing global disease burden.

The Prevalence of Pulmonary Arterial Hypertension in Patients with Beta Thalassemia Major

Pulmonary arterial hypertension (PAH) remains a concern in patients with Beta thalassemia major (TM). However, this study aims to investigate the prevalence of PAH in TM patients in Kerman City placed in the south of Iran. In this cross-sectional study on 271 IranianBeta-thalassemia patients (mean age 19.8 ± 7.9 in the range 10-60), Age, sex, weekly deferral taking, the number of blood transfusion in a month, and last echocardiography report data was gathered from every patient's file. SPSS for Windows (version 21) was used for analysis. According to the results, the prevalence of PAH was 10.3% (28 patients). PAH had significant associations with weekly deferral consumption (P = 0.028), ferritin serum level (P = 0.001), and ejection fraction (EF) (P = 0.001). PAH is positively associated with deferral consumption and is negatively associated with EF (respectively, P = 0.031, P = 0.001). It is very important to consider prevention and treatment for decreasing the mortality and morbidity of PAH patients in health planning and policy.

Rational synthesis of FeNiCo-LDH nanozyme for colorimetric detection of deferoxamine mesylate

The accurate surveillance and sensitive detection of deferoxamine mesylate (DFO) is of great significance to ensure the safety of thalassemia major patients. Herein, we report a new nanozyme-based colorimetric sensor platform for DFO detection. First, a metal-organic framework (ZIF-67) was used as a precursor for the synthesis of FeNiCo-LDH (Layered Double Hydroxide, LDH) via an ion exchange reaction stirring at room temperature. The results of electron microscopy and nitrogen adsorption-desorption showed that FeNiCo-LDH exhibited a 3D hollow and mesopores structure, which supplied more exposed active sites and faster transfer of mass. The as-prepared FeNiCo-LDH showed superior peroxidase-like activity with a low Km and high υmax. It can catalyze the decomposition of H2O2 to generate reactive oxygen species (ROS) and further react with 3,3',5,5'-tetramethylbenzidine (TMB) to form blue oxidized TMB (oxTMB), which has a characteristic absorption at 652 nm. Once DFO was introduced, it can complex with FeNiCo-LDH and inhibit the peroxidase-like activity of FeNiCo-LDH, making the color of oxTMB lighter. The quantitative range of DFO was 0.8-28 μM with a detection limit of 0.71 μM. This established method was applied to the detection of DFO content in urine samples of thalassemia patients, and the spiked recoveries were falling between 97.7% and 109.6%, with a relative standard deviation was less than 5%, providing a promising tool for the clinical medication of thalassemia patients.

Comparison of Capillary Zone Electrophoresis with High-pressure Liquid Chromatography in the Evaluation of Hemoglobinopathies

Objective

The capillary zone electrophoresis (CZE) and high-performance liquid chromatography (HPLC) methods were compared in terms of HbA2 measurement for the assessment of hemoglobinopathies.

Materials and Methods

CZE was compared with HPLC for the evaluation of patients without hemoglobinopathy (n=321), with β-thalassemia trait (n=113), and with common (HbD-Punjab, E, C, S/A, and S/S) and rare (HbS/D, O-Arap, Lepore, G-Coushata, Setif, Hamadan, Q-Iran, and H) variants (n=21). The reference range for HbA2 was determined by CZE.

Results

Among patients without hemoglobinopathy, the median (2.5th-97.5th percentiles) values were 97.4% (97.0-98.0%) and 97.5% (96.6-98.4%) for HbA (p=0.060) and 2.4% (1.6-3.0%) and 2.5% (1.6-3.1%) for HbA2 (p<0.001) by HPLC and CZE, respectively. The reference range for HbA2 was 1.6-3.1% by CZE. In the comparison of methods for HbA2, there was a constant error of 0.255 (confidence interval: 0.062-0.448) and bias of 0.10% (limit of agreement: 0.33-0.53), and higher values were obtained with CZE. A strong correlation was observed between the methods (r=0.782). Interrater agreement was almost perfect for clinical diagnosis (ϰ=0.911). The two methods detected and identified the common variants similarly. All rare variants, except HbH by HPLC and HbS/D by CZE, were detected as separate peaks by both methods.

Conclusion

The two methods were in agreement regarding the preliminary identification of β-thalassemia patients. Different Hb variants were detected by both methods but with possible methodological interference for HbA2 measurements. CZE is a reliable and simple alternative for the evaluation of hemoglobinopathies. The standardization of HbA2 measurements should be prioritized as more techniques become available in routine laboratory practice.

Transition of Care for Patients with Thalassemia

Thalassemia is one of the most common hemoglobinopathies affecting a large number of people in India and other countries of South-East Asia. For patients with most severe form of the disease- Transfusion Dependent Thalassemia (TDT), stem cell transplantation or gene therapy are only curative treatment which are not available to most of the patients because of lack of experts, financial constraints and lack of suitable donors. In such situations, most cases are managed with regular blood transfusion and iron chelation therapy. With this treatment, over the years, survival of the patients has improved and 20-40% cases are entering into adulthood. In the absence of structured transition of care programs, currently most adult TDT patients are being managed by pediatricians. This article highlights the need for transition of care for TDT patients, barriers to transition and how to overcome the barriers and process of transition of care to adult care team. The importance of empowering the patients in self-management of the disease and educating the adult care team to achieve the desired outcome of transition program is highlighted.

Distribution characteristics and clinical phenotype analyses of hemoglobin variants in the Z region of Central Guangxi, Southern China

OBJECTIVE

To investigate the molecular diagnosis of hemoglobin variants in Z region by Capillary electrophoresis in Central Guangxi, Southern China, and analyze their distribution and phenotypic characteristics, to provide a reference for clinical consultation and prenatal diagnosis for couples.

METHODS

A total of 23,709 subjects were collected for blood routine analysis, hemoglobin analysis, and common α- and β-globin gene loci in Chinese population. The hemoglobin electrophoresis components were divided into Zone 1-Zone 15 (Z1-Z15) by Capillary zone electrophoresis (CE). For samples not clearly detected by the conventional technology, Sanger sequencing, and multiplex ligation-dependent probe amplification (MLPA) were used. Single-molecule real-time (SMRT) sequencing technology was used to analyze rare-type genes in a sample with a structural variation.

RESULTS

Ten rare hemoglobin variants distributed in Z region were detected in 23,709 samples, including Hb Cibeles, which was reported for the first time in Asia; Hb J-Broussais, Hb G-Honolulu and J-Wenchang-Wuming, they were first reported in Guangxi; 1 case of Hb Anti-Lepore Liuzhou, which was a newly discovered hemoglobin variant; hemoglobin variants Hb G-Siriraj, Hb Handsworth, Hb Q-Thailand, Hb Ube-2, Hb NewYork were also detected.

CONCLUSION

There are a few studies on rare hemoglobin variants in Z region in Southern China. Ten rare hemoglobin variants were found in this study. The hematological phenotype and component content of hemoglobin variants are related to the occurrence of thalassemia. This study enriched the data of rare hemoglobin variants in Southern China and provided a comprehensive data basis for prenatal diagnosis of hemoglobin variants in this area.

thalassemia patients

Toxoplasma gondii is a worldwide opportunistic protozoan causing life-threatening infection in immunocompromised patients, while frequently asymptomatic in immunocompetent individuals. The current study aimed to detect T. gondii; serologically and molecularly in ß. thalassemia patients and evaluate the association of infection with some hematological parameters in these patients. Blood samples were collected from 100 ß. thalassemia patients. Serological diagnosis of T. gondii using ELISA for IgG and IgM antibodies was performed. Molecular diagnosis by Real-Time (RE) PCR was performed using specifically designed primers amplifying 389 bp fragments of Toxoplasma genome. 45 patients (45%) had anti-Toxoplasma IgG antibodies with no detectable IgM antibodies while both anti-Toxoplasma IgM and IgG antibodies were noticed in 10 patients (10%). IgM only antibodies were discovered in two cases (2%). The total seropositivity rate among patients was 57%. RE PCR analysis revealed Toxoplasma DNA in 20% out of 100 patients. PCR and serological examination showed slight agreement. A statistically significant relation was observed between the results of IgG and IgM ELISA and PCR for the detection of T. gondii infection among patients with ß. thalassemia. None of the studied risk factors (age, gender, contact with cats, consumption of undercooked meat) or hematological parameters (ESR, anemia degree, ferritin level, type of blood transfusion, spleen status) showed statistically significant association with Toxoplasma infection. It can be concluded that patients with thalassemia have a high risk of infection with T. gondii. RE PCR should be used as a diagnostic method in association with serology especially in immunocompromised patients to increase sensitivity.

Left Ventricular Myocardial Dysfunction Evaluation in Thalassemia Patients Using Echocardiographic Radiomic Features and Machine Learning Algorithms

Heart failure caused by iron deposits in the myocardium is the primary cause of mortality in beta-thalassemia major patients. Cardiac magnetic resonance imaging (CMRI) T2* is the primary screening technique used to detect myocardial iron overload, but inherently bears some limitations. In this study, we aimed to differentiate beta-thalassemia major patients with myocardial iron overload from those without myocardial iron overload (detected by T2*CMRI) based on radiomic features extracted from echocardiography images and machine learning (ML) in patients with normal left ventricular ejection fraction (LVEF > 55%) in echocardiography. Out of 91 cases, 44 patients with thalassemia major with normal LVEF (> 55%) and T2* ≤ 20 ms and 47 people with LVEF > 55% and T2* > 20 ms as the control group were included in the study. Radiomic features were extracted for each end-systolic (ES) and end-diastolic (ED) image. Then, three feature selection (FS) methods and six different classifiers were used. The models were evaluated using various metrics, including the area under the ROC curve (AUC), accuracy (ACC), sensitivity (SEN), and specificity (SPE). Maximum relevance-minimum redundancy-eXtreme gradient boosting (MRMR-XGB) (AUC = 0.73, ACC = 0.73, SPE = 0.73, SEN = 0.73), ANOVA-MLP (AUC = 0.69, ACC = 0.69, SPE = 0.56, SEN = 0.83), and recursive feature elimination-K-nearest neighbors (RFE-KNN) (AUC = 0.65, ACC = 0.65, SPE = 0.64, SEN = 0.65) were the best models in ED, ES, and ED&ES datasets. Using radiomic features extracted from echocardiographic images and ML, it is feasible to predict cardiac problems caused by iron overload.

Case report: Identification of a novel triplication of alpha-globin gene by the third-generation sequencing: pedigree analysis and genetic diagnosis

BACKGROUND

Thalassemia, a common autosomal hereditary blood disorder worldwide, mainly contains α- and β-thalassemia. The α-globin gene triplicates allele is harmless for carriers, but aggravates the phenotype of β-thalassemia. Therefore, it is particularly crucial to accurately detect the structural variants of α-globin gene clusters.

CASE REPORT

We reported a 28-year-old man, the proband, with microcytic hypochromic anemia. From pedigree analysis, his mother and sister had hypochromic microcytosis, and his father was normal. Genetic testing of thalassemia identified a novel α-globin gene triplicate named αααanti4.2del726bp (NC_000016.10:g.170769_174300dupinsAAAAAA) by third-generation sequencing (TGS) in the proband and his father, which was further validated by multiplex ligation-dependent probe amplification (MLPA) and Sanger sequencing. The genotypes of the proband's mother and sister were both -α3.7/αα compounded with heterozygous HBB:c.126_129delCTTT. They were categorized as silent α-thalassemia with co-inheritance of β-thalassemia trait. The proband's genotype additionally had the α-globin gene triplicates compared with his mother and sister, which increased the imbalance between α/β-globin, so the proband had more severe hematological parameters. The proband's wife was diagnosed as HBA2:c.427T > C heterozygosis, and his daughter had the novel α-globin gene triplicates compounded with HBA2:c.427T > C, therefore the girl might be asymptomatic.

CONCLUSION

The identification of the novel α-globin gene triplicates provides more insight for the research of thalassemia variants and indicates that TGS has significant advantages on genetic testing of thalassemia for the reliability, accuracy and comprehensiveness.

Molecular characterisation of Hb Akron [β52 (D3) Asp→Val] combined with thalassaemia in a Chinese family

AIMS

Hb Akron (HBB:c.158A>T) is a rare β-chain variant and many characteristics about its clinical features still remain unclear. In this study, we aimed to explore the molecular and haematological characterisations of previously undescribed states for Hb Akron associated with different forms of thalassaemia.

METHODS

Haematology and genetic analysis were performed in 9 members from a Chinese Zhuang ethnic family.

RESULTS

Hb Akron in various combinations with β0-thalassaemia and α0-thalassaemia were identified and characterised. Simple heterozygote for Hb Akron is asymptomatic, while the compound heterozygotes of Hb Akron associated with the β0-thalassaemia mutation generates a more severe haematological phenotype than Hb Akron or β0-thalassaemia mutation seen in isolation. The specific peak of Hb Akron appears at Zone D (195-225 s) in the state of heterozygote and compound heterozygote on haemoglobin capillary electrophoresis device, and the reduction of Hb Akron level in heterozygotes is proportional to the degree of α-globin gene deficiency.

CONCLUSIONS

We have for the first time described the genetic and haematological characteristics of Hb Akron combined with different thalassaemia mutations, which will provide useful information for genetic counselling and prenatal diagnostic service of this mutation in a population with high prevalence of thalassaemia.

CHMMOTv1 - cardiac and hepatic multi-echo (T2*) MRI images and clinical dataset for Iron overload on thalassemia patients

INTRODUCTION

Regarding deep learning networks in medical sciences for improving diagnosis and treatment purposes and the existence of minimal resources for them, we decided to provide a set of magnetic resonance images of the cardiac and hepatic organs.

DATABASE DESCRIPTION

The dataset included 124 patients (67 women and 57 men) with thalassemia (THM), the age range of (5-52) years. Patients were divided into two groups: with follow-up (1-5 times) at time intervals of about (5-6) months and without follow-up. T2* and, R2* values, the results of the Cardiac and Hepatic overload report (normal, mild, moderate, severe), and laboratory tests including Ferritin, Bilirubin (D, and T), AST, ALT, and ALP levels were provided as an Excel file. Also, the details of the patients' Echocardiogram data have been made available. This dataset CHMMOTv1) has been published in Mendeley Dataverse and also is accessible through the web at: http://databiox.com .

Two Novel α-Thalassemia Mutations CD 39 -C [Thr > Pro] and CD 109 ACC > CCC [Thr > Pro] Identified in Two Chinese Families: A Case Report

We reported the identification of two rare α-thalassemia silent carriers with novel HBA1 mutations of CD 39 -C [Thr > Pro] (HBA1: c.114del; p.Thr39Profs*11) and CD 109 ACC > CCC [Thr > Pro] (HBA1: c.325A > C; p. Thr109Pro), respectively. The two probands were pregnant women diagnosed with mild hypochromic anemia or microcytic hypochromic anemia by routine blood tests. They started iron therapy before taking differential diagnosis from iron deficiency anemia. After wait and watch approach, they both accepted thalassemia genetic screening, which identified CD 39 -C [Thr > Pro] and CD 109 ACC > CCC [Thr > Pro], respectively. Due to inappropriate iron therapy, worse anemia and iron overload were noticed in the first proband, but no obvious side effect was found in both probands. Functional analysis showed that, relative to the wild type, CD 39 -C [Thr > Pro] considerably reduced the expression of the HBA1 protein while CD 109 ACC > CCC [Thr > Pro] only had a minor impact. Our study highlighted the importance of gestational thalassemia screening based on next-generation sequencing for identifying novel rare thalassemia variants and increased our understanding about the relationship between genotype and phenotype of α-thalassemia.

Molecular spectrum and prevalence of thalassemia investigated by third-generation sequencing in the Dongguan region of Guangdong Province, Southern China

BACKGROUND

PCR, Sanger sequencing and NGS are often employed for carrier screening of thalassemia but all of these methods have limitations. In this study, we evaluated a new third-generation sequencing-based approach termed comprehensive analysis of thalassemia alleles (CATSA) to explore the prevalence of thalassemia in the Dongguan region of southern China.

METHODS

19,932 subjects were recruited for thalassemia screening and hemoglobin testing was performed for each of them. Routine PCR was performed for all the hemoglobin testing-positive subjects and CATSA was conducted for randomly selected subjects from hemoglobin testing-positive and negative subjects.

RESULTS

In the 2716 subjects tested both by PCR and CATSA, 2569 had the same results and 147 had discordant results between the two methods. Sanger sequencing, specially designed PCR and MLPA confirmed the results of CATSA were all correct. In total, CATSA correctly detected 787 subjects with variants while routine PCR correctly detected 640 subjects with variants. CATSA yielded a 5.42% (147 of 2716) increment compared with routine PCR. In the 447 hemoglobin testing-negative subjects, CATSA identified pathogenic variants in 12 subjects. Moreover, CATSA identified a novel deletion (chr16:171262-202032) in the α-globin gene cluster. As a result, the deduced carrier frequency of α-thalassemia,β-thalassemia and α-/β-thalassemia was 5.62%, 3.85% and 0.93%, respectively.

CONCLUSIONS

Our study demonstrated CATSA was a more comprehensive and precise approach than the routine PCR in a large scale of samples, which is highly beneficial for carrier screening of thalassemia. It provided a broader molecular spectrum of hemoglobinopathies and a better basis for a control program in Dongguan region.

A highly sensitive self-powered sensing method designed on DNA circuit strategy and MoS2 hollow nanorods for detection of thalassemia

Thalassemia is one of the most common monogenic diseases, which seriously affects human growth and development, cardiovascular system, liver, etc. There is currently no effective cure for this disease, making screening for thalassemia particularly important. Herein, a self-powered portable device with high sensitivity and specificity for efficiently screening of low-level thalassemia is developed which is enabled with AuNPs/MoS2@C hollow nanorods and triple nucleic acid amplification technologies. It is noteworthy that AuNPs/MoS2@C electrode shows the advantages of high electrocatalytic activity, fast carrier migration rate and large specific surface area, which can significantly improve the stability and output signal of the platform. Using high-efficiency tetrahedral DNA as the probe, the target CD122 gene associated with thalassemia triggers a catalytic hairpin assembly reaction to achieve CD122 recycling while providing binding sites for subsequent hybridization chain reaction, greatly improving the detection accuracy and sensitivity of the device. A reliable electrochemical/colorimetric dual-mode assay for CD122 is then established, with a linear response range of 0.0001-100 pM for target concentration and open circuit voltage, and the detection limit is 78.7 aM (S/N = 3); a linear range of 0.0001-10000 pM for CD122 level and RGB Blue value, with a detection limit as low as 58.5 aM (S/N = 3). This method achieves ultra-sensitive and accurate detection of CD122, providing a new method for the rapid and accurate screening of thalassemia.

'3D-QSAR-based, pharmacophore modelling, virtual screening, and molecular docking studies for identification of hypoxia-inducible factor-1 inhibitor with potential bioactivity

Iron overload is a primary cause of vital organ failure in patients with blood transfusion-dependent beta-thalassemia, and the hypoxia-inducible factor-1 α (HIF-1α) plays an important role in iron homeostasis pathway. HIF-1α modulation as a potential therapeutic target approach for iron chelation in hepatocyte cells. In this study, we used a 3D quantitative structure-activity relationship (QSAR) analysis to predict the inhibitory activity of HIF-1α inhibitors for iron chelation in liver cells. These feature descriptors were used to build a 3D-QSAR model, which was validated using Cost analysis and Fischer's randomization test. The model was used to virtually search the chemical compound libraries for potential inhibitor candidates with least inhibitory activity. The High-throughput Docking (Libdock) approach was used to dock large repositories of chemical molecules. Following Libdock score screening, the protein-ligand poses were docked using docking optimization (Cdocker) method. Binding energy were calculated for the protein-ligand poses of lowest -Cdocker Energy and -Cdocker Interaction. Further, side chain hopping method was used to generate lead novel ligand from best hit pose of ligand. Molecular dynamics simulation study to evaluate the lead novel ligand. Our study demonstrates the utility of 3D-QSAR pharmacophore screening in predicting the inhibitory activity for target. Inhibition strategy for iron chelation provides an alternative routes for reducing the iron content.

Defects in Bone and Bone Marrow in Inherited Anemias: the Chicken or the Egg

PURPOSE OF REVIEW

Recently, there has been an increasing number of studies on the crosstalk between the bone and the bone marrow and how it pertains to anemia. Here, we discuss four heritable clinical syndromes contrasting those in which anemia affects bone growth and development, with those in which abnormal bone development results in anemia, highlighting the multifaceted interactions between skeletal development and hematopoiesis.

RECENT FINDINGS

Anemia results from both inherited and acquired disorders caused by either impaired production or premature destruction of red blood cells or blood loss. The downstream effects on bone development and growth in patients with anemia often constitute an important part of their clinical condition. We will discuss the interdependence of abnormal bone development and growth and hematopoietic abnormalities, with a focus on the erythroid lineage. To illustrate those points, we selected four heritable anemias that arise from either defective hematopoiesis impacting the skeletal system (the hemoglobinopathies β-thalassemia and sickle cell disease) versus defective osteogenesis resulting in impaired hematopoiesis (osteopetrosis). Finally, we will discuss recent findings in Diamond Blackfan anemia, an intrinsic disorder of both the erythron and the bone. By focusing on four representative hereditary hematopoietic disorders, this complex relationship between bone and blood should lead to new areas of research in the field.

Pancreatic fatty replacement as risk marker for altered glucose metabolism and cardiac iron and complications in thalassemia major

OBJECTIVES

This multicenter study assessed the extent of pancreatic fatty replacement and its correlation with demographics, iron overload, glucose metabolism, and cardiac complications in a cohort of well-treated patients with thalassemia major (TM).

METHODS

We considered 308 TM patients (median age: 39.79 years; 182 females) consecutively enrolled in the Extension-Myocardial Iron Overload in Thalassemia Network. Magnetic resonance imaging was used to quantify iron overload (IO) and pancreatic fat fraction (FF) by T2* technique, cardiac function by cine images, and to detect replacement myocardial fibrosis by late gadolinium enhancement technique. The glucose metabolism was assessed by the oral glucose tolerance test.

RESULTS

Pancreatic FF was associated with age, body mass index, and history of hepatitis C virus infection. Patients with normal glucose metabolism showed a significantly lower pancreatic FF than patients with impaired fasting glucose (p = 0.030), impaired glucose tolerance (p < 0.0001), and diabetes (p < 0.0001). A normal pancreatic FF (< 6.6%) showed a negative predictive value of 100% for abnormal glucose metabolism. A pancreatic FF > 15.33% predicted the presence of abnormal glucose metabolism. Pancreas FF was inversely correlated with global pancreas and heart T2* values. A normal pancreatic FF showed a negative predictive value of 100% for cardiac iron. Pancreatic FF was significantly higher in patients with myocardial fibrosis (p = 0.002). All patients with cardiac complications had fatty replacement, and they showed a significantly higher pancreatic FF than complications-free patients (p = 0.002).

CONCLUSION

Pancreatic FF is a risk marker not only for alterations of glucose metabolism, but also for cardiac iron and complications, further supporting the close link between pancreatic and cardiac disease.

KEY POINTS

• In thalassemia major, pancreatic fatty replacement by MRI is a frequent clinical entity, predicted by a pancreas T2* < 20.81 ms and associated with a higher risk of alterations in glucose metabolism. • In thalassemia major, pancreatic fatty replacement is a strong risk marker for cardiac iron, replacement fibrosis, and complications, highlighting a deep connection between pancreatic and cardiac impairment.

Contraceptive use and sexual quality of life of patients with thalassemia in Northern Cyprus: a descriptive cross-sectional study

Objective

Although contraception methods are an important factor affecting sexual life, no literature has been recorded about the contraceptive methods used and the sexual life of thalassemia patients. The aim of this study is to document the effects of and preferences of contraception methods used in the sexual lives of patients with thalassemia.

Methods

The descriptive and cross-sectional study took place in Northern Cyprus at a Thalassemia Center in a State Hospital. The study sample consisted of 100 thalassemia major or intermedia patients. The data includes descriptive characteristics, the preference of contraception methods used by men and women and Sexual Quality of Life Questionnaires.

Results

Participants learned about contraception methods mostly from social media/internet, and 58.3% of the women and 46.2% of the men did not use any contraception method within the last year. Women's sexual quality of life score was 70.3±19.9 and men's Sexual Quality of Life score was 78.9±20.6. Women having knowledge of contraception methods had higher scores than man (p<0.05). Male patients not having physical exercise had sexual quality of life scores significantly lower than those who followed exercise programs (p<0.05).

Conclusions

Results indicate a significant need to include family planning and sexual health subjects that specifically address thalassemia patients.

Challenges of having a child with thalassemia in Pakistan: A phenomenological study

BACKGROUND

Thalassemia is a persistent hemolytic disease and has debilitating effects on patients and their parents. Parents of these children experience pain and suffer from additional emotional strain as they provide daily and lifetime care and are mostly concerned about the health and future of their children.

AIM

The study aimed to understand the experiences of parents of children with thalassemia related to their family, financial, social, treatment, and psychological issues in Pakistan.

METHODS

This descriptive phenomenological study recruited 21 parents of children with thalassemia through purposive sampling until data saturation was achieved. Analysis of transcribed interviews was performed through Colaizzi's method and themes and subthemes revolving around diagnosis, challenges, and treatment issues were extracted.

FINDINGS

A total of 21 Pakistani parents participated in this study. Most of the participants were females (n = 16, 76.19%), housewives/stay-at-home moms (n = 13 (61.90%), and were uneducated (n = 6, 28.57%). Regarding genetic traits, only three (14.28%) parents declared that they had genetic traits of thalassemia. The findings of our study revealed that thalassemia is enormously influenced by psychosocial and economic problems because of this disease in their families.

CONCLUSION

Our findings indicated that parents of these children face multi-faceted challenges, such as physical, socio-emotional, financial, and familial. These findings may lead to an adequate understanding of their individual needs and efficient utilization of supportive and care programs.

PRACTICE IMPLICATIONS

An understanding of such experiences, involving those distinctive to Pakistani culture, is especially vital to inform the care of these children and enhance their quality of life.

One-step genotyping of α-thalassaemia by multiplex symmetric PCR melting curve

AIMS

Alpha-thalassaemia is one of the most common monogenic disorders worldwide. Due to high guanine-cytosine (GC) content and high mutation diversity in α-globin gene cluster, deletional and non-deletional mutations were usually separately detected with different methods. The aim of this study was to develop a novel one-step method for α-thalassaemia genotyping.

METHODS

A multiplex symmetric PCR melting curve strategy was designed for one-step α-thalassaemia genotyping. Based on this strategy, a novel method was developed to simultaneously detect four common deletional (-α3.7 , -α4.2 , _ _SEA , --THAI ) and five common non-deletional (αCD30(-GAG)α, αCD31(G>A)α, αWSα, αQSα, αCSα) α-thalassaemia mutations in a closed-tube reaction. This method was also evaluated by double-blind detection of 235 genotype-known samples and 1630 clinical samples.

RESULTS

All nine α-thalassaemia mutations could be accurately identified by this novel method within 3 hours. The evaluation results also showed a 100% concordance with comparison methods.

CONCLUSIONS

This method is rapid, accurate, low-cost and easy to operate, which can be used for molecular screening and genetic diagnosis of α-thalassaemia in clinical practice. The multiplex symmetric PCR melting curve strategy designed in this study can also provide an effective approach to the method development for high GC content templates and multiple mutations.

Acute spinal cord compression in the setting of chronic extramedullary hematopoiesis of the thoracic spine

Background

Though rare, pathologic extramedullary hematopoiesis (EMH) can occur in response to myeloproliferative disorders and may present as paravertebral masses.

Case Description

We describe a 63-year-old female with unspecified thalassemia, hemochromatosis, and known asymptomatic extramedullary hematopoiesis of the thoracic spine who acutely developed severe spinal cord compression and a T9 vacuum phenomenon fracture 7 months after her initial diagnosis.

Outcome

The patient was treated with urgent decompression and T9 kyphoplasty, which resulted in complete resolution of her neurological deficits.

Conclusions

The timeline of symptomatology in the case suggests that asymptomatic patients with T-spine extramedullary hematopoiesis can develop progressive neurologic deterioration and atraumatic compression fractures culminating in acute spinal cord injury. While it may be appropriate to treat asymptomatic patients conservatively, surgical decompression must always remain a consideration.

Molecular analysis and clinical significance of hemoglobin Quong Sze in Huizhou city, Southern China

OBJECTIVE

Hemoglobin Quong Sze (Hb QS) is one of the most common non-deletional α-thalassemia (α-thal), which is prevalent in the Southern Chinese population. However, there are still few comprehensive researches on the molecular characterization of Hb QS. So it is important to find out appropriate diagnosis and characterization of Hb QS carrier for genetic counseling.

MATERIALS AND METHODS

A hematological screening including hematological indices and hemoglobin analysis was performed in 113,400 individuals from Huizhou city, Southern China. Then, suspected thalassemia carriers were detected by a suspension-array system and DNA sequencing for α- and β-thal.

RESULTS

In our study, we identified 521 subjects who were Hb QS carriers, including fourteen different genotypes. Among them, 445 Hb QS heterozygotes showed a decrease in the mean corpuscular hemoglobin (MCH), 16 compound heterozygotes for Hb QS/α+-thal presented mild thalassemia, 28 Hb QS in combination with --SEA/αα manifested as Hb H disease, varying clinical symptoms from only moderate anemia to severe anemia and requiring blood transfusion, and 29 double heterozygotes for Hb QS and β-thal behaved as β-thal trait. The mean corpuscular volume (MCV) and MCH were significantly reduced and no Hb H peak could be detected in one patient with Hb H-Hb QS and β-thal. Meanwhile, we identified two homozygous Hb QS carriers, who showed mild to moderate anemia and increased Hb A2 level but negative results from a sequencing analysis for the first time. Additionally, Comparison of hematological parameters among the major four genotype groups showed significant differences in most box-whisker plots.

CONCLUSION

People who originated from Huizhou city showed many genotypes and diversity in the clinical manifestations of Hb QS carriers. This study enlarges the mutation spectrum of α-thal and emphasizes that reliable detection of the gene mutations is important for genetic counseling. It also strengthens the prevention and control of thalassemia.

Measurement of Erythrocyte Lifespan Using a CO Breath Test in Patients with Thalassemia and the Impact of Treatment

Background: Thalassemia comprises a diverse group of genetic disorders that affects the synthesis of globin chains, with a global distribution. The use of erythrocyte lifespan (ELS) to assess differences among patients with different types of thalassemia and the efficacy of splenectomy has not been implemented.  

Extramedullary haematopoiesis in patients with thalassemia: a cross-sectional description of its prevalence, clinical features and survival

INTRODUCTION

Despite knowledge advances on extramedullary haematopoiesis (EMH) in thalassemic patients, the real picture remains an open issue.

OBJECTIVES

To assess EMH prevalence in patients with thalassemia major (TM) and intermedia (TI), to describe magnetic resonance imaging (MRI) findings and to explore clinical risk factors.

METHODS

In this cross-sectional study, images and clinical records of 184 consecutive patients with thalassemia who underwent T2* MRI between 2004 and 2011 were reviewed. Association of EMH with survival was investigated for patients with available follow-up charts.

RESULTS

EMH was detected in 16/168 (9.5%) patients with TM (aged 19-49 years) and in 3/16 (18.8%) with TI (aged 36-41 years). Most (88%) had paravertebral thoracic and/or abdominal masses. Age was significantly associated with EMH risk (hazard ratio, [HR] 1.10/year; confidence interval [CI]: 1.03-1.18; p-value < 0.001), while lower pancreatic iron content by T2*MRI (HR: 0.94/ms; CI: 0.89-0.99; p-value = 0.049) was a protective factor. Estimated survival rate was superior for EMH-positive (n = 19) when compared to EMH-negative patients (n = 75) (p-value = 0.013).

CONCLUSIONS

The prevalence of EMH was 10.3% (19/184), presented mainly as tumoral masses of 3 to 10 cm. Age was a risk factor for EMH development, while lower pancreatic iron might be a protective factor in this cohort.

Next-generation sequencing analysis of the molecular spectrum of thalassemia in Southern Jiangxi, China

BACKGROUND

Thalassemia is an extremely prevalent monogenic inherited blood disorder in southern China. It is important to comprehensively understand the molecular spectrum of thalassemia in an area with such a high prevalence of thalassemia before taking appropriate actions for the prevention and treatment of this disorder. Herein, we explored the clinical feasibility of using next-generation sequencing (NGS) for large-scale population screening to illustrate the prevalence and spectrum of thalassemia in Southern Jiangxi.

METHODS

Blood samples collected from 136,312 residents of reproductive age in Southern Jiangxi were characterized for thalassemia by NGS. A retrospective analysis was then conducted on blood samples determined to be positive for thalassemia.

RESULTS

In total, 19,827 (14.545%) subjects were diagnosed as thalassemia carriers, and the thalassemia prevalence rate significantly varied by geographical region (p < 0.001). A total of 40 α-thalassemia genotypes including 21 rare genotypes were identified, with -@-SEA/αα being the most prevalent genotype. 42 β-thalassemia genotypes including 27 rare genotypes were identified, with the most common mutation IVS II-654 C > T accounting for 35.257% of these β-thalassemia genotypes. Furthermore, 74 genotypes were identified among 608 individuals with combined α- and β-thalassemia. Notably, most individuals with rare thalassemia mutations had mildly abnormal hematologic parameters including microcytic hypochromia.

CONCLUSIONS

Our findings demonstrate the great heterogeneity and diverse spectrum of thalassemia in Southern Jiangxi, emphasizing the importance and necessity of persistent prevention and control of thalassemia in this region. Additionally, our findings further suggest that NGS can effectively identify rare mutations and reduce the misdiagnosis rate of thalassemia.

Adolescents' experiences and views of the national school-based thalassaemia screening programme in Malaysia: a qualitative study

In 2016, a national school-based thalassemia screening programme was implemented in Malaysia. This study aimed to explore the experiences and views of adolescents from an urban school who had undergone the screening programme. We carried out in-depth interviews with 18 participants aged between 18 and 19 years old, with 12 of them identified as carriers during the school screening. Interviews were transcribed verbatim and analysed using thematic analysis. Three main themes emerged from this study: (1) issues encountered at various levels of the school screening programme: appropriate age for screening, thalassaemia education in school, parental consent and follow-up visit and post-test counselling; (2) experiencing emotional rollercoaster: worry, anxiety, shame, stigma; (3) choosing future partners after carrier status was known-prepared or unprepared? Various issues and screening-related challenges were encountered before, during and after the screening test. Recommendations include improving thalassaemia screening education for both school-going adolescents and parents, and better follow-up care and support for those identified as carriers. These will help stakeholders to be well informed and supportive of thalassaemia screening in schools.

Differences in the distribution of hemoglobin variants according to the geographic regions in a Colombian population

INTRODUCTION

Colombia has been subject to intense genetic and cultural currents due to its geographical location. Hemoglobinopathies are the most common recessive diseases found worldwide and represent an important public health problem, according to the region and ancestry of each country.

OBJECTIVES

To evaluate the frequency of hemoglobin variants according to the geographical region in a population group adjusted to sex and age in Colombia.

METHODS

This was a descriptive retrospective study of hemoglobin variants performed by electrophoresis in patients treated at and/or referred to specialized care institutions in Bogota, Colombia between January 2009 and December 2020.

RESULTS

A total of 2,224 results were analyzed, 48.4% male and 51.5% female; 63.3% of patients were without alterations, 14.3% presented with thalassemia, 17.3%, HbS, 2.3%, HbS/C, 1.8%, HbC, 0.5%, HbE and 0.5% persistent HbF, with HbS being more prevalent in males (p = 0.005). When assessing the geographical regions of Colombia, a higher prevalence of HbS was found in the Pacific (p = 0.005) and Caribbean regions, while Thalassemia and HbS were more prevalent in the Andean and Orinoquia regions, and it was rare to find any hemoglobinopathies (p = 0.0001) in the Amazonian region.

CONCLUSIONS

The main hemoglobinopathies found in Colombia are HbS, predominantly in males, and Thalassemia. The distribution of hemoglobinopathies in different geographical regions of Colombia is influenced by ancestry.

Thalassemia carrier status and groundwater iron: Implication for iron supplementation program for children in Bangladesh

Background

Thalassemia, a congenital disorder of hemoglobin synthesis is characterized by low hemoglobin and high iron status, is prevalent in Bangladesh. Iron, consumed through drinking groundwater also increases the population iron status in Bangladesh. The study examined the effect of iron containing micronutrient powder (MNP) on the hemoglobin and ferritin status in Bangladeshi children with thalassemia and their non-thalassemia peers exposed to a high concentration of iron from drinking groundwater.

Design and methods

Three hundred twenty-seven children aged 2-5 years were recruited for an MNP efficacy trial. A sub sample (n = 222) were screened for thalassemia. Hemoglobin and ferritin levels were measured in children with and without thalassemia. Intake of iron from the key sources-diet, groundwater and MNP was measured. Mann Whitney and t-test were employed to compare the groups.

Results

Hemoglobin concentration of the children with thalassemia at the endpoint remained unchanged relative to the baseline; 11.56 ± 0.59 g/dL (Endpoint) versus 11.6 ± 0.54 g/dL (Baseline), p = 0.83. In children without thalassemia hemoglobin tended to increase; 12.54 ± 0.72 g/dL (Endpoint) versus 12.41 ± 0.72 g/dL (baseline), p = 0.06. Baseline reserve of body iron was significantly (p = 0.03) higher in thalassemia carriers (594 gm) compared to their non-carrier peers (558 gm). The increase of the infection-adjusted ferritin from baseline to the endpoint was 7.37% (p = 0.7) and 10.17% (p = 0.009) in the carrier and non-carrier groups respectively.

Conclusions

In Bangladesh, the coexistence of thalassemia and the exposure to a high concentration of iron from drinking groundwater renders anemia prevention program with a low iron MNP potentially lesser hazardous to the thalassemia carriers.