Thalassemia and hemoglobin e in southern thai blood donors

Survival of transfused red blood cells from a donor with alpha-thalassemia trait in a recipient with sickle cell disease

BACKGROUND

Post-transfusion survival of donor red blood cells (RBCs) is important for effective chronic transfusion therapy in conditions including sickle cell disease (SCD). Biotin labeling RBCs allows direct in vivo measurement of multiple donor RBC units simultaneously post-transfusion.

STUDY DESIGN AND METHODS

In an observational trial of patients with SCD receiving monthly chronic transfusion therapy, aliquots of RBCs from one transfusion episode were biotin-labeled and infused along with the unlabeled RBC units. Serial blood samples were obtained to measure RBC survival. Donor units were tested for RBC indices, hemoglobin fractionation, and glucose-6-phosphate dehydrogenase (G6PD) enzyme activity. For microcytic donor RBCs (MCV < 70 fL), HBA1 and HBA2 genetic testing was performed on whole blood.

RESULTS

We present one recipient, a pediatric patient with SCD and splenectomy who received two RBC units with aliquots from each unit labeled at distinct biotin densities (2 and 18 μg/mL biotin). One donor unit was identified to have microcytosis (MCV 68.5 fL after biotinylation); whole blood sample obtained at a subsequent donation showed 2-gene deletion alpha-thalassemia trait (ɑ-3.7kb/ɑ-3.7kb) and normal serum ferritin. G6PD activity was >60% of normal mean for both. The RBCs with alpha-thalassemia RBC had accelerated clearance and increased surface phosphatidylserine post-transfusion, as compared with the normocytic RBC (half life 65 vs. 86 days, respectively).

DISCUSSION

Post-transfusion RBC survival may be lower for units from donors with alpha-thalassemia trait, although the impact of thalassemia trait donors on transfusion efficacy requires further study.

Association of thalassemia, hemoglobinopathies, and vitamin D levels with lipid profile in adults: Community-based research in southern Thai population

This study explored the frequency of lipid-lowering drug use in the thalassemia population and investigated the association of thalassemia, hemoglobinopathies, and serum 25(OH)D levels with lipid profile and red blood cell parameters. A combination of cross-sectional and community-based studies was conducted with 615 participants from the southern Thai population. Thalassemia and hemoglobinopathies were diagnosed using hemoglobin analysis and polymerase chain reaction-based methods to genotype globin genes. Biochemical parameters such as lipid profile, fasting blood sugar (FBS), and serum 25(OH)D levels were assessed using standard enzymatic methods and electrochemiluminescence immunoassays. Differences in the means of hematological and biochemical parameters between the thalassemia and non-thalassemia groups were compared and analyzed. A significantly lower frequency of lipid-lowering drug use was observed in the thalassemia group. Thalassemia, with clearly defined abnormalities in red blood cells, is associated with a 4.72-fold decreased risk of taking lipid-lowering drugs. Among thalassemia participants, the total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) levels were significantly lower than those in non-thalassemia participants. The prevalence of hypovitaminosis D in carriers of thalassemia and/or hemoglobinopathies in the southern Thai population was 53 % in females and 21 % in males. The highest lipid profile was observed in samples without thalassemia and hypovitaminosis D. The genetics of thalassemia and hemoglobinopathies with obviously abnormal red blood cells could explain the variable lipid levels, in addition to lipid metabolism-related genes and environmental factors. However, the effect of thalassemia on lipid levels in each population may differ according to its prevalence. A larger sample size is required to confirm this association, especially in countries with a high prevalence of thalassemia.

Hematological Profile of Hb Adana Among High School Students in Northeast Peninsular Malaysia

Background Hb Adana is a non-deletional alpha (α)-thalassaemia variant resulting from mutations in α1- or α2-globin codon 59 (αCD59), leading to the production of unstable α-globin. Clinical manifestations can vary from silent carrier status to dependence on blood transfusions, hepatosplenomegaly, skeletal deformities, and spinal cord compression. Despite the significance of Hb Adana inheritance, studying this variant poses challenges due to the scarcity of molecular tests and the potential for routine diagnoses to be overlooked. This study aims to investigate the prevalence of Hb Adana among local high school students and assess the hematological parameters and hemoglobin analysis of Hb Adana in Malaysia. Methodology This retrospective study analyzed 13,721 blood samples collected from high school students participating in Malaysia's National Thalassaemia Screening Program at Hospital Raja Perempuan Zainab II (HRPZ II). Deletional α-thalassaemia was detected using multiplex gap-polymerase chain reaction (PCR), while common non-deletional α-thalassaemia was identified using multiplex amplification refractory mutation system (ARMS) PCR. Data were extracted from the HRPZ II database for analysis. Results Among the participants, 2327 individuals were found to have either common deletional (n=1037, 44.6%) or non-deletional (n=1290, 55.4%) α-thalassaemia. Hb Constant Spring was the most prevalent non-deletional α-thalassaemia, accounting for 53.03% of cases. Thirty-one participants (1.33%) exhibited αCD59α/αα, and one (0.04%) had αCD59α/-α3.7. Among the 32 subjects with Hb Adana, 87.5% were Malay, and 12.5% were Orang Asli. Additionally, seven cases of HbE/Hb Adana co-inheritance were identified. Hemoglobin levels in heterozygous Hb Adana individuals ranged from mild anemia to normal, between 95 g/L and 153 g/L. Mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) were approximately 73 fL and 23 pg, respectively. Conclusion This study delineates the distribution of α-thalassaemia mutation patterns among high school students in Kelantan, Northeast Peninsular Malaysia. Our findings indicate that Hb Adana is rare in our region and co-inheritance with an α-gene deletion results in α+-thalassaemia and with HbE, α0-thalassaemia. All heterozygous Hb Adana individuals exhibited low MCVs and MCHs.

Current Status of β-Thalassemic Burden in India

Thalassemia is a major public health concern in India. The thalassemic burden in India is high, with an estimated 100,000 patients diagnosed with β-thalassemia syndrome. However, the exact number is unknown because of the absence of National Registries for patients. India alone contributes to approximately 25% of the global β-thalassemia burden. A possible option to control this burden is to endorse education and awareness programs, compulsory prenatal screening, and develop suitable facilities for genetic counseling, and availability of cost-effective diagnostic tests in India, especially in rural areas. In addition to the various clinical complications associated with thalassemia, lifelong intervention creates mental and physical trauma in patients and their relatives. Government and nongovernment organizations have initiated screening programs to prevent thalassemia. However, prenatal screening is not mandatory, and the reachability of screening programs in rural areas is yet to begin. This review article will discuss the progress in thalassemia research in India, including its prevalence, spectrum of β-thalassemia mutations, preventive and therapeutic measures, and awareness programs. More importantly, we will discuss the need and roadmap to strengthen prevention programs in India.

Blood Donors with Thalassemic Trait, Glucose-6-Phosphate Dehydrogenase Deficiency Trait, and Sickle Cell Trait and Their Blood Products: Current Status and Future Perspective

The use of blood products for different medical purposes has increased in recent years. To meet increasing demand, some blood centers allow volunteer donors with thalassemic trait, glucose-6-phosphate dehydrogenase deficiency (G6PD) trait, and sickle cell trait (SCT) to donate blood if their hemoglobin values fall within acceptable ranges and show no signs of hemolysis. Currently, there are no standard guidelines or policies regarding the use or management of blood products obtained from these donors. However, in recent years, there has been advanced research on eligible donors who have these underlying conditions. In this review, we summarize the current knowledge from in vitro and in vivo studies regarding donor characteristics, changes in physical and biochemical parameters in blood products during processing and storage, and posttransfusion efficacy of blood products. In addition, we discuss some unresolved issues concerning blood products from thalassemic trait, G6PD-deficiency trait, and SCT donors.

Single Nucleotide Polymorphisms in XMN1-HBG2, HBS1L-MYB, and BCL11A and Their Relation to High Fetal Hemoglobin Levels That Alleviate Anemia

Anemia is a condition in which red blood cells and/or hemoglobin (Hb) concentrations are decreased below the normal range, resulting in a lack of oxygen being transported to tissues and organs. Those afflicted with this condition may feel lethargic and weak, which reduces their quality of life. The condition may be manifested in inherited blood disorders, such as thalassemia and sickle cell disease, whereas acquired disorders include aplastic anemia, chronic disease, drug toxicity, pregnancy, and nutritional deficiency. The augmentation of fetal hemoglobin (HbF) results in the reduction in clinical symptoms in beta-hemoglobinopathies. Several transcription factors as well as medications such as hydroxyurea may help red blood cells produce more HbF. HbF expression increases with the downregulation of three main quantitative trait loci, namely, the XMN1-HBG2, HBS1L-MYB, and BCL11A genes. These genes contain single nucleotide polymorphisms (SNPs) that modulate the expression of HbF differently in various populations. Allele discrimination is important in SNP genotyping and is widely applied in many assays. In conclusion, the expression of HbF with a genetic modifier is crucial in determining the severity of anemic diseases, and genetic modification of HbF expression may offer clinical benefits in diagnosis and disease management.

Prevalence of G6PD deficiency in Thai blood donors, the characteristics of G6PD deficient blood, and the efficacy of fluorescent spot test to screen for G6PD deficiency in a hospital blood bank setting

BACKGROUND

Transfusion of blood from glucose-6-phosphate dehydrogenase (G6PD) enzyme deficient donors could cause a potentially unfavorable outcome, especially in newborns and those with hemoglobinopathies.

AIMS

To determine the prevalence of G6PD deficiency in Thai blood donors, the characteristics of G6PD deficient blood, and the efficacy of fluorescent spot test (FST) to screen for G6PD deficiency in a hospital blood bank setting.

METHODS

Blood samples were obtained from 514 Thai blood donors who donated blood at Siriraj Hospital (Bangkok, Thailand) during December 2020-February 2021. G6PD deficiency status was screened using FST, and in vitro hemolysis of red blood cell parameters of G6PD deficient blood units was compared with those of normal control units at different time points during 35 days of refrigerated storage.

RESULTS

The prevalence of G6PD deficiency was 7.59% (35 [8.73%] males, 4 [3.54%] females). The sensitivity of FST was 100% (95% confidence interval [CI]: 90.97-100%), and the specificity was 99.58% (95%CI: 98.49-99.95%). In vitro hemolysis was not significantly different between G6PD deficiency and normal controls.

CONCLUSION

The prevalence of G6PD deficiency in this study was 7.59%. FST was demonstrated to be an effective and reliable method for G6PD deficiency screening among Thai blood donors in a hospital blood bank setting.

Storage Duration and Red Blood Cell-Derived Microparticles in Packed Red Blood Cells Obtained from Donors with Thalassemia

OBJECTIVE

To address the effects of storage duration on red blood cell (RBC)-derived microparticles (RMPs) in packed RBCs from donors who have thalassemia.

MATERIALS AND METHODS

Packed RBCs were prepared according to laboratory routine. The quantity of RMPs was determined using FACSCalibur and counting beads.

RESULTS

Across durations of storage, the packed RBCs from donors with thalassemia (n = 28) and healthy volunteers (n = 104) showed average RMPs to be 47,426 (10,139‒127,785) particles/μL vs 49,021 (13,033‒126,749) particles/μL, respectively (P = .63). The peak RMP levels in donors with thalassemia and healthy volunteers, respectively, were shown in products from storage days 34 and 38. Both groups showed a trend toward a positive association between RMP concentration and the duration of storage in packed RBC bags stored under blood bank conditions.

CONCLUSION

Our results suggest that storage-induced RMP release has similar effects in stored packed RBCs obtained from both donors with thalassemia and healthy volunteers.

The Post-Storage Performance of RBCs from Beta-Thalassemia Trait Donors Is Related to Their Storability Profile

Blood donors with beta-thalassemia traits (βThal+) have proven to be good "storers", since their stored RBCs are resistant to lysis and resilient against oxidative/proteotoxic stress. To examine the performance of these RBCs post-storage, stored βThal+ and control RBCs were reconstituted in plasma donated from transfusion-dependent beta-thalassemic patients and healthy controls, and incubated for 24 h at body temperature. Several physiological parameters, including hemolysis, were evaluated. Moreover, labeled fresh/stored RBCs from the two groups were transfused in mice to assess 24 h recovery. All hemolysis metrics were better in the group of heterozygotes and distinguished them against controls in the plasma environment. The reconstituted βThal+ samples also presented higher proteasome activity and fewer procoagulant extracellular vesicles. Transfusion to mice demonstrated that βThal+ RBCs present a marginal trend for higher recovery, regardless of the recipient's immune background and the RBC storage age. According to correlation analysis, several of these advantageous post-storage characteristics are related to storage phenotypes, like the cytoskeleton composition, low cellular fragility, and enhanced membrane proteostasis that characterize stored βThal+ RBCs. Overall, it seems that the intrinsic physiology of βThal+ RBCs benefits them in conditions mimicking a recipient environment, and in the circulation of animal models; findings that warrant validation in clinical trials.

Prevalence and Associated Factors of Anemia among Muslim Students, Nakhon Si Thammarat, Thailand: A Cross-Sectional Study

Anemia is a global public health problem. The prevalence of anemia among different ages, genders or ethnic groups must be clarified in order to solve problems. This study proposed to determine the prevalence and factors related to anemia among the Muslim school-age population in Nakhon Si Thammarat, Thailand. Socio-demographic and anthropometric data were collected by a structured questionnaire. Blood samples were collected from 200 school-age subjects. The thalassemia screening was performed with KKU-OF and KKU-DCIP reagents. The prevalence of anemia in this study was 36.5%, divided into males and females, 33.3% and 39.1%, respectively. The means of Hb, Hct, MCV, MCH, and MCHC in the anemic group were significantly lower. The positive results for KKU-OF or KKU-DCIP or both were 15.0%, 2.5%, and 1.0%, respectively. The result of positive OF test was a significantly independent factor for anemia. The number of family members was 5 to 7 and more than 7 persons are related factors for anemia in this study. In summary, the contribution of thalassemia and socio-economic factor are associated factors to anemia in this population. These findings should be addressed in public health strategies for the control of anemia of school-aged Muslims in the region.

A Southeast Asian Perspective on the COVID-19 Pandemic: Hemoglobin E (HbE)-Trait Confers Resistance Against COVID-19

As of November 25, 2020, over 60 million people have been infected worldwide by COVID-19, causing almost 1.43 million deaths. Puzzling low incidence numbers and milder, non-fatal disease have been observed in Thailand and its Southeast (SE) Asian neighbors. Elusive genetic mechanisms might be operative, as a multitude of genetic factors are widely shared between the SE Asian populations, such as the more than 60 different thalassemia syndromes (principally dominated by the HbE trait). In this study, we have plotted COVID-19 infection and death rates in SE Asian (SEA) countries against heterozygote HbE and thalassemia carrier prevalence. COVID-19 infection and death incidence numbers appear inversely correlated with the prevalence of HbE and thalassemia heterozygote populations. We posit that the evolutionary protective effect of the HbE and other thalassemic variants against malaria and the dengue virus may extend its advantage to resistance to COVID-19 infection, as HbE heterozygote population prevalence appears to be positively correlated with immunity to COVID-19. Host immune system modulations induce antiviral interferon responses and alter structural protein integrity, thereby inhibiting cellular access and viral replication. These changes are possibly engendered by HbE carrier miRNAs. Proving this hypothesis is important, as it may shed light on the mechanism of viral resistance and lead to novel antiviral treatments. This development can thus guide decision-making and action to prevent COVID-19 infection.

Cell-Derived Microparticles in Blood Products from Thalassemic Blood Donors

OBJECTIVE

To determine the number of cell-derived microparticles (MPs) in blood products obtained from donors who have thalassemia.

METHODS

Packed red blood cells (PRBCs), plasma, and platelet concentrate (PC) were prepared according to routine procedures. We used flow cytometry to quantitate the concentration of MPs.

RESULTS

The results of a comparison of MP levels in unprocessed whole blood showed that the concentration of all MPs in the donors without thalassemia trait (n = 255) was higher than in donors with thalassemia trait (n = 70). After processing, increased concentrations of MPs were documented in both groups. Among the blood components, PRBC showed higher platelet-derived MP concentrations in donors with thalassemia than in donors without thalassemia. However, PC showed higher concentrations of total MPs in donors without thalassemia than in donors with that condition.

CONCLUSIONS

Our results suggest little influence of thalassemia-trait status on changes in MP concentrations in blood components.

Paper-based microchip electrophoresis for point-of-care hemoglobin testing

Nearly 7% of the world's population live with a hemoglobin variant. Hemoglobins S, C, and E are the most common and significant hemoglobin variants worldwide. Sickle cell disease, caused by hemoglobin S, is highly prevalent in sub-Saharan Africa and in tribal populations of Central India. Hemoglobin C is common in West Africa, and hemoglobin E is common in Southeast Asia. Screening for significant hemoglobin disorders is not currently feasible in many low-income countries with the high disease burden. Lack of early diagnosis leads to preventable high morbidity and mortality in children born with hemoglobin variants in low-resource settings. Here, we describe HemeChip, the first miniaturized, paper-based, microchip electrophoresis platform for identifying the most common hemoglobin variants easily and affordably at the point-of-care in low-resource settings. HemeChip test works with a drop of blood. HemeChip system guides the user step-by-step through the test procedure with animated on-screen instructions. Hemoglobin identification and quantification is automatically performed, and hemoglobin types and percentages are displayed in an easily understandable, objective way. We show the feasibility and high accuracy of HemeChip via testing 768 subjects by clinical sites in the United States, Central India, sub-Saharan Africa, and Southeast Asia. Validation studies include hemoglobin E testing in Bangkok, Thailand, and hemoglobin S testing in Chhattisgarh, India, and in Kano, Nigeria, where the sickle cell disease burden is the highest in the world. Tests were performed by local users, including healthcare workers and clinical laboratory personnel. Study design, methods, and results are presented according to the Standards for Reporting Diagnostic Accuracy (STARD). HemeChip correctly identified all subjects with hemoglobin S, C, and E variants with 100% sensitivity, and displayed an overall diagnostic accuracy of 98.4% in comparison to reference standard methods. HemeChip is a versatile, mass-producible microchip electrophoresis platform that addresses a major unmet need of decentralized hemoglobin analysis in resource-limited settings.

Molecular characteristics of thalassemia and hemoglobin variants in prenatal diagnosis program in northern Thailand

Molecular analysis of globin genes is an essential process for prenatal diagnosis (PND) of severe thalassemia. This study aimed to describe the molecular characteristics of thalassemia and hemoglobin (Hb) variants in PND program in northern Thailand. The type and frequency of globin gene mutations from 1290 couples at risk of fetal severe thalassemia diseases that were tested at Thalassemia Laboratory at Chiang Mai University from 2012 to 2017 were retrospectively reviewed. The PND program detected 444 (34.4%), 196 (15.2%) and 642 (49.8%) couples at risk of fetal Hb Bart's hydrops fetalis, beta-thalassemia major (BTM) and beta-thalassemia/Hb E disease, respectively. Coinheritance of more than one type of thalassemia was common and eight (0.6%) couples were at risk of two types of severe thalassemia. There were two types of alpha⁰-thalassemia; 893 (99.7%) Southeast Asian and 3 (0.3%) Thai deletions. Twenty beta-globin gene mutations were found with 94.3% of beta⁰-thalassemia. The codon 41/42 (- TTCT), codon 17 (A>T), IVS-I-1 (G>T) and codon 71/72 (+ A) comprised 90% of beta-thalassemia mutations. The study shows a high percentage of couples at risk of fetal Hb Bart's hydrops fetalis and BTM. The percentage of beta⁰-thalassemia is higher than those seen in other regions of Thailand.

Thalassemia trait and G6PD deficiency in Thai blood donors

BACKGROUND

Thalassemia trait and G6PD deficiency are asymptomatic and volunteers with these variants are eligible for blood donation.

AIMS

This study aimed to investigate prevalence and hematologic profiles of blood donors with thalassemia trait and G6PD deficiency and the influence of these abnormalities have on donor retention and blood component preparation.

METHODS

Prospectively recruited blood donors were investigated for thalassemia and G6PD deficiency. Characteristic data, hematologic profiles, proportions of prepared blood components, donor return rate within 12 months and adverse reactions in patients receiving red cell transfusions were compared among thalassemia trait, G6PD deficiency, and normal donors.

RESULTS

In Thai blood donors, thalassemia trait prevalence was 21.1% and G6PD deficiency prevalence based on G6PD activity was 7.7%. Blood donors with thalassemia trait had significantly lower hemoglobin, MCV, and MCH than blood donors without thalassemia trait (Hb 13.55 ± 1.00 vs. 13.96 ± 1.25 g/dL, MCV 76.70 ± 6.69 vs. 87.01 ± 5.10 fL, and MCH 25.06 ± 2.17 vs. 28.67 ± 1.91 pg, all respectively and all p < 0.01). However, the hematologic profiles of blood donors with G6PD deficiency were not significantly different from the hematologic profiles of blood donors with normal G6PD activity. No significant difference was observed among thalassemia trait, G6PD deficiency, and normal donors relative to donor retention and blood component preparation.

CONCLUSION

The high prevalence of thalassemia trait and G6PD deficiency in Thai blood donors observed in this study does not adversely affect donor retention and blood component preparation.

Increased Prevalence of Thalassemia in Young People in Korea: Impact of Increasing Immigration

Background

Thalassemia is highly prevalent in Southeast Asia but is rare in Korea; however, Southeast Asian immigrant population is recently rising in Korea. We investigated the prevalence of thalassemia in Korea in the context of increasing immigration.

Methods

This prospective, observational, multicenter study was conducted between September 2015 and August 2017. A total of 669 subjects <30 years living in Korea were grouped into the multiethnic (N=314) and Korean (N=355) groups. Hb electrophoresis and complete blood count (CBC) were performed. If low mean corpuscular volume with high red blood cell distribution width coefficient of variation or a high fetal Hb (HbF) or Hb alpha 2 (HbA₂) level was observed, genetic testing of the α- and β-globin genes was performed. In addition, the number of potential thalassemia carriers in Korea was estimated by multiplying the prevalence of thalassemia in a specific ethnicity by the number of immigrants of that ethnicity.

Results

Twenty-six multiethnic and 10 Korean subjects showed abnormal results for Hb electrophoresis and CBC. Eighteen multiethnic subjects and four Korean subjects were tested for α-globin and β-globin gene mutations. Within the multiethnic group, five subjects (1.5%) were α-thalassemia carriers, and six (1.9%) were β-thalassemia minor. The SEA deletion in HBA1 and HBA2, and c. 126_129delCTTT (p.Phe42Leufs*19) mutation of HBB were the dominant inherited mutations.

Conclusions

The prevalence of thalassemia in young people in Korea is increasing due to the increasing number of Southeast Asian immigrants.

ABO and Rhesus blood group distribution and frequency among blood donors at Kilimanjaro Christian Medical Center, Moshi, Tanzania

Objective

This study aims to determine the distribution of blood groups and the demographic background of blood donors in a referral hospital in Northern Tanzania.

Results

The most common blood group was O (52.3%) and the least common was AB (3.18%). 97.7% of the blood donors were Rh positive and the rest were Rh negative. Most donors were young adults, representing the age group of 19–29. The majority of donors were male (88.1%) and the majority (90.8%) were replacement while the remainder was voluntary donors.