Screening For Hemoglobinopathies Research Articles

Reemergence of Hemoglobin Yukuhashi

Abstract The abnormal hemoglobin, Hb Yukuhashi, identified in Japan in 1963, exhibits slower migration compared to Hb A and is associated with target cells on peripheral smear. A similar hemoglobin, Hb Dhofar, is found in an Omani tribesman and is defined as a substitution of arginine for proline at the 58th amino acid position of the beta-globin chain. Despite both Yukuhashi and Dhofar seemingly arising from the same exonic point mutation, variations in expression were clarified through beta-globin gene amplification. Hb Dhofar, unlike Yukuhashi, was linked to a splice-site mutation at codon 29, explaining its reduced expression. Despite these hemoglobins’ structural alterations, their functional properties on a molecular level, including oxygen affinity and heme-heme interaction, remained largely unaffected. While mutations at codon 58 have been observed alongside other mutations in Hb Dhofar and Hb C-Ziguinchor, this case represents the first sequencing and report of a beta-globin gene mutation solely at codon 58, as only Yukuhashi’s protein coding region had been sequenced, not the whole gene. “Hemoglobin D” was detected on newborn screening of a male child with no other significant medical history or physical abnormalities. Capillary Electrophoresis and Cation-Exchange HPLC showed abnormal hemoglobin fractions, with 20.1% in the S Zone and 25.7% in the D-window, respectively. This led to a presumptive diagnosis of Hemoglobin Dhofar trait; however, discrepancies in hematologic parameters and relative hemoglobin levels were noted. Genetic testing of the Beta Globin gene confirmed a C to G substitution at codon 58 but lacked the characteristic codon 29 mutations associated with Hemoglobin Dhofar. The patient, was discovered to possess a mutation at codon 58 on the beta globin gene, a mutation not previously reported in isolation. In contrast to previous studies on Hb Dhofar, where variant Hb levels were lower and accompanied by abnormal RBC indices indicative of beta thalassemia trait, this case exhibited higher variant Hb levels with normal RBC indices, suggestive of a typical beta globin variant. The mutation at codon 58 did not significantly alter intermolecular interactions of the globin which may mean the variant is clinically asymptomatic in nature. Continued follow-up is necessary to confirm this suspicion, although initial assessments at 3 and 6 months of age showed normal RBC parameters. This case represents the first instance of an isolated mutation at codon 58 of the beta globin gene, emphasizing the need to consider this mutation in interpreting hemoglobinopathy screening results.

False HbA1c value due to a rare variant of hemoglobin Petie Salpetriere coinherited with alpha thalassemia

Abstract Objectives To describe a variant hemoglobin that interferes with HbA1c analysis by cation exchange HPLC. Case presentation A 78 years-old Spanish male patient visited the Internal Medicine Clinic for a routine check-up, with HbA1c included to screen for diabetes. He had suffered hypertension and dyslipidemia, and the patient had no previous symptoms suggestive of diabetes such as hyperglycemia, weight loss, polydipsia, polyuria or tiredness. Diabetes screening by HbA1c measurement was assessed using cation exchange HPLC and an immunoassay point-of-care analyzer. Routine hemoglobinopathy screening was performed including CBC, HbF and HbA2 measurement by cation exchange HPLC and capillary electrophoresis (CE). Further variant characterization was undertaken by DNA sequencing. Discordant HbA1c results were obtained for our subject, with elevated HbA1c of 52 mmol/mol measured by cation exchange HPLC and a normal level of 34 mmol/mol by immunoassay. Abnormal HbA1c peak shape prompted hemoglobinopathy screening to investigate potential variant interference. A globin gene analysis was performed, and the results showed a variant hemoglobin named ‘Hb Petie Salpetriere’. This variant arises from a Val → Phe substitution due to a mutation of c.103G>T of the beta-globin gene [BETA34 (B16) Val>Phe; HBB:c.103G>T]. Conclusions This is the first reported case involving the Hb Petie Salpetriere variant in a Spanish patient. The present results show that the Hb Petie Salpetriere variant can affect the results of HbA1c analysis through ion-exchange HPLC, but not that obtained from the latex agglutination immunoassay. Only ion-exchange HPLC suggested the presence of the Hb variant in this case, suggesting that a careful review of the resulting chromatogram might reveal a potential variant.

Retrospective study on the distribution of hemoglobinopathies in Karnataka-A laboratory experience.

The importance of screening for hemoglobinopathies is well-documented in India. However, information on the distribution of hemoglobinopathies in Karnataka is lacking. The present study focuses on determining the spectrum of hemoglobinopathies for various districts of Karnataka. A retrospective analysis of samples registered for hemoglobinopathies for a period of 5 years (2017-2021) was carried out. A total of 17066 records registered only from the Karnataka region, were anonymized and retrieved. The data included gender, age, district, and results of the tests. The results were based on complete blood count, peripheral smear, and capillary electrophoresis (CE) pattern. The data were revalidated by pathologists, and the unambiguous data were analyzed for the study. One-fourth of the records (25%) showed abnormal hematological parameters. The number of female records (66%) was twice that of males and both genders showed higher distribution of thalassemia, followed by variants and double heterozygotes (DH). Several cases of thalassemia major were identified below the age of 17 years. The majority of thalassemia cases were β thal and 93% of them were β thal trait. Among the variants, HbS was more prevalent than HbE. Among the districts, Hassan had a 35.2% thal, Mysuru had a 7.2% variant, and Chitradurga had a 5.5% DH. Thalassemia, variants, and DH were distributed across several districts of Karnataka to various levels. The comprehensive retrospective analysis of the spectrum of hemoglobinopathies in various districts of Karnataka serves as evidence to carry out a prospective study on population screening where the incidence of thalassemia and structural variants is high.

Haemoglobinopathies and other rare anemias in Spain: ten years of a nationwide registry (REHem-AR)

REHem-AR was created in 2013. The progressive implementation of neonatal screening for haemoglobinopathies in Spanish autonomous communities where the registry had not been implemented, as well as the addition of new centres during this period, has considerably increased the sample of patients covered. In this study, we update our previous publication in this area, after a follow-up of more than 5 years. An observational, descriptive, multicentre and ambispective study of adult and paediatric patients with haemoglobinopathies and rare anaemias registered in REHem was performed. The data are from a cross-sectional analysis performed on 1 June, 2023. The study population comprised 1,756 patients, of whom 1,317 had SCD, 214 had thalassaemia and 224 were diagnosed with another condition. Slightly more than one third of SCD patients (37%) were diagnosed based on neonatal bloodspot screening, and the mean age at diagnosis was 2.5 years; 71% of thalassaemia patients were diagnosed based on the presence of anaemia. Vaso-occlusive crisis and acute chest syndrome continue to be the most frequent complications in SCD. HSCT was performed in 83 patients with SCD and in 50 patients with thalassaemia. Since the previous publication, REHem-AR has grown in size by more than 500 cases. SCD and TM are less frequent in Spain than in other European countries, although the data show that rare anaemias are frequent within rare diseases. REHem-AR constitutes an important structure for following the natural history of rare anaemias and enables us to calculate investment needs for current and future treatments.

New Born Screening of Hemoglobinopathies in a Center Tunisian Population.

Sickle cell diseases, β-thalassemia, and other hemoglobinopathies are common in Africa. Their distribution differs from one region to another. There are higher frequencies in Western and Northern Africa. Their clinical complications presented a real public health problem in each country. For this, early treatment can improve the severity of these diseases. Hemoglobinopathies targeted by screening are associated with SCD, β, and α thalassemia. Our study aim is to report our experience with newborn screening for hemoglobinopathy in Tunis. The 156 newborn's cord blood was collected at the time of childbirth in the center region (Farhat Hached Hôspital). We opted for hemoglobin exploration to achieve maximum efficiency and effectiveness in screening. After that, all patients suspected to have hemoglobinopathies are affected by molecular investigation. Our findings showed the presence of some hemoglobinopathies such as β-thalassemia and α-thalassemia with the following frequencies: 12% and 0.33%. The molecular results show the presence of HBB: c.93-21G>A, IVS-I-110G>A, HBBc. -106G>A -56G>C, HBBc.404T>C, Hb Yaounde described for the first time in Tunisia and α 3,7 . In conclusion, newborn screening diagnoses neonates with different examples of hemoglobinopathies, which will be beneficial not only for the care of the child but also for genetic counseling of the potential risk's parents.

Comparison of High-Performance Liquid Chromatography and Capillary Electrophoresis in the Screening of Haemoglobinopathies

Comparison of High-Performance Liquid Chromatography and Capillary Electrophoresis in the Screening of Haemoglobinopathies

Hemoglobin Variants in Patients Attending Aden Diagnostic Center by High Performance Liquid Chromatography

Introduction: High performance liquid chromatography (HPLC) is emerging as the method of choice for initial screening and diagnosis of hemoglobinopathies. The use of alkaline and acid gel electrophoresis may result in incorrect diagnosis of hemoglobinopathies. The aim of the study is to investigate the hemoglobin pattern using the HPLC and to correlate the hematological profile with the types of hemoglobin. Methods: A cross-sectional study was conducted in Aden Diagnostic Center from July– December 2022. Over a six-month period, 250 samples of patients aged between six months to thirty years, were evaluated by HPLC for detection of hemoglobinopathies using the Lifotronic Hemoglobin Analyzer H9: β-thalassemia Analysis Mode. Red blood cell and red cell indices were determined using automated hematology analyzer. Results: A total of 152 samples (60.8%) showed different abnormal hemoglobin variants. Sixty-four (25.6%) were diagnosed to have sickle cell anemia, 46 (18.4%) as sickle cell trait, two (0.8) as beta – heterozygous thalassemia based on high level of HbA2 (>3.9%), four (1.6%) as beta – homozygous thalassemia (HbF 25–91%), 18 (7.2%) as compound heterozygous state of sickle - β+ thalassemia, 17 (6.8%) as beta thalassemia trait, and one (0.4%) sample had HbD variant on HPLC was diagnosed as HbD trait. Conclusion: H9-HPLC is suitable for the routine investigation of hemoglobinopatheis because it is very powerful tool in the evaluation of Hb variants, rapid assay time and accurate quantification.

Iowa Newborn Screening Program Experience with Hemoglobinopathy Screening over the Last Two Decades and Its Increasing Global Relevance.

Hemoglobinopathies are the commonest monogenic disorder worldwide, with approximately seven percent of the world population being carriers of hemoglobinopathies. The healthcare utilization impact of thalassemia has resulted in global public health initiatives to screen for hemoglobinopathies, especially sickle cell disease (SCD). The Iowa Newborn Screening Program (INSP) has been in place for more than 50 years with a primary focus on detecting SCD. Recent changes in migration patterns have led to a global distribution of hemoglobinopathies in the western world, which has translated to an increase in the diagnosis of SCD and the incidental detection of non-sickling hemoglobinopathies within the INSP. This study documents the birth prevalence of hemoglobinopathies diagnosed in newborns through the INSP and highlights the need for newborn screening programs to evolve to meet the healthcare needs of underserved, minority populations.

Screening for Hemoglobinopathies in Pregnant Women of Haroti Region: A Guide for Surveillance, Diagnosis and Prevention

Screening for Hemoglobinopathies in Pregnant Women of Haroti Region: A Guide for Surveillance, Diagnosis and Prevention

Significance of premarital screening and genetic counselling program for hemoglobinopathies

Introduction: Premarital screening includes general medical examination by which the promotion of a woman's and her partner's health and well-being prior to conception. It is regarded as a primary preventive approach for couples planning to conceive, as well as an important step toward protecting society of disease's spread. Hemoglobinopathies are one of the most frequent autosomal recessive illnesses in Iraq, which may associate with significant mortality and morbidity. Its inherited disorders and run down through families. Humans are affected by this disorder, which can occur due to the presence of quantitative and, or qualitative irregularities in the globin chains. Hemoglobin (Hb)S, which causes sickle cell disease (SCD), Hb-C or Hb-D illness, and other qualitative abnormalities, is the most prevalent. α- and β-thalassemia are quantitative anomalies with reduced or missing production of β or α globin chains are the most common. The world's most common single-gene diseases, particularly in the Eastern Mediterranean region, which includes Iraq Conclusion :All of the above data support the concept of a haemoglobinopathies prevention program based on premarital screening, counseling, and prenatal diagnosis with the aim of decrease the number of afflicted children born in the region

Premarital screening of haemoglobinopathies: Experience of the major centre of Diyala Governorate, Iraq

Premarital screening of haemoglobinopathies: Experience of the major centre of Diyala Governorate, Iraq

359 Hemoglobinopathy screening in the era of expanded carrier screening: is hemoglobin electrophoresis necessary?

359 Hemoglobinopathy screening in the era of expanded carrier screening: is hemoglobin electrophoresis necessary?

Bridging the gaps in newborn screening programmes: Challenges and opportunities to detect haemoglobinopathies in Africa.

Haemoglobinopathies, including sickle cell disease and β-thalassaemia, are monogenic disorders with a relatively higher prevalence among malaria-endemic areas in Africa. Despite this prevalence, most African countries lack the necessary resources for diagnosing and managing these debilitating conditions. This study provides a critical review of newborn screening for detecting haemoglobinopathies in Africa, highlighting challenges and proposing strategies for improved diagnosis and management. A literature search on haemoglobinopathies in Africa was conducted in PubMed, Google Scholar and ScienceDirect, using specific keywords and Boolean operators, including articles published from January 1981 to December 2022. The data show that sickle cell disease is prevalent among populations in Central and West Africa; however, β-thalassaemia is prevalent among people in the northern parts of Africa. Newborn screening pilot initiatives for haemoglobinopathies were being implemented in Angola, Nigeria, Ghana, the Democratic Republic of Congo and the Republic of Benin. The cost of testing, lack of sufficient and accessible medical records, and inadequacy in healthcare infrastructure pose significant challenges in bridging the gaps in newborn screening. Furthermore, the stigmatisation and lack of awareness of haemoglobinopathies and access to newborn screening programmes pose additional challenges. This review highlights the challenges associated with haemoglobinopathy testing, effective strategies for mitigating these challenges, and future perspectives for expanding efforts toward detecting and managing these disorders across Africa. Providing affordable diagnostic tools, mobile clinics, government subsidies, education campaigns, and the implementation of electronic medical records systems could help bridge the gaps in newborn screening in Africa. The study presents a comprehensive view of newborn screening of haemoglobinopathies in Africa, provides a detailed outline of the challenges faced by newborn screening for haemoglobinopathies in Africa, and offers strategies for better diagnosis and care.

Premarital hemoglobinopathy screening program results of a province in the Black Sea region of Turkey: three years’ experience

ABSTRACT Objectives Hemoglobinopathies are a global public health problem with high mortality and morbidity and very expensive treatment. Disease can be reduced and prevented with hemoglobinopathy screening tests. It is possible to identify carriers with the hemoglobinopathy screening program applied in many countries of the world and in Turkey. This study aims to evaluate the results of the national premarital hemoglobinopathy screening program carried out in primary healthcare institutions. Methods The research is of epidemiological and cross-sectional type. Electrophoresis results examined within the scope of the premarital hemoglobinopathy screening program in Samsun between 1 January 2019 and 31 December 2021 were evaluated retrospectively. Age, gender, year of screening, and hemoglobinopathy screening results were obtained from the records. In the statistical analysis of the data, p < 0.05 was accepted. Results The median age of 52,338 people screened under the hemoglobinopathy screening program was 29.0 (16.0–86.0) years. About 54.1% (n = 28,309) of those who were screened were female, and it was found that the least screening was done in 2020 (n = 15,765 (30.1%)). As a result of the screening, the frequency of the β-thalassemia (β-thal) trait was 1.37% (n = 676), the frequency of the abnormal HbS was 0.04% (n = 20). The frequency of β-thal trait was statistically significantly higher in 2020 (1.5%) compared to other years (p = 0.029). When the results were analyzed by gender, the rate of women with abnormal HbS (3.7%) was significantly higher than the others (p = 0.017). Conclusions This study presents the results of the national hemoglobinopathy screening program in Northern Turkey and the β-thal and the abnormal HbS rates were found to be low. The data obtained will be useful in monitoring hemoglobinopathy disorders and evaluating the current program’s effectiveness in the future. It will allow decision-makers to implement policy changes and prioritize new programs.

Lessons learnt in the screening and diagnosis of haemoglobinopathies.

For this paper, cases reported formally and anecdotally to the authors in their screening and diagnostic roles have been selected to demonstrate areas where errors have occurred, and caution should be exercised. The cases demonstrate that it is vital that the performance and limitations of the techniques used, along with the phenotypic presentation of cases where haemoglobin variants and/or thalassaemias are coinherited are understood by those performing result interpretation. Those who deliver the service as well as those who receive reports and give results and counselling should be aware of the complexity of the topic.

Direct cord blood LAMP colorimetric phenol red assay for detecting α0-thalassemia (SEA deletion); the validation and post-natal screening in Thailand

Post-natal or newborn screening for thalassemia and hemoglobinopathies is useful for genetic counseling and managing thalassemia in children. We characterized thalassemia genotypes in newborns from the eastern part of Thailand. The results demonstrated a high heterogeneity of thalassemia and hemoglobinopathies with seventeen genotypes. We focused on α0- thalassemia (Southeast Asian [SEA] deletion) in this study. We developed and validated the loop-mediated isothermal amplification (LAMP) colorimetric assay for detecting α0- thalassemia (SEA deletion) using simple direct cord blood sampling compared to genomic DNA. A total of 160 cord blood samples were evaluated with the LAMP assay. The sensitivity and specificity of the LAMP colorimetric assay for α0-thalassemia (SEA deletion) using direct cord blood showed 100% (6/6 x 100) and 98.05% (151/154 x 100) whereas, genomic DNA showed 100% (6/6 x 100) and 100% (154/154 x 100), respectively. Moreover, we demonstrated other simple screening tools for α0-thalassemia with %Hb Bart’s, MCV, and MCH values and found that these parameters were not diagnostic in our samples. The direct cord blood with colorimetric LAMP assay is simple, rapid, and does not require a post-LAMP step compared to conventional PCR. These techniques could be applied in post-natal or large population screening for α0-thalassemia (SEA deletion). Finally, this could support early prevention of complications, early management, genetic counseling for α-thalassemia disease in children, or a long-term prevention and control program of severe thalassemia in Thailand.

Screening for haemoglobin disorders: One size may not fit all.

Accurate laboratory screening for sickle cell disease and other haemoglobin disorders is expanding worldwide. Two new reports describe different methods and strategies for screening in Mali and Denmark, respectively, and their encouraging results suggest that countries should tailor their screening programmes according to local needs, resources and opportunities. Commentary on: Guindo et al. Potential for a large-scale newborn screening strategy for sickle cell disease in Mali: a comparative diagnostic performance study of two rapid diagnostic tests (SickleScan® and HemotypeSC®) on cord blood. Br J Haematol 2024;204:337-345 and Gravholt et al. The Danish national haemoglobinopathy screening programme: report from 16 years of screening in a low-prevalence, non-endemic region. Br J Haematol 2024;204:329-336.

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

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

Homozygous delta beta-thalassemia: A rare case report

Delta Beta (δβ) thalassemia is a rare autosomal recessive hemoglobinopathy. This is caused by either reduced production of δ and β genes (heterozygous state) or complete absence (homozygous state). High-performance liquid chromatography (HPLC) is an important screening and diagnostic tool, to be supported by molecular data and parental studies. A 40-year-old male (propositus), with mild anemia presented in the outpatient department. There were no other definitive causes of anemia with adequate nutritional status and no response after the treatment with nutritional supplements. HPLC was advised to look for any qualitative/quantitative defects. HPLC findings reveal 96% fetal hemoglobin (HbF), a very small quantity of adult hemoglobin (HbA), and an absent HbA2. In view of this data, followed up with parental studies. Both parents had elevated HbF and similar grades of anemia. These supported the presence of a heterozygous state of δβ-thalassemia in parents and homozygous δβ thalassemia in propositus. In δβ-thalassemia, there is a deletion of the δ and β genes on Chromosome 11. Expression of the gamma gene increases to compensate, causing increased production of gamma globulin for HbF (α2 β2). On HPLC or electrophoresis, heterozygosity shows as normal HbA2 and elevated HbF, and as absent HbA2 with almost 100% HbF for homozygous individuals. Screening of hemoglobinopathies by HPLC is that can be further subjected to parental screening for a more definitive diagnosis and narrow down the differentials as compared to molecular testing considering the cost, limited availability, and higher turnaround time.

Incidental finding of rare hemoglobin: hemoglobin Bari in northeast Spain

Abstract Objectives Cation exchange high-performance liquid chromatography (HPLC) is one of the techniques available for determining glycated hemoglobin (HbA1c) and also the method of choice for structural hemoglobinopathies screening. The objective of this case is to show how in a routine HbA1c test it is possible to incidentally find a hemoglobinopathy. Case presentation In a routine blood analysis, an abnormal value for the hemoglobin A2 (HbA2) was obtained during the study of HbA1c with HPLC on the ADAMS™ A1c HA-8180T. After suspecting it could be due to the presence of a hemoglobinopathy, the study of possible variants was expanded using electrophoresis and HPLC on the Hydrasys and Variant II analysers, respectively. Since it could not be identified by these conventional methods, a genetic study was also carried out using Sanger sequencing. The patient presented a low HbA2 (1.3 %) and a 24.9 % variant with a retention time of 1.95 min, compatible with alpha-globin chain variant. In the genetic study, the pathogenic variant c.138C&gt;G was detected in the HbA 2 gene in heterozygosis, which resulted in the expression of the structural hemoglobinopathy known as hemoglobin Bari. Conclusions The initial screening for structural hemoglobinopathies allows its identification or suspicion especially when it was performed with HbA1c analysis, requiring subsequent confirmation and diagnosis by other techniques.