Screening For Hemoglobinopathies Research Articles

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>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.

Thalassemia and Hemoglobinopathy Screening in Women Attending Antenatal Clinic at a Tertiary Care Center in Uttarakhand, India: A Re-look at the Laboratory Parameters Mandating High-Performance Liquid Chromatography Workup.

Thalassemia and hemoglobinopathies are the most common inherited hematological disorders. Of these, β thalassemia is the commonest disorder reported in India, followed by certain hemoglobinopathies encountered in different regions of the country. The data pertaining to the incidence of these disorders in the Uttarakhand region of India are sparse. To ascertain the prevalence and spectrum of thalassemia/hemoglobinopathies amongst antenatal women in Uttarakhand. The study also aimed to analyze the ability of red cell indices in differentiating beta thalassemia trait (BTT) from mild iron deficiency anemia (IDA). A total of 460 pregnant women in the first trimester of pregnancy were screened by cation exchange high-performance liquid chromatography. Retention time and proportions of normal/abnormal hemoglobin peaks were documented in all cases. Hemoglobin A2 (HbA2) values of ≥4% were taken as a cut-off for diagnosing BTT. Blood samples were also collected for complete blood counts, reticulocyte counts, and serum ferritin. The ability of the various discriminatory indices to differentiate between IDA and BTT was also assessed. The prevalence of BTT and hemoglobin D-Punjab trait amongst pregnant women was found to be 2.6% and 0.2%, respectively. RBC count, mean corpuscular volume (MCV), and mean corpuscular hemoglobin (MCH) were found to be moderately strong predictors of BTT, with an area under the curve of 0.860, 0.857, and 0.842, respectively, which were comparable to the discriminatory indices found to be most useful in this study. In view of the 2.6% prevalence of BTT in antenatal women in this region of Uttarakhand, a routine screening will be helpful in detecting carriers early in the antenatal period. Careful interpretation of red cell indices is crucial to the distinction between BTT and IDA. Discriminatory indices are reasonably accurate in differentiating BTT from mild iron deficiency, but for practical purposes, MCV and MCH provide equivalent information to identify cases that require further workup.

Nanopore Third-Generation Sequencing for Comprehensive Analysis of Hemoglobinopathy Variants.

Oxford Nanopore Technology (ONT) third-generation sequencing (TGS) is a versatile genetic diagnostic platform. However, it is nonetheless challenging to prepare long-template libraries for long-read TGS, particularly the ONT method for analysis of hemoglobinopathy variants involving complex structures and occurring in GC-rich and/or homologous regions. A multiplex long PCR was designed to prepare library templates, including the whole-gene amplicons for HBA2/1, HBG2/1, HBD, and HBB, as well as the allelic amplicons for targeted deletions and special structural variations. Library construction was performed using long-PCR products, and sequencing was conducted on an Oxford Nanopore MinION instrument. Genotypes were identified based on integrative genomics viewer (IGV) plots. This novel long-read TGS method distinguished all single nucleotide variants and structural variants within HBA2/1, HBG2/1, HBD, and HBB based on the whole-gene sequence reads. Targeted deletions and special structural variations were also identified according to the specific allelic reads. The result of 158 α-/β-thalassemia samples showed 100% concordance with previously known genotypes. This ONT TGS method is high-throughput, which can be used for molecular screening and genetic diagnosis of hemoglobinopathies. The strategy of multiplex long PCR is an efficient strategy for library preparation, providing a practical reference for TGS assay development.

Comparison of HbA2 Using High Performance Liquid Chromatography Versus Haemoglobin Capillary Zone Electrophoresis.

Thalassemia is among the most common hereditary disorders in the world. Approximately 5% of the world's population are carriers of hemoglobinopathies, and 2.9% are carriers of beta thalassemia. Haemoglobin A2 (HbA2) constitutes less than 3% of the total hemoglobin (Hb) in adults, and the determination of Hb A2 levels is important to diagnose the beta thalassemia trait(BTT). In some cases, the level of HbA2 is not typically elevated, and some difficulties may arise in making the diagnosis. Cation exchange high-performance liquid chromatography (HPLC) and HbCZE (haemoglobin capillary zone electrophoresis) are considered acceptable methods to diagnose BTT, but these vary in their accuracy and cut-offs. In this study, we attempted to compare HbA2 values using two methods, HPLC and HbCZE, in 536 whole blood samples sent by physician-ordered hemoglobinopathy screening over two years. This included antenatal women, patients with anemia not responding to iron, and cases of familial screening where either a child or a sibling had been diagnosed with hemoglobinopathy or thalassemia. The performance characteristics of both machines were compared for the detection of the 5 most common hemoglobin variants: Hb A, HbF, HbS, Hb C, and HbE. On comparing the HbA2 values, the HPLC showed higher values for HbA2 as compared to HbCZE, while the HbF and HbS measurement agreement was good between both methods. Normal ranges and mean normal values of HbA2 differ between different methods and different manufacturers; hence, each institute using these machines should validate its cutoffs.

5613304 ANTENATAL SCREENING FOR HAEMOGLOBINOPATHIES AMONG THE TRIBAL POPULATION IN THE STATE OF TAMIL NADU, INDIA

Background: Hemoglobinopathies especially Sickle cell anemia and Thalassemia is more prevalent in the tribal population living in the hilly areas of Tamilnadu. As a part of the Government initiative for prevention of hemoglobinopathy, National Health Misiion, Tamilnadu State Chapter, has initiated Hemoglobinopathy screening for antenatal mothers in this target population. It was anticipated to have challenges like difiiculites in convincing the families for screening and if required aminocentesis. The study details with results of this screening program conducted over the period of 9 months is being presented. The project is ongoing till date. Aim: To prevent the prospective birth of Thalassemia and Sickle Cell Anemia children in Hemoglobinopathy prevalent tribal population Study Period: From September 2021 to June 2022 Methodology: All Antenatal Mothers attending the Primary health centres (PHC - Government Health Facilities) in 18 tribal blocks were screened for Haemoglobinopathies (Thalassemia & SCA) during the first trimester. 4 ml of blood was taken, 2 ml each in EDTA tubes. Informed consent was obtained before taking blood samples for test. Complete Blood Count was done in the Primary Health Centre. The second sample was transported under cold chain to the nearest medical college on the same day where high performance liquid chromatography (HPLC) was done. The CBC reports of all the mothers screened were shared with the Biochemistry Department where HPLC was done in the Biorad - 10 machine. If the mothers were found to have Thalassemia or Sickle Cell trait, husbands were tested for CBC & HPLC. If the couple was positive they were given genetic counselling regarding amniocentesis at the PHC with online support of specialists including Hematologist, State Blood Diseases Expert, and Genetics Consultant. If the couple give their consent, amniocentesis was done between 16 – 20 weeks at the prenatal diagnostic centre at state Capital, Chennai. Genetic testing was done for the parents and the foetus. This test was outsourced. If the foetus was found to be affected post test counselling was given regarding Medical Termination of Pregnancy (MTP) if they gave consent MTP was done. If the foetus was normal or to have trait, pregnancy was continued. Results: Total Mothers screened - 14016 Antenatal (AN) mothers Prevalence of Hemoglobinopathy Trait/ diseased - 7 % (959) Various types of Hemoglobinopathy trait/ diseased among the screened AN Mothers - Thalassemia trait (40.8%), Sickle cell trait (27.6 %), Sickle Cell Anemia (2%), Borderline thalassemia trait (29.6 %) No of husbands screened 511 out of which 13 % (73) were positive No of Amniocentesis done in 38 antenatal mothers out of which 31.58 % (12) were normal foetus, Trait Foetus 47.37 % (18), affected & MTP done 21.05 % (8) Conclusion: Antenatal Screening & Diagnosis is the best strategy for preventing Haemoglobinopathies which will be cost effective in the long term. It proactively reduces morbidity, mortality, DALY & psychological problems seen in management of affected children & their families. The direct medical cost of treating 1 Thalassemia child weighing 30 kg is around 2500 USD per year along with significant indirect expenses where as the cost of Antenatal Screening & Prenatal Diagnosis is 225 USD. The challenges met in implementing the program including difiiculty in taking the husband’s sample and counseling the couple with affected fetus are addressed. Reference 1. S Chakravorty, MC Dick. Antenatal Screening for Heamoglobinopathies; current status, barriers and ethics. Br J Haematol 2019; 187(4):431-440. doi: 10.1111/bjh.16188. Epub 2019 Sep 11.

Optimising the screening for haemoglobinopathies in pregnancy planning

Haemoglobinopathies are among the most common inherited disorders around the world. In the United States the diagnosis of haemoglobinopathy or a carrier state is made by universal newborn screening. However, many individuals of childbearing age do not know they are a haemoglobinopathy carrier. Screening for common haemoglobinopathies is generally offered as a part of pregnancy planning so that prospective parents can be counselled regarding the risk of having a child with a haemoglobinopathy. Multiple tests exist to screen patients for presence of haemoglobinopathy carrier or disease state; however, it is crucial to order and interpret the results correctly to appropriately counsel couples. In this case series, we describe clinical scenarios where prospective parents were surprised to unexpectedly have a child with sickle cell disease, a haemoglobinopathy that causes severe clinical complications. Through these cases we demonstrate that deficiencies in testing can occur at different levels which may lead to incorrect estimation of the risk of having a child affected by a haemoglobinopathy. Consultation with a haematologist, laboratory medicine specialist, or genetic counsellor should be considered to select the appropriate test and interpret its results.

EVALUATION OF MICROCYTIC HYPOCHROMIC ANEMIA BY ELECTROPHORESIS FOR HEMOGLOBINOPATHIES IN YOUNG POPULATION

Objectives: Hemoglobinopathies are serious genetic blood disorders requiring lifelong blood transfusions and treatment in its most severe and chronic form. If undiagnosed or untreated, these disorders ultimately lead to death. South Asia especially India, Pakistan, and Bangladesh has high populations of hemoglobinopathies. In India, there are an estimated 100,000 thalassemia majors patients and nearly 3.5 to 4 million carriers of this genetic disorder. Tribal populations in India have a range of 5–40% sickle cell anemia (SCA) sufferers. The aim of the study was to detect hemoglobinopathies by electrophoresis in microcytic hypochromic anemia in young population in the area covered by tertiary care center at Index Medical College and Hospital. Methods: A cross-sectional study was carried out in a hospital in rural area of Indore on young patients (10–30 years age group) who attended outpatient department from June 2018 to March 2020. Total 517 cases of moderate to severe anemia were included in the study. All cases were subjected to a series of hematological investigations, which include complete hemogram, peripheral blood smear, and some standard procedures. Sysmex XS800i fully automated Cell counter was used for complete blood count. It is the 5-part differential instrument. It reports on all the five subpopulations, namely, neutrophils, eosinophils, basophils, monocytes, and lymphocytes. A blood smear is a blood test used to look for abnormalities in blood cells. Results: In the study, out of 517 cases 34.4% cases were positive on Hb electrophoresis and 65.6% were negative. On electrophoresis, the number of sickle cell anemia cases was 34.3%, sickle cell trait – 20.8%, sickle beta-thalassemia – 29.8% and beta-thalassemia major – 29.8% was observed. In hemoglobinopathies, of the 73 females, 28.8% were having beta-thalassemia trait, 27.4% were having SCA 23.3% were having sickle beta-thalassemia, and 20.5% were having sickle cell trait. Of the 105 males, 30.5% were having beta-thalassemia trait, 9.5% were having sickle beta-thalassemia, 39.0% were having SCA, and 21.0% were having sickle cell trait. Conclusion: The ANMs, ASHA, and Anganwadis should be taught about the importance of screening of hemoglobinopathies. So that they can explain the purpose of screening to the female during pregnancy and to the families in the rural areas. At primary level, the CHCs and PHCs should be equipped with instruments for basic testing of hemoglobinopathies.

Role of premarital screening program in detection of hemoglobinopathies at Al Baha, Saudi Arabia

Background: Hemoglobinopathies are prevalent in Saudi Arabia. The use of high-performance liquid chromatography (HPLC) for screening of these disorders has recently been undertaken. This study was conducted to estimate the prevalence of hemoglobinopathies and evaluate the role of premarital screening centers among residents of Al Baha province, Saudi Arabia. Methods: This retrospective cohort study utilized the laboratory reports of couples attending the premarital screening centers for the screening and confirmation of hemoglobinopathies in Al Baha province, Saudi Arabia. We obtained data from four hospitals and three primary healthcare centers authorized to perform these screening tests. Results: The current study screened and analyzed a total of 2,165 reports for suspected hemoglobinopathies. Only 121 (5.6%) reports showed abnormal hemoglobin (Hb) patterns, among which the sickle cell trait was the most common, representing 59.5% (72/121) of the reported cases. This was followed by the β-thalassemia trait, Hb Lepore, sickle cell disease, and β-thalassemia major, accounting for 32.2% (39/121), 3.3% (4/121), 2.5% (3/121), and 2.5% (3/121), respectively. Conclusion: Sickle cell and β-thalassemia traits are the major hemoglobinopathies in Al Baha, Saudi Arabia. Premarital screening is an invaluable measure to prevent childbirth with severe Hb disorders. The use of HPLC in the screening process provides a rapid, reliable procedure for the identification of various Hb fractions.

Hematological Parameters and Demographic Distribution of Hemoglobinopathies and Various Hemoglobin Variants.

Background The study was conducted to find the prevalence of hemoglobinopathies along with their geographical/ethnic distribution to highlight the region of high prevalence that can be used to guide screening. Method Results of blood samples received for hemoglobin variants determination by high-performance liquid chromatography (HPLC) were retrospectively analyzed at Shaukat Khanum Memorial Cancer Hospital and Research Centre, Lahore. Blood samples were assayed for CBC (complete blood count), red blood cell morphology, and hemoglobin analysis by HPLC. CBC was performed on Sysmex XN 9000 analyzer (Sysmex, Kobe Japan), peripheral smears to review RBC morphology were stained with Wright-Giemsa stain, and HPLC was performed on BIO-RAD variant II (Bio-Rad Laboratories, Hercules, USA). Results Hemoglobinopathies were identified in 9.7% (n=997) out of 10,297 samples. Beta thalassemia trait was the most common hemoglobinopathy recognized with a prevalence of 5% (n=516), with the maximum number of cases in the Lahore district of Punjab province. The next most common hemoglobinopathy identified was sickle cell disease with a frequency of 1.43% (n=148) and the maximum cases from the Dera Ismail Khan district of the Khyber Pakhtunkhwa province. The additional important hemoglobinopathies found were sickle cell trait, hemoglobin-D Punjab trait, and compound heterozygote for sickle and beta thalassemia. Conclusion Hemoglobinopathies are the most common inherited disorders in Pakistan and worldwide. Screening for hemoglobinopathies is recommended in high-prevalence districts of Pakistan. Sickle cell screening is also recommended in newborns in the high prevalence area of Pakistan, such as the northwest regions.

Basic biochemical and hematological parameters of structural hemoglobin variants in the postpartum women and their respective newborn from Manaus, Amazonas, Brazil

The present study aimed at estimating the prevalence of structural hemoglobinopathies in newborn and describing the hematological and biochemical characteristics between postpartum women (PW) and their respective newborns (NB) at a public maternity hospital in Manaus, Amazonas state, Brazil. In total, 825 NB and 820 PW were included in the study. Hematological and biochemical analysis and screening of structural hemoglobinopathies were performed and compared in groups of individuals (NICU or not; hemoglobin genotypes; gestational age and prenatal). The age of PW ranged from 13 to 44 years old (mean of 23.7 ± 6.6 years), with 45.9% pregnant for the first time and 54.1% multiparous. Reported receiving prenatal care 88% and regarding the type of delivery, 47.7% had delivered by cesarean section. Among the births, 19.4% were born premature and 8.3% were admission to the neonatal intensive care unit (NICU). The male NB represented 53.4% of the total. Sickle cell trait (FAS) was found in 16 (1.94%) and heterozygous for D hemoglobin (FAD) in 6 (0.73%) newborns. A statistically significant values was found between the previous history of miscarriage and increase of Mean corpuscular volume (MCV) (p < .001), Red blood cell distribution width (RDW) (p = .003), total and indirect bilirubin concentration (p < .001) and LDL cholesterol (p = .004). Hemoglobin levels below 13.5 g/dL was found in 66% black newborns, compared with 15% of Afro-Brazilian and 5% of whites. The frequency of structural hemoglobinopathies was higher in African-Brazilian newborn babies (78%) and those who with low birth weight had a higher frequency of NICU (35.7%). Interestingly, underage mothers had a higher frequency of NB with low birth weight and premature birth. Postpartum women who had children carriers of FAS and FAD had a higher frequency of urinary tract infection (65.2%) and moderate anemia (23.8%). This study estimated for the first time the prevalence of structural hemoglobinopathies in NB in Manaus, Amazonas, Brazil. Despite the small prevalence of, we highlight the importance of early diagnosis of hemoglobin variants, contributing to the improvement of the quality of life of PW and your NB, reinforce the need to implement educational and prevention programs to raise awareness among the population and in order to counsel parents regarding the probability of having a child with abnormal hemoglobins homozygous as HbSS or HbCC.

Maternal carrier screening with single-gene NIPS provides accurate fetal risk assessments for recessive conditions

PurposeThe purpose of this study was to evaluate the clinical performance of carrier screening for cystic fibrosis, hemoglobinopathies, and spinal muscular atrophy with reflex single-gene noninvasive prenatal screening (sgNIPS), which does not require paternal carrier screening. MethodsAn unselected sample of 9151 pregnant individuals from the general US pregnant population was screened for carrier status, of which 1669 (18.2%) were identified as heterozygous for one or more pathogenic variants and reflexed to sgNIPS. sgNIPS results were compared with newborn outcomes obtained from parent survey responses or provider reports for a cohort of 201 pregnancies. ResultsOverall, 98.7% of pregnant individuals received an informative result (no-call rate = 1.3%), either a negative carrier report or, if identified as heterozygous for a pathogenic variant, a reflex sgNIPS report. In the outcomes cohort, the negative predictive value of sgNIPS was 99.4% (95% CI = 96.0%-99.9%) and average positive predictive value (PPV) of sgNIPS was 48.3% (95% CI = 36.1%-60.1%). Importantly, personalized PPVs accurately reflected the percentage of affected pregnancies in each PPV range, and all pregnancies with a sgNIPS fetal risk of >9 in 10 (90% PPV) were affected. ConclusionAlthough traditional carrier screening is most effective when used to assess reproductive risk before pregnancy, more than 95% of the time it is pursued during a pregnancy and is complicated by incomplete uptake of paternal carrier screening (<50%) and misattributed paternity (∼10%). Even in an idealized setting, when both partners have carrier screening, the maximum risk for having an affected pregnancy is 1 in 4 (equivalent of a 25% PPV). Carrier screening with sgNIPS during pregnancy is an alternative that does not require a paternal sample and provides accurate fetal risk in a timely manner that can be used for prenatal counseling and pregnancy management.

An efficient isoelectric focusing of microcolumn array chip for screening of adult Beta-Thalassemia

Traditional capillary isoelectric focusing (cIEF), liquid chromatography (LC) and capillary zone electrophoresis (CZE) still suffered from low resolution for hemoglobinopathy screening. Herein, a 30-mm pH 5.2–7.8 microcolumn IEF (mIEF) array chip was developed for hemoglobinopathy screening. As a proof of concept, adult beta-thalassemia was chosen as a model disease. In the method, blood samples were hemolyzed via hemolysin solution and loaded into the microcolumn. The experiments showed that (i) the species of Hb A, F, A2 and variants were clearly separated in the chip, and the resolution was greatly higher than the ones of LC/CZE/cIEF; (ii) up to 24 samples could be simultaneously analyzed in 12-min run; (iii) the intraday and interday RSDs were respectively 3.32–4.91 % and 4.07–5.33 %. The assays of mIEF to total 634 samples were compared with the ones of LC (n = 327) and PCR (n = 307). The cutoff of 3.5 % HbA2 led to the sensitivity of 100 % and specificity of 89.1 % for the mIEF-based screening; and there was 96.7 % coincidence between the methods of mIEF and PCR if refer Hb A2 and F. The method had the merits of facility, efficiency, specificity and sensitivity in contrast to the currently-used methods, implying its potential to screening of beta-thalassemia and hemoglobinopathies.

The Consortium on Newborn Screening in Africa for sickle cell disease: study rationale and methodology

AbstractSickle cell disease (SCD) is a common condition within sub-Saharan Africa and associated with high under-5 mortality (U5M). The American Society of Hematology instituted the Consortium on Newborn Screening in Africa (CONSA) for SCD, a 7-country network of sites to implement standardized newborn hemoglobinopathy screening and early intervention for children with SCD in sub-Saharan Africa. CONSA’s overall hypothesis is that early infant SCD screening and entry into standardized, continuous care will reduce U5M compared with historical estimates in the region. Primary trial objectives are to determine the population-based birth incidence of SCD and effectiveness of early standardized care for preventing early mortality consortium-wide at each country’s site(s). Secondary objectives are to establish universal screening and early interventions for SCD within clinical networks of CONSA partners and assess trial implementation. Outcomes will be evaluated from data collected using a shared patient registry. Standardized trial procedures will be implemented among designated birth populations in 7 African countries whose programs met eligibility criteria. Treatment protocol includes administering antibacterial and antimalarial prophylaxis and standard childhood vaccinations against infections commonly affecting children with SCD. Infants with a positive screen and confirmation of SCD within the catchment areas defined by each consortium partner will be enrolled in the clinical intervention protocol and followed regularly until age of 5 years. Effectiveness of these early interventions, along with culturally appropriate family education and counseling, will be evaluated by comparing U5M in the enrolled cohort to estimated preprogram data. Here, we describe the methodology planned for this trial.

Antenatal screening for hemoglobinopathies with HPLC and their fetomaternal outcome

Introduction: Hemoglobinopathies are diverse group of inherited disorders of hemoglobin production and function. They represent the most common single-gene disorders that are found in humans and are distributed in various frequencies throughout the world. Pregnancy in women with sickle cell disease can increase the risk of maternal and perinatal mortality. HPLC offers the advantages over the routine Hemoglobin electrophoresis as it can more accurately identify and quantitate abnormal hemoglobin. HPLC forms an accurate, rapid and reproducible tool for early detection and management of thalassemia and abnormal hemoglobin variants. Material and Methods: This is an observational study was undertaken in the Department of Obstetrics &amp; Gynaecology and Department of Hematology of S.C.B Medical College, Cuttack. During this period those pregnant women, who attended gynaecology OPD of SCB medical college, Cuttack were investigated during various months of gestations. All pregnant women were counselled and offered screening for hemoglobinopathies after informed and written consent. Results: Among the antenatal women with hemoglobinopathy, 90.91% were anemic, 09.09% were not anemic. Among the normal group 71.06% were anemic, 28.94% were not anemic. So, there was more prevalence of anaemia among hemoglobinopathy than normal subjects which was statistically significant. (p=0.004).

Epidemiological and molecular study of hemoglobinopathies in Mauritanian patients.

BackgroundHemoglobinopathies, inherited disorders of hemoglobin (Hb), are the most common hereditary monogenic diseases of the red cell in the world. Few studies have been conducted on hemoglobinopathies in Mauritania. Therefore, the aim of this work is to establish the molecular and epidemiological basis of hemoglobinopathies in a cohort of Mauritanian patients and to determine the haplotype of the β‐globin gene cluster in sickle cell subjects.MethodsThe molecular screening of Hb disorders in 40 Mauritanian patients was done by a polymerase‐restriction fragment length polymorphism (RFLP) for the sickle cell disease (SCD) mutation, a PCR/sequencing method for β‐thalassemia mutations, and by the multiplex polymerase chain reaction method for the α‐thalassemia. The exploration of eight polymorphic sites (SNPs) within the β‐globin gene cluster was conducted by PCR/RFLP method, to identify the HbS haplotypes from the sickle cell subjects.ResultsThe epidemiological study of our patients showed a high incidence in the Senegal River area (52.5%) and a high ethnic prevalence for the Heratin (47.5%) and the Pular (35%). Molecular study allowed us to identify eight different mutations in our sample analyzed. They are respectively: HbS (HBB:c.20A>T) (68.75%), Cd44 ‐C (HBB:c.135delC) (8.75%), −29A>G (HBB:c.‐79A>G) (4.8%), −α‐3.7 (g.34164_37967del3804) (3.75%), IVS‐II‐849A>G (HBB:c.316‐2A>G) (2.25%) and Cd24T>A (HBB:c.75T>A), Hb Siirt (HBB:c.83C>G) and HbC (HBB:c.19G>A) each with (1.25%). Six different haplotypes are being explored among the SCD subjects with the Senegal haplotype as the most prevalent (66.7%), followed by Benin (10%), Arab‐Indians (6.7%), Bantu (3.3%), and two atypical haplotypes.ConclusionOur findings enrich the epidemiological data in our population and could contribute to the establishment of a strategy of prevention and management through screening, genetic counseling, and prenatal diagnosis of Hemoglobinopathies in the Mauritanian population.

Hemoglobinopathy screening in primary care in the Netherlands: exploring the problems and needs of patients and general practitioners

The prevalence of hemoglobinopathies in The Netherlands is increasing due to migration. Hemoglobinopathies are severe hereditary diseases. An informed reproductive choice by at-risk couples, such as pre-implantation diagnosis or termination of affected pregnancies, can be made if carriers are detected prior to conception. Using a qualitative design, the needs and wishes of patients, carriers and general practitioners were evaluated regarding carrier detection of hemoglobinopathies in primary care practice. 30 semi-structured interviews were established with 10 general practitioners, 10 patients and 10 carriers. The interviews were audio-recorded, transcribed verbatim and analysed using content analysis to identify recurring themes. Three themes were generated regarding carrier detection of hemoglobinopathies: (1) a need for more information about hemoglobinopathy, (2) a need for indications when to refer for analysis (carrier diagnostics) and (3) insight concerning organization and roles in care for hemoglobinopathy carriers and patients. These themes reflected a need to increase awareness of hemoglobinopathy, improve competences among general practitioners through better education and improvement of communication with patients and their unidentified family members. This study shows the scope of the problem and the critical need for action to improve informed reproductive decision making for the at-risk population.

USE OF HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY IN CHARACTERIZATION OF SUSPECTED HAEMOGLOBINOPATHIES IN CENTRAL INDIA-CLINICOHAEMATOLOGICAL CORRELATION

Context: Haemoglobin High Performance Liquid Chromatography is a technique for screening and initial diagnosis of haemoglobinopathies which includes group of disorders. Detailed clinical history, complete hematological prole along with newer ancillary techniques including Hb HPLC when used systematically and judiciously can achieve an early diagnosis. Family studies are of considerable importance in elucidating the nature of disorders. To aid in a cut off value for suspected haemoglobinopathies in Central India. To determine Haemoglobin prole inAims: suspected cases of Haemoglobinopathies in Central India. Hospital based retrospective and prospective study.Setting And Design: Method And Material: Blood samples in EDTA analyzed on cell counters. Red cell parameters and reticulocyte count were noted and peripheral smear evaluated. Screening tests and Serum Ferritin levels done. Samples were then run-on HPLC system. Youden's criteriaStatistical Analysis Used: was applied for calculation of cutoff values. ROC curve prepared wherever required along with calculations done on MS-EXCEL. TheResult: cutoff for beta thalassemia trait came out as HbA2&gt;= 3.35% and HbS&gt;8% for sickle cell trait amongst cases collected from Madhya Pradesh. Conclusion: Study ndings show HPLC as an excellent, powerful diagnostic tool for the direct identication of hemoglobin variants with a high degree of precision in the quantication of normal and abnormal hemoglobin fractions.