Newborn Hemoglobinopathy Research Articles

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.

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.

Challenge and difficulty of diagnosing hemoglobinopathies in newborns: about a case

The diagnosis of hemoglobinopathy is based on a range of arguments: clinic, results of a blood count, the haemoglobin study and possibly a genetic study of the globin chains. The interpretation of these profiles can be complicated, especially in newborns due to the ontogenesis of globin genes. The clinical impact can range from simple microcytosis without anemia to severe anemia requiring iterative transfusions and various clinical symptoms depending on the number and type of chains produced. Knowledge of a hemoglobin pathology remains essential because of the possible transmission and combination of these anomalies to offspring.

Electrophoretic and molecular profile of the hemoglobinopathies in newborns at a reference hospital in Mozambique

Hemoglobinopathies are monogenic diseases with a significant impact on public health. It is estimated that 5.2% of the world population has at least one genetic alteration in the genes that code for globins and in Africa, 18.2% of the population have hemoglobinopathies of clinical relevance. Using hemoglobin capillary electrophoresis, we screen newborns from the Central Maputo Hospital in Mozambique for hemoglobinopathies and then used various PCR to genotype-affected newborns. Screening of newborns revealed that 35.8% had hemoglobinopathy traits, with variants running in the position of Hb Bart (33.2%), Hb C (1.7%), Hb D (0.8%), and Hb S (sickle cell) (0.4%). The molecular test identified that 9.9% of the newborns were homozygous for 3.7 kb and/or 4.2 kb deletion genotype and that there may be an uncharacterized deletion of MCS-R located on chromosome 16. This study also confirmed the presence of hemoglobin variants, Hb Maputo and Hb S, through the identification of their defining mutations. No mutations for Hb C were found; thus, we believe that it was a result of a screening error or contamination. This study successfully identified hemoglobinopathies of clinical significance within the Mozambican population, α-thalassemia and hemoglobin S, as well as their associated genotypes. Future research should include samples from other regions of the country and the use of a more comprehensive molecular diagnostic tool. With the confirmation of clinically significant genotypes, the local health system should promote the importance of screening of hemoglobinopathies in Mozambican newborns and adults.

Synthetization, Distortion, and Geometric Correction of Isoelectric Focusing Gels for Newborn Screening

Hemoglobinopathies are inherited red blood cell disorders. They are commonly screened from newborns early after birth, and if not detected early and treated properly, some of them can be fatal. One of the most common method for screening hemoglobinopathies in newborns is isoelectric focusing (IEF). IEF separates different hemoglobins to distinct bands based on their isoelectric point. Different hemoglobinopathies can be detected from IEF as additional bands from normal hemoglobins and also from quantitative issues in normal hemoglobins. However, distortions are commonly present in IEF gels that hinder the interpretation of the gel. In this study, we showcase a method for straightening distorted images of IEF gels. Since no dataset containing images of IEF gels was present, we created a novel Sig2Img synthetic sample generator. This allowed us to create gel sides with any desired bands and intensities. Artificial distortions were also applied with basic image processing functions, to represent different kinds of distortions commonly found in IEF gels. Fifteen experiments were created to evaluate the method. The experiments showed that the correction method managed to straighten gel sides even with added difficulties, such as within-sample and sample-to-sample distortions, and added Gaussian noise. Experiments also showed that the method retained the relative quantities of the bands accurately. The straightening enables easier visual interpretation of the gel when screening for hemoglobinopathies. It also allows accurate quantitation of bands which was not originally possible from distorted samples. This gives the method clinical significance, as quantitation can be added to the clinical workflow.

Incidence of Sickle Cell Disease and Other Hemoglobinopathies in Burkina Faso: Results of a Five-Year Systematic Neonatal Screening (2015-2019) in Four Urban Hospitals

Hemoglobinopathies, mainly Sickle cell disease (SCD), are the most common monogenic disorders in Africa. In Burkina Faso, data on these diseases are scarce, mainly hospital-based in Ouagadougou and its surroundings. In order to assess the incidence and allelic frequencies of the main hemoglobinopathies in newborns in Burkina Faso, we conducted a cross-sectional study from 2015 to 2019 in four hospitals. The study included babies of both sexes, regardless of ethnic group and parents’ hemoglobin status. It was a newborn screening and hemoglobin variants were detected using isoelectric focusing on cord blood samples and confirmed using hemoglobin electrophoresis by high-performance liquid chromatography. The proportions and cumulative incidences of the different hemoglobinopathies were computed. Hardy-Weinberg equilibrium law was applied to calculate genotypic and allelic frequencies. The significant level was p ere from Bobo-Dioulasso. Abnormal hemoglobin was found in 27.1%, representing a cumulative incidence of 1:4 newborns. The incidence of SCD was 1.9% (1:53 newborns) with 27.9% of homozygous SS. Homozygous CC and compound heterozygous Cβ-Thalassemia accounted for 1.1%. SCD cases were 1.51 times higher in Bobo-Dioulasso (OR = 1.51; 95% CI [1.09 - 2.10]: p = 0.013). The observed genotype frequencies were significantly different from the expected ones (p 0.001). The βS and βC alleles represented 5.1 and 9.9%, respectively. This study showed a high incidence of hemoglobinopathies. Such results raise the question of control strategies for these hemoglobinopathies in our country.

Southeast Asian Ovalocytosis and Hemoglobinopathies in Newborns: Prevalence, Molecular, and Hematologic Analyses.

Southeast Asian ovalocytosis (SAO) is an inherited red blood cell (RBC) membrane disorder, whereas hemoglobinopathies are inherited globin gene disorders. In an area where both diseases are prevalent, the interaction between them resulting in variable hematologic parameters can be encountered. However, little is known about the genetic interaction of SAO and thalassemia. We investigated the prevalence of SAO and hemoglobinopathy genotypes among newborns in southern Thailand. This study was carried out on 297 newborns recruited consecutively at Naradhiwas Rajanagarindra Hospital in the south of Thailand. The SAO was identified on blood smear examination and polymerase chain reaction analysis. Thalassemia genotypes were defined. Hematologic parameters and hemoglobin (Hb) profiles were recorded and analyzed. Among 297 newborns, 15 (5.1%) carried SAO, whereas 70 (23.6%) had thalassemia with 15 different thalassemia genotypes. Abnormal Hb including Hb C, Hb Q-Thailand, and Hb D-Punjab were observed in 5 newborns. It was found in the nonthalassemic newborns that RBC count, Hb, and hematocrit of the nonthalassemic newborns with SAO were significantly lower than those without SAO. The same finding was also observed in the thalassemic newborns; RBC count, Hb, and hematocrit of the thalassemic newborns with SAO were significantly lower than those without SAO. However, the mean corpuscular volume, mean corpuscular Hb, and RBC distribution width of the SAO-newborns were significantly higher. Both SAO and hemoglobinopathy genotypes are common in southern Thailand. One should take this into consideration when evaluating neonatal anemia and other hematologic abnormalities. Identification of both genetic defects and long-term monitoring on the clinical outcome of this genetic interaction should be essential to understand the pathogenesis of these common genetic disorders in the region.

Clinical Utility of Confirmatory Genetic Testing to Differentiate Sickle Cell Trait from Sickle-β+-Thalassemia by Newborn Screening.

Hemoglobin separation techniques are the most commonly used laboratory methods in newborn screening and confirmatory testing programs for hemoglobinopathies. However, such protein-based testing cannot accurately detect several hemoglobinopathies in newborns, especially when β-thalassemia mutations are involved. Here, we describe a consecutive cohort of newborns who were identified by newborn screening to have a likely diagnosis of sickle-β+-thalassemia (having an “FSA” pattern) who were determined to have sickle cell traits by confirmatory and genetic testing. We illustrate the clinical utility of genetic testing to make a correct and timely diagnosis in the setting of newborn screening for hemoglobinopathies.

Predictors of Hydroxyurea Use in Children with Sickle Cell Disease

Background: Since hydroxyurea emerged as an effective therapy for sickle cell disease (SCD), there have been numerous studies that have demonstrated its safety and efficacy in children and adults with SCD. In their 2014 guidelines, the NHLBI recommended that hydroxyurea treatment should be offered to all infants and children with sickle cell anemia (HbSS and HbS/beta0 thalassemia) starting at 9 months of age. However, hydroxyurea is underused among children and adolescents with SCD and to date, there have been no studies that have identified the specific determinants that may predict hydroxyurea adherence in these patients.Objectives: 1. To identify predictors of hydroxyurea adherence in children with SCD. 2. To measure the rate of hydroxyurea use among CHEO patients with SCD who were born between January 1, 2003 and December 31, 2015; and 3. To compare the rates of SCD-related complications between patients who were not prescribed hydroxyurea, patients who were adherent to hydroxyurea and patients who were not adherent to hydroxyureaMethods: We extracted medical chart data to identify patients with SCD who were born between January 1, 2003 and December 31, 2015. Patients were classified as either “Not prescribed hydroxyurea” or “Prescribed hydroxyurea” based on clinical documentation and the presence of at least one hydroxyurea outpatient prescription. For those patients who were prescribed hydroxyurea, hematological indices were collected and analyzed over time to estimate adherence to hydroxyurea. To measure the adherence of children prescribed hydroxyurea, we examined the trends in the patient's hematological indices after their first prescription of hydroxyurea. Adherence was defined as increased hematological indices (from baseline) by greater than or equal to any 2 of the following: Mean corpuscular volume (MCV) by 10 fL; Hemoglobin levels (g/L) by 10 g/L and/or %HbF (fetal hemoglobin) by 10%. We measured the frequency of disease-related complications among CHEO patients with SCD according to their use of hydroxyurea and used multivariate analyses to evaluate immigration status, newborn screening status, SCD subtype, SCD complications, income, age and sex as predictors for hydroxyurea adherence.Results: Children with HbSS were more likely to have been prescribed hydroxyurea compared to children with HbSC (87.8% vs. 9.5%). Canadian citizenship, newborn hemoglobinopathy screening and lower familial income were associated with better hydroxyurea adherence (Table 1). Although the association was not statistically significant, patients were more likely to be prescribed hydroxyurea if they were from a lower income background (61.9% for lowest and second lowest quartiles vs. 38.1% for third and highest quintiles). Patients were also more likely to adhere to hydroxyurea if they did not have private medical insurance for hydroxyurea coverage (Table 1). Finally, hydroxyurea adherence was associated with reduced rates of health care utilization and SCD-related complications (Table 2).Conclusions: In line with previous studies of hydroxyurea for the treatment of SCD, patients who were adherent to hydroxyurea had fewer complications compared to those patients who were either non-adherent to or not prescribed hydroxyurea. Similarly, patients had fewer complications after being prescribed hydroxyurea compared to before they started hydroxyurea with a reduction in the rate of ED visits, acute chest syndromes, complications, transfusions and hospitalizations. Patients from non-immigrant families, patients who were identified through newborn hemoglobinopathy screening and patients from lower income families were more likely to be adherent to hydroxyurea. Although the results of this study were limited by its small sample size, further studies will clarify these determinants of hydroxyurea adherence among SCD patients and enable clinicians to improve hydroxyurea adherence for SCD patients. DisclosuresKlaassen:Shire: Consultancy; Novartis: Research Funding; Hoffman-La Roche: Consultancy; Amgen Inc.: Membership on an entity's Board of Directors or advisory committees; Octapharma AG: Consultancy, Honoraria; Agios Pharmaceuticals Inc.: Consultancy; Cangene: Research Funding.

Hemoglobinopathies in newborns in the southern region of the Triângulo Mineiro, Brazil. Cross-sectional study.

Hemoglobinopathies are among the commonest and most widespread genetic disorders worldwide. Their prevalence varies according to ethnic composition and/or geographical region. The aim of this study was to investigate the presence of hemoglobinopathies and their association with ethnicity among 1,004 newborns, to confirm the guideline of the Brazilian National Neonatal Screening Program. Cross-sectional study conducted in a public referral hospital in the Triângulo Mineiro region, Minas Gerais, Brazil. Qualitative assessment of hemoglobin was performed through electrophoresis on cellulose acetate: at alkaline pH to identify the hemoglobin (Hb) profile and at acid pH to differentiate Hb S from Hb D and Hb C from Hb E and others that migrate to similar positions at alkaline pH. Neutral pH was used to detect Hb Bart's identified in alpha thalassemia (α-thal). The elution method after electrophoresis was used to quantitatively assess hemoglobins. There was predominance of α-thal, with 105 cases (10.46%), followed by Hb S with 61 cases (6.08%, comprising 46 Hb AS, 2 Hb SS and 13 Hb S/α-thal), 9 cases (0.9%) of Hb AC and 6 cases (0.6%) suggestive of beta thalassemia (β-thal). The frequency of hemoglobinopathies was significantly higher among Afro-descendants. These findings corroborated of the National Neonatal Screening Program for diagnosing sickle cell disease and Hb C, Hb D, Hb E and β-thal hemoglobinopathies.

Noninvasive Buccal Swab Antigen Sample and Molecular Testing Provides Extended Antigen Typing for Patients with Hemoglobinopathies

To demonstrate the feasibility of performing a noninvasive, molecular-based red blood cell (RBC) antigen test on infants and very young children with sickle cell disease as part of a statewide newborn screening follow-up program. A prospective pilot project was conducted using a noninvasive buccal swab and test kit to perform DNA-based, extended RBC phenotyping in 92 children participating in a newborn hemoglobinopathy screening follow-up program. Reported data include the extended panel of antigens detected by molecular analysis compared with unaffected population estimates. Molecular-based RBC antigen testing was successful, with extended RBC typing generated for all subjects. Molecular testing detected several rare negative or rare positive phenotypes, demonstrating the utility of obtaining an extended antigen panel. This study demonstrates the feasibility of performing antigen testing on buccal swab specimens from children with sickle cell disease as part of a newborn screening follow-up program with the aim of allowing specific unit matching to prevent alloimmunization with RBC transfusions. The general applicability of testing may be limited by a lack of uniform insurance coverage for buccal swab testing, however.

Neonatal screening for sickle cell disease and other hemoglobinopathies in "the changing Europe".

Inherited hemoglobin disorders (sickle-cell disorders and thalassaemias) represent an increasing global health problem. The early detection of sickle cell disease allows counselling for family members about disease management and future reproductive decisions. The aim of the present study was to estimate the birth prevalence of hemoglobinopathies in newborns of Italian couples and couples of immigrants from endemic areas living in an urban area of northern Italy in order to assess the opportunity of implementing a neonatal screening programme for hemoglobin disorders. Inclusion criteria were infants with at least one of the parents from high risk areas of hemoglobinopathies (Po delta and Sardinia, Italy; Mediterranean area; sub-Saharan Africa; Brazil; Asia) or a positive family history for hemoglobinopathies. The number of infants included in the present study was 337: 13.8% out of 2447 children born at Azienda Ospedaliera Universitaria (AOU) "Maggiore della Carità", Novara, Italy, from 31 December 2012 to 31 January 2014 and 47.6% of 710 infants with at least one foreign parent. 232 infants were wild-type (68.8%) for hemoglobin variants; 48 subjects (14.2%) had no hemoglobin variants, but we could not exclude the presence of a thalassemia trait (Hb A < 15%): a further monitoring of hemoglobin electrophoresis at 6 months was therefore recommended. 20 infants (5.9%) had Hb S (7.7% ± 3 of the total hemoglobin; range 3.5 - 13) and were diagnosed as Hb S carriers and 2 infants (0.6%) had Hb C (7.8% and 12.1% of the total hemoglobin, respectively) and were diagnosed as Hb C carriers. Based on our results, we can conclude that: (i) the sickle-cell disorder (Hb S) is relatively high in our territory, with a heterozygous frequency in infants at risk of 5.9%; (ii) the neonatal screening for hemoglobin disorders appears to be a valid, easy to perform test, which allows an early diagnosis and timely payment of hemoglobinopathies in populations at risk.

Newborn screening program for hemoglobinopathies in Rio de Janeiro, Brazil

Newborn screening for hemoglobinopathy in Brazil has been decentralized until 2001 when the Health Ministry of Brazil established the National Newborn Hemoglobinopathy Screening Program. The State of Rio de Janeiro started a program in collaboration with the State Health Department and the Institute of Hematology in Rio (HEMORIO). The goal of this study was to evaluate the effectiveness of the first 10 years of the Newborn Hemoglobinopathy Screening Program in identifying and managing infants with Sickle cell disease (SCD) in the State of Rio de Janeiro. Blood samples from 1,217,833 neonates were analyzed by High Performance Liquid Chromatography. Infants with SCD were enrolled in comprehensive treatment programs. Data showed that 4.87% of the newborns were heterozygous for a hemoglobin variant, 0.08% were homozygous or doubly heterozygous for abnormal hemoglobins and 95.02% had normal hemoglobin. All the 912 newborns with SCD were referred for treatment at HEMORIO, 34 (3.7%) of these died due to acute chest syndrome, sepsis or splenic sequestration. Four more children died of unknown causes. The implementation of the Rio de Janeiro Newborn Screening Program gradually increased the area of the State covered by the program. Data collected during the 10 years of the program showed reduction in mortality of patients with SCD in comparison to available historical statistical data before the implementation of the national screening program. This 10-year study showed that early diagnosis and treatment of newborns was associated with improved survival and quality of life of Brazilian children with SCD.

Pilot study of hemoglobinopathies in newborns of the Rafael Calvo maternity clinic of Cartagena, Colombia

The hemoglobinopathies are a heterogeneous group of congenital anemias from Africa, Asia and the Mediterranean. Due to the migration of this population have spread worldwide, especially in Latin America and the Caribbean region, which Cartagena de Indias is included, with a large proportion of people of African descent. The lack of routine programs that include an appropriate methodology for precise identification of those affected and carriers, impossible to know the real behavior of this disease in our country and an early and appropriate to the patients before the disease manifests itself and produce its serious consequences. To estimate the incidence and describe the epidemiological profile of hemoglobinopathies in newborns Rafael Calvo Maternity Clinic of Cartagena, in the period from January to June 2010. Prospective descriptive study of a population of 1,729 newborns. Samples were collected cord blood on filter paper. Isoelectric focusing electrophoresis (IEF )was used to separate the haemoglobins. 94.4% (1,633 samples) were normal (hemoglobin FA), 4.5% (78 samples) were heterozygous for haemoglobin S (HbFAS), 1% (17samples) were heterozygous for haemoglobin C (hemoglobin FAC) and 0.1% (1 sample) was double heterozygous SC (hemoglobin FSC). Due to the high incidence of hemoglobinopathies found in this pilot study highlights the importance and necessity of establishing an obligatory neonatal screening in the city of Cartagena, in order to make a timely diagnosis and monitoring of affected and carrier.

Incomplete Follow-up of Hemoglobinopathy Carriers Identified by Newborn Screening Despite Reporting in Electronic Medical Records

ObjectiveHas the recent availability of newborn hemoglobinopathy screening results within patient electronic medical records (EMR) of birth hospitals facilitated follow-up by primary care pediatric providers? MethodsAn online survey of all 137 primary care pediatric providers at a New York City academic medical center was conducted in 2008-2009 to assess practices for hemoglobinopathy trait follow-up. Physicians were resurveyed 1 year later, following educational outreach and a letter of instruction underscoring the availability of screening results in the EMR. All 62 primary care pediatricians were surveyed at a nearby city hospital for comparison. ResultsOverall response rate for the initial survey at the teaching hospital was 58% for pediatricians (N = 57) and family physicians (N = 23), and 50% for pediatricians at the city hospital (N = 31). Despite high prevalence of hemoglobinopathies in the population served and screening results in EMRs, only 46.2% of providers surveyed at the academic center reported routinely checking results of their infant patients: 38.6% of pediatricians and 66.7% of family practitioners. Some respondents were unaware that results are available in the EMR. The proportion of providers checking screening results was not significantly affected by educational intervention (N = 40). Provision of recommended follow-up for a positive trait result was modestly improved, especially in referring families for genetic counseling (25% to 50%, p < .01). In contrast, most pediatricians (83%) at the city hospital routinely check and perform follow-up. ConclusionDespite access to results in the EMR and targeted educational outreach, follow-up of hemoglobinopathy screening by primary care varies widely across clinical sites.

Prenatal screening of thalassemia in 7210 samples of neonatal cord blood and G6PD deficiency

Objective To explore the incidence of newborn hemoglobinopathy and erythrocyte enzyme disorders after regular prenatal visits and genetic consulting. Methods The band on hemoglobin electrophoresis and the G6PD level were detected in 7210 samples of umbilical cord blood by hemoglobin electrophoresis and G6PD ratio method. Results Of 7210 samples,the detection rate of G6PD deficiency was 4.38％. The detected rates of α -thalassemia with a/a mutation and standard α-thalassemia were 2.50％and 5.89％. The incidence of the three disorders in 2009 was decreased by 0.18％,0.08％,and 0.44％,as compared with 2008. Conclusions The probability of the incidence of the disorders reduces in the confirmed low-risk neonates after regular prenatal visits and consulting,as compared with the predictive probability. Prenatal visits and genetic consulting play an important role in preventing the birth rate of neonates with severe thalassemia. Key words: Hemoglobin electrophoresis; Glucose-6-phosphate dehydrogenase; Umbilical cord blood; Prenatal visits; Genetic consulting

Newborn screening for hemoglobinopathies using capillary electrophoresis technology: Testing the Capillarys® Neonat Fast Hb device

Objectives To diagnose hemoglobinopathies in newborns by separating and measuring the Hb fractions on high throughput capillary electrophoresis. To test and validate the Capillarys Neonat Fast Hb device (Sebia) on fresh and dry blood samples. Design and methods The Hb fractions in 1.600 cord blood samples from the multi ethnic Dutch population were separated and measured. Further, the sensitivity, specificity and reproducibility of the device in detecting abnormalities and measuring the Hb fractions were estimated. Results The apparatus separated all significant Hb fractions that should be detected during newborn screening (NBS) with 100% sensitivity. The reproducibility of the migrations guaranteed putative specificity for the few relevant frequent variants observed (HbS, C, and E). The estimation of the HbA and F fractions proved reliable using a well-designed integration mode. Discussion Due to the limited number of samples no cases with sickle cell disease or β-thalassemia major were found in this cohort. However, the heterozygous state for the common variants associated with these diseases was clearly recognizable. The measurements were sufficiently precise to recognize sickle cell disease, β-thalassemia major and intermedia and to identify carriers including possible β-thalassemia. Therefore, Capillarys Neonat Fast Hb (Sebia) can be considered as a valid instrument for NBS of the Hemoglobinopathies on fresh and dry blood samples.

Newborn Sickle Cell Screening in a Region of Western New York State

To assess local trends in the incidence of sickle cell disease (SCD) and hemoglobin (Hb) S trait. Hemoglobinopathy clinic follow-up and cohort mortality rates were also evaluated. A longstanding newborn hemoglobinopathy screening program was reviewed. Incidence rates were computed with information from a confidential database, specialty clinic/hospital data, and local birth statistics. Over 27 years, the incidence of Hb SS in live black births was 0.163% or 1 in 615. Over 18 years, the incidence of Hb AS was 8.5% or 1 in 11.8. No significant differences in the incidence of Hb SS, Hb AS, and the S allele were found over time. Specialty clinic follow-up improved. Death before age 18 years was documented for 6 SCD cases (2.8%; mortality rate of 0.23 per 100 patient years). Local screening activities may have had an impact on participation in specialized SCD care and the disease-associated mortality rate. The incidence of Hb SS has remained unchanged over 27 years, and that of Hb S trait and the S allele has been unaffected in the last 18 years. Trait notification goals and approaches should be reevaluated.

Hemoglobinopathies in newborns from Salvador, Bahia, Northeast Brazil

Hemoglobinopathies are hereditary disorders of the hemoglobin molecule with a high prevalence worldwide. Brazil has a prevalence of 0.1 to 0.3% of newborns with sickle cell anemia and 20.0 to 25.0% of heterozygous alpha2 thalassemia among African Brazilians. In the present study, we investigated the presence of variant hemoglobins and alpha2(3.7 Kb) and alpha2 (4.2 Kb) thalassemia in newborns from Salvador, Bahia, Brazil. Samples of umbilical cord blood from a total of 590 newborns were analyzed, of which 57 (9.8%) were FAS; 36 (6.5%) FAC; one (0.2%) SF; and five (0.9%) FSC. One hundred fourteen (22.2%) newborns had alpha2(3.7 Kb) thalassemia, of whom 101 (19.7%) were heterozygous and 13 (2.5%) homozygous, showing statistical significance for hematological data between newborns with normal alpha genes and alpha2(3.7 Kb) thalassemia carriers. The alpha2(4.2 Kb) thalassemia was not found. Frequencies found in the present study confirm that hemoglobinopathies are a public health problem in Brazil, emphasizing the need for neonatal screening and genetic counseling programs.

An Effective Program to Resolve Ambiguous Results from State Newborn Hemoglobinopathy Screening.

Newborn screening (NBS) for hemoglobinopathies is an important mechanism for identification of affected individuals so that prophylactic treatment and comprehensive care are delivered before life-threatening complications occur. Whilst more common Hb variants, such as Hb S and Hb C, are readily identified, many children with other potentially significant Hb variants never have a conclusive diagnosis made by state newborn screening programs. In conjunction with the National Newborn Screening and Genetics Resource Center (NNSGRC), we investigated whether unconfirmed or ambiguous samples could be rapidly diagnosed and reported, using only a portion of the original dried blood spot (DBS) specimen.State NBS programs were approached about sending DBS samples from newborns with ambiguous Hb results for further testing. Using a single 6 mm hole punch from the original DBS, the primary screening results were first confirmed with HPLC, IEF and citrate agar electrophoresis. With the same sample, genotyping for Hb S, C, E, Knossos, D-LA, and O-Arab, and > 95% of the most common β-thalassemia mutations, was performed using a novel linear array platform. Samples revealing Bart's Hb were tested for common deletional and non-deletional α-thalassemia mutations using gap-PCR or DNA sequencing. The test results, along with a clinical interpretation, were reported back to the NBS programs within 2 weeks.During a one-year period (08/03–08/04), a total of 309 newborn samples from 30 participating states were received for definitive diagnostic testing. Of these, 115 (37%) revealed a clinically significant genotype. Specifically, 102 newborns had sickle cell disease (55 HbSS, 27 HbSC, 16 HbS/β-thal, 3 HbSE, 1 HbS/O-Arab); 6 newborns had β-thalassemia (2 β0-thal, 4 E/β-thal); and 7 had α-thalassemia (5 HbH, 1 HbH-CS, 2 α-triplication). Compound heterozygosity for 2 Hb variants was found in 15 cases and interpreted as clinically insignificant. Another 14 samples revealed a clinically benign HbEE genotype. A Hb variant trait was identified in 124 samples and 41 samples had a normal Hb genotype.This NNSGRC-sponsored pilot study demonstrates that a centralized referral laboratory providing definitive diagnostic testing for hemoglobinopathies is not only feasible, but a much needed resource for many state newborn screening programs. Using rapid and efficient molecular methods, our laboratory identified a clinically significant sickling of thalassemic disorder in 37% of previously unconfirmed newborn samples. Based on these results, the implementation of a referral laboratory to provide prompt definitive diagnosis of clinically relevant hemoglobin variants would be an invaluable extension of existing newborn screening programs.