Screening For Hemoglobinopathies Research Articles

Neonatal haemoglobinopathy screening: review of a 10-year programme in Brussels

Since 1994, a neonatal screening programme for major haemoglobinopathies has been conducted in Brussels. We performed a 10-year re-evaluation of the incidence of haemoglobinopathies in Brussels and found that of the 118,366 newborns screened, 64 were diagnosed with a sickle cell syndrome, six had beta-thalassaemia major, four had a haemoglobin C disease and three had a haemoglobin H disease. Of the 64 babies with a sickle cell disease, two died before the age of two years and two did not present at the first neonatal visit. Of the six babies suffering from beta-thalassaemia major, all are alive and two have undergone a haematopoietic stem cell transplantation. The universal neonatal screening programme for haemoglobinopathies should be maintained in Brussels.

Prevalencia de hemoglobinopatías en mujeres gestantes en el área sanitaria de Lanzarote

The aim of this study is to analyze the global prevalence of carriers of heterozygous hemoglobinopathies among pregnant women settled in Lanzarote.A epidemiologic cross-sectional observational investigation was undertaken to study the prevalence of hemoglobinopathies in 2,436 pregnant women in Lanzarote. The techniques of primary screening were hemoglobin electrophoresis on cellulose acetate at alkaline pH for the detection of hemoglobin variants, and the quantification of HbA2 and HbF for the diagnosis of b thalassemia trait. The study to confirm the diagnosis of structural hemoglobinopathies was based on hemoglobin electrophoresis on citrate agar at acid pH, isolectric focusing and high-performance liquid chromatography (HPLC). The molecular characterization of b thalassemia trait (HbA2 >3.5%) was carried out by techniques using a real time PCR procedure with specific fluorescently labelled hybridization probes and allele-specific amplification (PCR-ARMS).The global prevalence of hemoglobinopathies was 11.90 corresponding to 9.44 for structural hemoglobinopathies and 2.46 for heterozygous b thalassemias. A variant hemoglobin was detected on 23 women and the distribution was as follows: thirteen carriers of hemoglobin S, seven HbC trait, two HbD trait and one "unstable" hemoglobin. 82.6% of the variant hemoglobins found were from migrant population from Africa and America.The high prevalence of carriers of structural hemoglobinopathies in Lanzarote justifies the initiation of programs for screening for hemoglobinopathies to prevent the emergence of severe states causing disease.

Cribado de hemoglobinopatías en una cohorte de recién nacidos en la Comunidad de Madrid

Congenital structural hemoglobinopathies are a group of disorders whose incidence has experienced an increase in recent years, due to the higher number of immigrants living in the Region of Madrid. Given the possibility of starting early prophylactic measures, it seems advisable to carry out an screening of hemoglobinopathies in this region. The objective of this work was to know the current incidence of hemoglobinopathies in the Hospital Clinico San Carlos and to analyze the more suitable laboratory diagnostic tests. An ambispective cohort study, with 3,365 newborns studied at the Hospital Clinico San Carlos from May 2003 to June 2004. All were studied by cation exchange HPLC [Variant (Bio-Rad)] and pathologic specimens were analyzed by reversed phase HPLC. Hemoglobinophaty was detected in 26 children with the HPLC Variant, with a global incidence of 7.7 per 1,000 newborns: 1 case of sickle cell disease, 18 cases of sickle cell trait, 1 HbC, 1 HbE/A2 and five indeterminate cases. Neonatal screening for hemoglobinopathies in the Region of Madrid is necessary, and the HPLC Variant is an appropriate technique.

Cribado neonatal de hemoglobinopatías y déficit de glucosa-6-fosfato deshidrogenasa en Cataluña. Estudio piloto en población anónima no relacionada

This was a preliminary study on the prevalence of the HbS gene, associated with sickle cell disease, other hemoglobinopathies and G6PD deficiency of immigrant and non-immigrant population of Catalonia. A total of 3,189 blood samples from the Catalan Neonatal Screening Program for Metabolic Diseases (CNSPMD) including 1,620 from immigrant population were screened for haemoglobinopathies and G6PD deficiency. For screening of hemoglobinopathies the high performance liquid chromatography (HPLC) method was used and for the screening of G6PD deficiency, we used the fluorescent spot test as described by ICSH. 1. Hemoglobinopathies: in 47 samples from immigrant population 2 cases of sickle cell anemia (phenotypes FS and FSC) were detected as well as 45 cases of heterozygote carriers of different pathological hemoglobins (HbS, HbC, HbD and HbE). 2. G6PD deficiency: in 29 samples, 3 cases of G6PD deficiency belonging to local (non-immigrant) population of G6PD were detected. The incidence of sickle cell disease in the risk population of Catalonia is 1 case out of 810 samples. This value is significantly higher than that reported for any of the metabolic diseases included in the CNSPMD. Despite it is a preliminary study, the results obtained give further support to the convenience of incorporating a neonatal screening of hemoglobinopathies, at least in the risk population, to the official programs of newborn screening. Due to its feasibility and low cost, a similar criterion might be adopted for the neonatal screening of G6PD deficiency.

Three New α-Thalassemia Point Mutations Ascertained Through Newborn Screening

We report three new α-thalassemia (thal) point mutations detected during newborn screening for hemoglobinopathies. The first mutation is a single nucleotide deletion (−A) that abolishes the translation initiation codon of the α2-globin gene, detected in a newborn of Hmong ethnicity who carried the Southeast Asian α0-thal deletion (αTα/– –SEA). The second mutation, a frameshift caused by a single nucleotide deletion in exon 2 of the α1-globin gene [codon 78 (−C)], was detected in a Black/Chinese newborn who also carried the Southeast Asian α0-thal deletion (ααT/– –SEA). The third mutation was a frameshift in exon 3 of the α2-globin gene, codons 113/114 (−C). This mutation was detected in a newborn who carried the 3.7 kb α+-thal deletion (αTα/–α3.7).

Neonatal Cyanosis Due to a Novel Fetal M-Hemoglobin: Hemoglobin F-M Circleville (Gγ63 His→Leu).

Neonatal cyanosis can result from a multitude of acquired and inherited causes. Cyanosis resulting from fetal M-Hemoglobin variants is a rare cause of this condition. In fact, to date, only two Gγ variants causing methemoglobinemia and cyanosis in the newborn have been reported. These are Hb F-M Osaka (Gγ63 His→Tyr) and Hb F-M Fort Ripley (Gγ92 His→Tyr). We report a novel fetal M-hemoglobin presenting with neonatal cyanosis. The propositus was a 1-day old Caucasian male admitted to the hospital because of cyanotic episodes. The patient had an O2 saturation of 85% on room air and required supplemental O2 during his 10-day hospitalization. The family history was significant for a 4-year old sister having a 5-day hospitalization after delivery for cyanosis. The sister required supplemental O2 for 4–5 months to maintain a satisfactory O2 saturation. Both parents were healthy and had no recollection of neonatal cyanosis or O2 requirement. The newborn screening for hemoglobinopathies reportedly showed Hb F, A, and a variant migrating between Hb S and Hb F. Cation exchange HPLC performed at 1-month of age revealed 68.4% Hb F; 17.5% Hb A, and 14.0% Hb X, eluting between Hb F and Hb A. Reverse phase HPLC showed only βA, αa, Gγ, and Aγ chains without any detectable abnormal chains. O2 affinity showed a P50 of 24.2mmHg (control 23.4mmHg). Sequencing of the PCR amplified Gγ gene revealed heterozygosity for a CAT→CTT mutation (His→Leu) at codon 63. (GenBank Acession # AY662983). This novel variant was named Hb F-Circleville [GγE7(63)His→Leu]. The M-hemoglobins arise from mutations in the conserved proximal (F8) or distal (E7) histidine residues, which are important heme contacts. Substitution of these residues lead to methemoglobinemia and cyanosis. Fetal Hb variants causing methemoglobinemia are rare causes of neonatal cyanosis. Hb F-Circleville is only the third fetal M-Hb reported to date. The prognosis of cyanosis is excellent in these cases, as Hb F declines post natally and is replaced by normal Hb A. Supplemental O2 may be required for several months during the postnatal period as was the case with this patient. Some fetal M-Hbs have been shown to arise as de novo mutations. In our case, an older sister and the mother were both proven to carry the Gγ63 His→Leu mutation consistent with autosomal dominant inheritance.

Prevalence of Frequent α-Globin Gene Deletions in Neonates with HbH in Cord Blood.

Introduction: Increasing multiethnicity is likely to make α-thalassemia minor more prevalent in Western metropolitan areas. It also increases the probability of finding newborns with Hemoglobin H disease or hydrops foetalis. Therefore, there is a need to implement screening methods to detect α-thalassemia at birth. Screening should also identify patients and families with specific requirements in genetic counselling. The goal of the present study is to evaluate the value of HbH measurement in cord blood to identify patients with α-globin deletions and patients with genotypes at risk that should be directed towards genetic counselling.Methods: A universal neonatal screening for hemoglobinopathies and thalassemia has been performed at our institution since 2002. Between October 2002 and July 2005, hemoglobin HPLC (High Performance Liquid Chromatography, Bio-Rad Variant II)) analysis performed on ombilical cord blood identified 123 newborns with hemoglobin H (HbH). Subsequently, DNA samples were analysed by m-PCR to detect the most common alpha-globin gene deletions:-α 3.7, -α 4.2, -α 20.5, -- SEA,-- FIL, -- THAI, -- MED. Groups were formed based on the genotype (1 deletion, 2 deletions, 2 deletions in cis, 2 deletions in trans) The mean level of HbH was calculated for each genotype and group. Student t-test was used to compare the level of HbH between the different groups. Due to the heterogeneity of the group populations, a Mann-Whitney test was also used to corroborate results obtained with t-test.Results: At least one α-globin gene deletion was observed in 90.2% of cases.(95%I.C: 83.5%-95.0%). Comparison between the groups based on the number of α-globin gene deletion and their allelic distribution allowed identification of significant differences in the HbH levels. Results were similar with Mann-Whitney (data not shown).Comparisons are presented in Table 1. HbH levels for the specific genotypes are presented in Figure 1.Conclusion: Hemoglobin HPLC analysis performed on umbilical cord blood allows rapid and efficient detection of HbH and highly predicts the presence of common α-globin gene deletions. Moreover a significant correlation is demonstrated between the levels of HbH and the presence of an α-thalassemic genotype. HbH level seems to correlate positively with the clinical severity of the genotype. However, a discriminate level of HbH could not be established to identify patients specifically requiring genotyping and genetic counselling. Further testing is necessary to evaluate the causes of HbH expression when there is no α-globin gene deletion. [Display omitted] Mean HbH level (% of total hemoglobin)deletions/allelic distributionHbH level (means)HbH level (range)level of significance1 deletion2.101.4–5.92 deletions6.964.0–12.6p<0.0011 deletion2.101.4–5.92 deletions trans6.504.0–9.2p<0.0011 deletion2.101.4–5.92 deletions cis10.67.3–12.6p<0.012 deletions trans6.504.0–9.22 deletions cis10.67.3–12.6p<0.001

Proteomic Detection of Beta Thalassaemia Trait Using Electrospray Mass Spectrometry-Mass Spectrometry.

Introduction Mass spectrometry has proved a valuable tool in the unequivocal characterisation of haemoglobin variants detected during routine haemoglobinopathy screening using High Performance Liquid Chromatography (HPLC) and/or isoelectric focusing. We have recently described a rapid and specific electrospray mass spectrometry-mass spectrometry (MSMS) method, using proteomic mutation targeting, for simultaneous detection of the clinically significant haemoglobinopathies; haemoglobin (Hb)S, HbC, HbE, HbDPunjab and HbOArab. Here we report additional transitions within the 1min cycle time, using delta chains as a surrogate HbA2, with the objective of detecting beta thalassaemia trait.Method Blood samples are digested using trypsin, which results in specific cleavage of globin chains at peptide bonds adjacent to lysine and arginine residues, to produce a series of well-characterised peptides. There is strong amino acid sequence homology between the beta and delta chains of haemoglobin, however tryptic digestion produces series of 15 (T1–T15) and 16 (T1–T16) peptides, for beta and delta chains respectively, with differences in T2, T3, T5, T10, T12, T13 and T14. In this report we have investigated the diagnostic utility of T2: beta sequence SAVTALWGK, average mass 932.1 daltons, delta sequence TAVNALWGK, average mass 959.1 daltons. In multiple reaction monitoring mode the respective T2 [M+2H]2+ ions, m/z 466.8 and 480.3, are selected, fragmented, and the singly charged ions of the informative peptide fragments, VTALWGK and VNALWGK, detected.Results The percentage area ratio of delta/(beta+delta) was calculated and compared with the classical percentage HbA2 value obtained by HPLC. 66 samples with HbA2 values within our normal range (mean 2.7%, range 1.8–3.4), and 58 with HbA2 values indicative of beta thalassaemia trait (5.2%, 4.2–7.9) were analysed by MSMS and the corresponding delta/(beta+delta) ratios were 1.7%, 0.9–2.3 and 3.4%, 2.5–6.0. In addition, in 2 further HbS beta thalassaemia zero compound heterozygote samples confirmed by beta gene sequencing the ratios were 4.1% and 3.7%.Conclusion This relatively small study provides evidence that beta thalassaemia trait may be diagnosed by MSMS and represents another step towards comprehensive MSMS population screening for clinically significant haemoglobinopathies.

ACOG Practice Bulletin #64: Hemoglobinpathies in Pregnancy

The hemoglobinopathies are a heterogeneous group of single-gene disorders that include the structural hemoglobin variants and the thalassemias. More than 270 million people worldwide are heterozygous carriers of hereditary disorders of hemoglobin, and at least 300,000 affected homozygotes or compound heterozygotes are born each year (1). The purpose of this document is to review the most common hemoglobinopathies and to provide recommendations for the screening and clinical management of hemoglobinopathies during pregnancy.

Triagem neonatal como um problema de saúde pública

Estudos realizados na população brasileira revelam que, no Brasil, existem aproximadamente 10 milhões de indivíduos heterozigotos para os genes da Hb S, da Hb C e da talassemia beta. Embora mais de 700 hemoglobinas variantes tenham sido descritas, apenas a forma homozigótica para HbS apresenta expressão clínica mais evidente; no entanto, as formas heterozigóticas HbAS e HbSC também representam um problema de saúde pública. Em geral, os indivíduos heterozigóticos desconhecem o fato de serem portadores assintomáticos (AS, AC) e, por isso, facilitam a propagação desses genes anômalos e sua interação com outras hemoglobinas variantes, talassemias, enzimopatias e esferocitoses. Como medida de prevenção e controle das hemoglobinopatias no Brasil, o Ministério da Saúde instituiu a portaria 822/01, que inclui a triagem de hemoglobinopatias no programa nacional de triagem neonatal (PNTN). O objetivo deste trabalho foi analisar a prevalência das hemoglobinopatias em crianças nascidas no período de janeiro a junho de 2003 no estado de Santa Catarina. Do total de 40.028 amostras analisadas, 399 (1%) apresentaram hemoglobinopatias, e, dessas, 88,47% apresentaramm o fenótipo AS; 7,76% AC; 2,25% AD; 0,75% SS e 0,5% SC. A triagem de hemoglobinopatias é uma análise importante para a prevenção das hemoglobinopatias, as quais representam um problema de saúde pública.

A Reliable Screening Protocol for Thalassemia and Hemoglobinopathies in Pregnancy

Primary screening for thalassemia and hemoglobinopathies usually involves an accurate blood count using an expensive electronic blood cell counter. A cheaper alternative method was tested by using a modified osmotic fragility (OF) test and a modified dichlorophenolindophenol (DCIP) test. Altogether 423 pregnant Thai women participated in this project. Hemoglobin patterns and globin genotypes were determined using an automated high-performance liquid chromatography analyzer and polymerase chain reaction analysis of α- and β-globin genes. Among the 423 subjects, 264 (62.4%) carried thalassemia genes. The combined OF and DCIP tests detected all pregnant carriers of the 3 clinically important thalassemias, ie, α0-thalassemia, β-thalassemia, and hemoglobin E with a sensitivity of 100.0%, specificity of 87.1%, positive predictive value of 84.5%, and negative predictive value of 100.0%, which show more effectiveness than these values for the standard method based on RBC counts. A combination of modified OF and DCIP tests should prove useful and applicable to prenatal screening programs for thalassemia and hemoglobinopathies in communities with limited facilities and economic resources.

A Reliable Screening Protocol for Thalassemia and Hemoglobinopathies in Pregnancy

Primary screening for thalassemia and hemoglobinopathies usually involves an accurate blood count using an expensive electronic blood cell counter A cheaper alternative method was tested by using a modified osmotic fragility (OF) test and a modified dichlorophenolindophenol (DCIP) test. Altogether 423 pregnant Thai women participated in this project. Hemoglobin patterns and globin genotypes were determined using an automated high-performance liquid chromatography analyzer and polymerase chain reaction analysis of alpha- and beta-globin genes. Among the 423 subjects, 264 (62.4%) carried thalassemia genes. The combined OF and DCIP tests detected all pregnant carriers of the 3 clinically important thalassemias, ie, alpha0-thalassemia, beta-thalassemia, and hemoglobin E with a sensitivity of 100.0%, specificity of 87.1%, positive predictive value of 84.5%, and negative predictive value of 100.0%, which show more effectiveness than these values for the standard method based on RBC counts. A combination of modified OF and DCIP tests should prove useful and applicable to prenatal screening programs for thalassemia and hemoglobinopathies in communities with limited facilities and economic resources.

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.

Prenatal Carrier Screening for Genetic Conditions

After completing this article, readers should be able to: 1. Discuss the benefits and limitations of carrier screening. 2. Describe the recommendations for screening for hemoglobinopathies. 3. List the genetic disorders for which carrier screening is available for individuals of Ashkenazi Jewish ancestry. 4. Describe the recommendations for cystic fibrosis carrier screening. Carrier screening for hemoglobinopathies, Tay-Sachs and Canavan diseases, and more recently, cystic fibrosis has been incorporated into routine obstetric care. These genetic disorders are autosomal recessive, and when both members of a couple are carriers, there is a 25% risk of having an affected child in each pregnancy. Although many states routinely screen newborns for sickle cell disease and cystic fibrosis, recognition that a couple is at increased risk for having a child with one of these disorders permits a wider array of options, including antenatal diagnosis and termination of an affected fetus. In some cases, identification of an affected fetus allows a couple, their obstetrician, neonatologist, pediatrician, and pediatric specialists to prepare for the birth of an affected fetus. Screening completed prior to conception provides couples with additional reproductive options to consider, including donor gametes, preimplantation genetic diagnosis, and adoption if they choose to reduce their risk of having an affected child. As a result of the Human Genome Project and advances in technology, DNA-based tests can be used for carrier screening and prenatal diagnosis for many inherited conditions. In addition to screening for sickle cell disease, thalassemia, and Tay-Sachs disease, carrier screening now is available for cystic fibrosis, Canavan disease, and other disorders that are more common in individuals of Ashkenazi Jewish ancestry. Carrier screening recommendations for these genetic conditions is based on a person’s ethnicity. However, the importance of family history cannot be underestimated. The family history is used to determine whether an individual or couple is at increased …

Multiplex allele-specific PCR assay for differential diagnosis of Hb S, Hb D-Punjab and Hb Tak

Background: Apart from hemoglobin (Hb) E, Hb D-Punjab [β121(GH4)Glu–Gln] and Hb Tak [β147Term-Thr] are the two most common β-chain variants among the Asian population. These two Hb variants have similar alkaline electrophoretic mobilities and HPLC profiles as those of the Hb S [β6(A3)Glu–Val]. Differential diagnosis of these clinically relevant hemoglobinopathies is therefore problematic. Direct detection of the β-globin gene mutations would be another diagnostic alternative. Methods: A simultaneous DNA diagnosis of the three Hb variants was developed based on the multiplex allele-specific polymerase chain reaction (PCR) approach. The method was validated on 10 carriers of Hb D-Punjab, 5 carriers of Hb Tak, 2 carriers of Hb S and 50 normal individuals of Thai origin. Results: The three abnormal Hbs could be correctly diagnosed with the simultaneous PCR approach, and a complete concordance with results using other established methods was obtained. Conclusions: The multiplex allele-specific PCR approach developed should prove useful in complementing routine Hb analysis for differential diagnosis of these three common Hb variants and should facilitate a program of hemoglobinopathy screening in the region.

Prevalence of abnormal hemoglobins in newborns in Natal, Rio Grande do Norte, Brazil

Hemoglobinopathies are among the most prevalent hereditary diseases in humans. Studies in different areas of Brazil have identified the prevalence of S and C abnormal hemoglobins. The study analyzed 1,940 cord blood samples of newborns from maternity hospitals in Natal, Rio Grande do Norte State, to investigate the prevalence of abnormal hemoglobins. All samples were submitted to cellulose acetate electrophoresis using a Tris-EDTA-borate buffer at pH 8.5. Electrophoresis in agar gel pH 6.2 was performed on samples presenting abnormal hemoglobin. Some 37 (1.91%) of the newborns presented hemoglobinopathies, as follows: 29 (1.50%) sickle cell trait (Hb FAS), 6 (0.31%) heterozygous Hb C (Hb FAC), one (0.05%) homozygous Hb S (Hb FS), and one (0.05%) Hb Barts suggestive of alpha thalassemia. The results show the need to implement screening for hemoglobinopathies in the neonatal population.

Automated computer result reporting for haemoglobinopathy screening.

The anticipated introduction of universal antenatal screening can be expected to increase the workload of haemoglobinopathy laboratories throughout the country. We have devised a rule-based system to process those results that does not require skilled interpretation, thereby freeing staff time for more specialized work. The system relies on a calculated test to create a total haemoglobin peak value, which incorporates the values for HbA, HbA2 and HbF, the MCV and MCH from the full blood count. Each parameter has a series of defined ranges which, when subjected to an interpretation process within the laboratory computer system, generates an automated result text for the sample. During a 6-month verification period, the automated result interpretation system in conjunction with laboratory information systems (LIS) validation reduced the number of samples requiring manual review by 60%. The system was found to be 100% sensitive and 61.8% specific. We feel that the current specificity is acceptable in order to maintain a safe system. The ability to concentrate on potentially abnormal results will allow laboratories and health care workers more time to develop appropriate and timely frameworks to deal with abnormal results.

Hemoglobinopathies, G6PD Deficiency, and Hereditary Elliptocytosis in Bahrain

The native population of Bahrain has a high prevalence of hemoglobinopathies and G6PD deficiency, probably as a result of past malarial endemism. We used the Biorad-Variant hemoglobin testing system for primary screening of hemoglobinopathies in 20,000 individuals. Hemoglobin abnormalities were detected in 7,206 (36.3%) cases.

A pilot study of 'fast track' antenatal screening for haemoglobinopathies.

The NHS Plan launched in 2000 advocated a linked antenatal and neonatal screening programme for haemoglobinopathies. Currently screening practices vary widely across the UK and patient sampling is generally performed in a hospital setting. The process is flawed and frequently fails to provide accurate and timely information. In this study we demonstrate that organisational changes can improve the efficiency and quality of screening. The primary care screening process described here has increased partner testing rates and allowed early identification of at risk couples.

Regional Experience with Newborn Screening for Sickle Cell Disease, Other Hemoglobinopathies and G6PD Deficiency

Newborn screening for sickle cell disease, other hemoglobinopathies and G6PD deficiency is one of the most important means of decreasing mortality and morbidity in high prevalence areas. Nine years experience in newborn screening in Qatif Central Hospital are summarized. All newborns in Qatif Central Hospital had cord blood screening for sickle cell disease, other hemoglobinopathies and G6PD deficiency using alkaline and electrophoresis, agar gel electrophoresis for sickle cell disease and fluorescent screening technique for G6PD deficiency. Families of infants with minor hemoglobinopathies and G6PD deficiency were informed about the results in the well baby clinic. From December 1992 to December 2001, 24 012 newborn were screened. 21 858 (91.03%) were Saudi and 2154 (8.97%) were non-Saudi. In the Saudi hemoglobin electrophoresis patterns, AF (normal) was found in 49.52%, hemoglobin FS (sickle cell disease) + FS Bart s (sickle cell disease with alpha thalassemia) in 2.57%, hemoglobin AFS (sickle cell trait) + AFS Bart s (sickle cell trait with alpha thalassemia) in 21.14%, and alpha thalassemia (based on elevated Bart s hemoglobin > or = 2%) in 35.68%. G6PD deficiency was found in 37.02% and 21.27% in males and females, respectively. Of 563 Saudi newborn with a presumptive diagnosis of sickle cell disease, 48 (8.5%) did not come to the hematology clinic or were not contactable. The diagnosis of sickle cell anemia or sickle thalassemia was confirmed in 513 patients, and 2 cases were found to have sickle cell trait on repeat testing. Many parents found it hard to accept the initial diagnosis and the resulting impact on their relationship with one another. Prevention and early identification of sickle cell disease, other major hemoglobinopathies and G6PD deficiency remains the cornerstone of management of these diseases. The main barriers to successful neonatal screening for hemoglobinopathies are the level of the education and deficiency in manpower. We recommend including newborn screening for hemoglobinopathies and G6PD deficiency in the national hypothyroidism screening program in the eastern province and the establishment of a special center for hemoglobinopathies with a high standard of medical care in Qatif.