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Objective: The capillary zone electrophoresis (CZE) and highperformance liquid chromatography (HPLC) methods were compared in terms of HbA2 measurement for the assessment of hemoglobinopathies. Materials and Methods: CZE was compared with HPLC for the evaluation of patients without hemoglobinopathy (n=321), with β-thalassemia trait (n=113), and with common (HbD-Punjab, E, C, S/A, and S/S) and rare (HbS/D, O-Arap, Lepore, G-Coushata, Setif, Hamadan, Q-Iran, and H) variants (n=21). The reference range for HbA2 was determined by CZE. Results: Among patients without hemoglobinopathy, the median (2.5th-97.5th percentiles) values were 97.4% (97.0-98.0%) and 97.5% (96.6-98.4%) for HbA (p=0.060) and 2.4% (1.6-3.0%) and 2.5% (1.6-3.1%) for HbA2 (p<0.001) by HPLC and CZE, respectively. The reference range for HbA2 was 1.6-3.1% by CZE. In the comparison of methods for HbA2, there was a constant error of 0.255 (confidence interval: 0.062-0.448) and bias of 0.10% (limit of agreement: 0.33- 0.53), and higher values were obtained with CZE. A strong correlation was observed between the methods (r=0.782). Interrater agreement was almost perfect for clinical diagnosis (=0.911). The two methods detected and identified the common variants similarly. All rare variants, except HbH by HPLC and HbS/D by CZE, were detected as separate peaks by both methods. Conclusion: The two methods were in agreement regarding the preliminary identification of β-thalassemia patients. Different Hb variants were detected by both methods but with possible methodological interference for HbA2 measurements. CZE is a reliable and simple alternative for the evaluation of hemoglobinopathies. The standardization of HbA2 measurements should be prioritized as more techniques become available in routine laboratory practice [ABSTRACT FROM AUTHOR]

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. 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 HbA2 gene in heterozygosis, which resulted in the expression of the structural hemoglobinopathy known as hemoglobin Bari. 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. [ABSTRACT FROM AUTHOR]

* Context.--Underuse of laboratory testing has been previously investigated in preselected populations, such as documented malpractice claims. However, these numbers might not reflect real-life situations. Objective.--To evaluate the underuse and misuse of laboratory follow-up testing in a real-life hospital patient population with microcytic anemia, using laboratory results ordered during routine patient care. Design.--From all patients in whom a microcytic anemia was detected during routine diagnostics in 2018, all available laboratory data were collected and screened for appropriateness of diagnostic workup of iron deficiency and thalassemia. Subgroup analysis was performed for patient groups with mean corpuscular volume values 75 to 79 µm³ (group 1), 65 to 74 µm³ (group 2), and <65 µm³ (group 3). Results.--A total of 2244 patients with microcytic anemia were identified. Follow-up testing for iron deficiency was not performed in 761 cases (34%). For inconclusive ferritin levels due to elevated C-reactive protein results (n = 336), reticulocyte hemoglobin content or soluble transferrin receptor levels were missing in 86 cases (26%). In patients with suspected thalassemia (n = 127), follow-up testing for hemoglobin variants was not performed in 70 cases (55%). Subgroup analysis showed that the frequency of underuse of iron status as well as thalassemia/hemoglobinopathy testing decreased from group 1 to group 3. When considering relevant preexisting anemia diagnoses, laboratory tests were underused in 904 cases (40.3%). Conclusions.--Because 40% (n = 904) of the patients with microcytic anemia were potentially not followed up correctly, laboratory specialists are advised to act by implementing demand management strategies in collaboration with clinicians to overcome underuse of laboratory tests and to improve patient safety. [ABSTRACT FROM AUTHOR]

Objective: To report the diagnostic challenges of newborn screening for abnormal haemoglobins. Setting: Cord blood samples from 13 hospitals in southwest Jamaica taken in 2008–2019. Methods: Blood spots, collected from the umbilical cord, were analysed by high pressure liquid chromatography (HPLC) to reveal phenotypes for HbSS and HbCC, but genotype confirmation may require parental studies or gene sequencing. Such cases that were successfully traced were analysed in this follow-up study. Results: HPLC screening of 121,306 samples detected HbAS in 11,846 (9.8%), HbAC in 4508 (3.7%) and other electrophoretic abnormalities in 1090 babies. Among 101 previously unconfirmed cases, 34/90 (38%) with HPLC evidence of a HbSS phenotype had other genotypes, and 7/11 (64%) with a HbCC phenotype had other genotypes. Syndromes from the interaction of β thalassaemia occurred in 112 babies (85 with HbS, 27 with HbC) and of genes for hereditary persistence of fetal haemoglobin (HPFH) in 18 (12 with HbS, 6 with HbC). Variants other than HbS and HbC occurred in 270 babies, 16 in combination with either HbS or HbC, and 254 as traits. Most variants are benign even when inherited with HbS, although HbO Arab, HbD Punjab, or Hb Lepore Washington, which occurred in 6 cases, may cause sickle cell disease. Conclusions: Genes for β thalassaemia and HPFH are common in western Jamaica and when associated with HbS may present diagnostic challenges in newborns, as HbF and HbA2 have not reached diagnostic levels. Family and DNA studies may be necessary for genotype confirmation. [ABSTRACT FROM AUTHOR]

Hemoglobinopathies are the most common monogenic disorders in the world with an ever increasing global disease burden each year. As most hemoglobinopathies show recessive inheritance carriers are usually clinically silent. Programmes for preconception and antenatal carrier screening, with the option of prenatal diagnosis are considered beneficial in many endemic countries. With the development of genetic tools such as Array analysis and Next Generation Sequencing in addition to state of the art screening at the hematologic, biochemic and genetic level, have contributed to the discovery of an increasing number of rare rearrangements and novel factors influencing the disease severity over the recent years. This review summarizes the basic requirements for adequate carrier screening analysis, the importance of genotype–phenotype correlation and how this may lead to the unrevealing exceptional interactions causing a clinically more severe phenotype in otherwise asymptomatic carriers. A special group of patients are β‐thalassemia carriers presenting with features of β‐thalassemia intermedia of various clinical severity. The disease mechanisms may involve duplicated α‐globin genes, mosaic partial Uniparental Isodisomy of chromosome 11p15.4 where the HBB gene is located or haplo‐insufficiency of a non‐linked gene SUPT5H on chromosome 19q, first described in two Dutch families with β‐thalassemia trait without variants in the HBB gene. [ABSTRACT FROM AUTHOR]

Introduction: Hemoglobinopathies are major public health problems worldwide. Accurate laboratory diagnosis of the carrier is essential, which includes initial screening, Hb analysis, and DNA analysis. For the first time, we have developed a single‐tube quality control (QC) sample for these laboratory tests. Methods: The QC sample was made from a lyophilized mixture of the stabilized hemolysate with carbon monoxide saturation and the white blood cells of known thalassemia mutations. Homogeneity and stability were examined by Hb and DNA analyses on day 0 and every month for 12 months, at room temperature, 4°C, and −20°C. A preliminary proficiency testing (PT) program for hemoglobinopathies using this single QC material was developed. Results: Hemoglobin (Hb) and DNA analyses of a single‐tube QC sample demonstrated satisfactory results of Hb analysis for at least five months and DNA analysis for at least one year of storage at −20°C. The results obtained from a preliminary PT program on five expert laboratories confirmed that a single tube QC sample prepared could be used as a PT item with various Hb and DNA analyses methods. Conclusion: A single lyophilized control sample has been generated for use in hemoglobinopathies' internal and external quality control program. Unlike other available control materials, which are used for individual testing, a single‐tube QC sample generated can be used to control the pre‐analytical and analytical processes of both Hb and DNA analyses and is suitable for use in the PT program of hemoglobinopathies. [ABSTRACT FROM AUTHOR]

Background: High performance liquid chromatography (HPLC) is the most commonly used method for detection and quantitative estimation of hemoglobin variants. Hemoglobinopathies are amongst the most common genetically inherited disorders, however, the exact magnitude of different hemoglobinopathies is obscure in India. This study was done with the aim of analyzing the different findings in HPLC using D-10 analyzer and evaluating the spectrum of different hemoglobin disorders in a hospital-based population of South Delhi. Such a prevalence study would be useful to review the various strategies that can be implemented for effective control and prevention of these disorders. Methods: A hospital based descriptive observational study was conducted in which all OPD and IPD patients who were advised HPLC during their clinical workup were included. Analysis of EDTA blood samples was done by Bio Rad D10 Dual program HPLC instrument. The exact percentage of HbA, HbA2, HbF and any other variant hemoglobin was estimated. Presumptive identification of hemoglobin variants was made primarily by their percentage, retention time (RT) and peak characteristics. HPLC findings were correlated with the clinical history, family history and the CBC and peripheral smear findings in all cases. Results: On HPLC analysis, 79% of the patients had no abnormality detected and the report was within normal limits. The commonest hemoglobinopathy was Beta Thalassemia Trait followed by HbE trait. The other hemoglobinopathies detected were HbD Punjab Heterozygous (3 cases, 0.5%), Beta thalassemia homozygous (3 cases, 0.5%), Sickle cell Heterozygous (2 cases, 0.3%), HbJ Meerut Heterozygous (2 cases, 0.3%). One case each of Sickle cell Homozygous (0.15%), Compound Heterozygous HbS/beta thalassemia trait (0.15%), HbE Homozygous (0.15%), Compound Heterozygous HbE/beta thalassemia trait (0.15%), and Homozygous delta beta thalassemia (0.15%) were also diagnosed. Conclusion: This study gives an important insight to the present day scenario of hemoglobinopathies in patients in South Delhi in relation to the hematological profile. It highlights the chromatogram findings of different hemoglobinopathies on the D10 analyzer. The comprehensive data obtained by such series can help in the formulation and development of infrastructure and policies for hemoglobinopathy prevention, diagnosis and management. [ABSTRACT FROM AUTHOR]

The article focuses on the impact of Voxelotor, an oral sickle hemoglobin inhibitor, on the quantitation of HbS levels in a patient with sickle cell disease. Topics include the patient's clinical presentation, the challenges in accurately quantifying HbS levels using high-performance liquid chromatography (HPLC) due to Voxelotor treatment, and the importance of providing information about the patient's drug treatment to ensure proper laboratory test interpretation.

A female patient aged 47 years presented with a hemoglobin A1c (HbA1c) level of 54.6%, as measured by ion-exchange high-performance liquid chromatography (HPLC), and a glucose level of 106 mg/dL. The HbA1c was re-evaluated using a turbidimetric inhibition immunoassay and found below the level of detection. Hemoglobinopathy testing led to the identification of a hemoglobin variant consistent with Hb Raleigh, in which a valine → alanine substitution on the beta chain effects a charge difference, resulting in coelution with HbA1c on HPLC and a spuriously high reading. Many Hb variants may interfere with HbA1c measurement and generate misleading results. The unique properties of Hb Raleigh may give rise to analytical errors when evaluating HbA1c using 2 different methods—molecular charge–based (eg, HPLC) and molecular structure–based (eg, immunoassay)—yielding diametrically opposed results. Consequently, recognition and diagnosis of this entity are essential in patients with Hb Raleigh, especially when monitoring long-term glucose control. [ABSTRACT FROM AUTHOR]

Background: Antenatal screening is vital to identifying couples at risk of having children with a clinically significant haemoglobinopathy. In Australia, immigration is increasing carrier incidence. Methods: A retrospective analysis was performed of full blood count, high-performance liquid chromatography and haemoglobin electrophoresis of women and their partners who underwent antenatal haemoglobinopathy screening over three years at a major NSW laboratory. Genetic testing results were included where available. Results: One thousand six hundred and twenty-eight women and 729 male partners were screened at a median gestation of 14 weeks. 8.2% of women had a clinically significant result, with a median 16-day interval to partner testing. In 35% of couples screened simultaneously, the partner did not require testing. Genetic confirmatory testing was performed in 65% of high risk couples. Conclusion: There was a significant delay to antenatal haemoglobinopathy screening for mothers, limiting time for genetic diagnosis, prenatal diagnosis and management of affected pregnancies. Screening should be performed earlier. Simultaneous couple testing is not cost-effective. [ABSTRACT FROM AUTHOR]

Aim: To know the patterns of hemoglobinopathies and their prevalence in Kerbala society by using high performance liquid chromatography and to conclude if there is any correlations between different hematological parameters in Hemoglobinopathy patients. A total of 70 cases studied from 16th of February 2018 to 20th of June 2018 for hemoglobin variant analysis at the teaching labrotarioes of Al- Hussseini Teaching hospital which were studied for patterns of hemoglobinopathies. When the samples were received, Complete Blood Counts including: Hemoglobin concentration, Total White blood cells count (WBC), Mean Cell Volume (MCV), Mean Cell Haemoglobin (MCH), Mean Cell Hemoglobin Concentration (MCHC), Serum ferritin, Total Iron Binding Capacity ( TIBC), Hemoglobin H (HbH) preparation were done. Out of total 70 patients screened for patterns of hemoglobinopathies the result of the study revealed that 48 Patients which represent(68.57 %) of total patients had B-thalassemia trait which form the predominant percentage of patients with haemoglobinopathy, 11.85% of patients had sickle cell trait, 5.71% of them had B-Thalassemia Major, 4.29% had Hb S/B+Thalassemia Trait, 2.86% had HbS/Alpha thalassemia trait, 1.43% of them had Hb S homozygosity, 1.43% Alpha thalassemia trait, 1.43% had D-Los Anglos, 1.43% had HbS/B+ Thalassemia trait and 1.43% had HbC/B-Thalassemia trait. [ABSTRACT FROM AUTHOR]

The article presents a case study of a female infant with splenic rupture with multiple etiologies. It notes the complete blood count (CBC) and echocardiogram for atrial septal defect, transferred to the neonatal intensive care unit and low hemoglobin, with the examination of a had ultrasound and abdominal ultrasound.

Introduction: The hemoglobinopathies pose a significant health burden in India. Apart from the β thalassemias and sickle cell disorders, α thalassemias and structural hemoglobin variants are also common. Here we have reviewed the phenotypic and molecular diversity of hemoglobinopathies encountered at a referral center in western India over a period of 15 years. Materials and Methods: Screening for hemoglobinopathies was done using HPLC and cellulose acetate electrophoresis. Molecular characterization was done using Covalent Reverse Dot Blot Hybridization (CRDB), Amplification Refractory Mutation System (ARMS), GAP PCR and direct DNA sequencing. Results: The study includes 31 075 individuals who were referred for diagnosis of hemoglobinopathies and prenatal diagnosis. Of these 14 423 individuals showed various hemoglobin abnormalities. Beta genotyping in 5615 individuals showed the presence of 49 β thalassemia mutations. 143 β thalassemia heterozygotes had normal or borderline HbA2 levels. We identified three δ gene mutations (HbA2 Pellendri, HbA2 St.George, HbA2 Saurashtra) in β thalassemia heterozygotes leading to normal HbA2 levels. The commonest defects among the raised Hb F determinants were Gγ(Αγδβ)0 Indian inversion and the HPFH‐3 Indian deletion. A total of 312 individuals showed the presence of α thalassemia, of which 12.0% had a single α gene deletion (−α/αα). HbH disease was identified in 29 cases with 10 different genotypes. Alpha globin gene triplication was seen in 2.1% of β thalassemia heterozygotes with a thalassemia intermedia phenotype. Seven unusual α chain variants and eight uncommon β chain variants were identified. Conclusion: The repertoire of molecular defects seen in the different globin genes will be valuable for management and control of these disorders both in India as well as in other countries where there is a huge influx of migrant populations from India. [ABSTRACT FROM AUTHOR]

The article presents a case study that involves an asymptomatic neonate with reduced peripheral oxygen saturations (SpO2), whereby the patient's father has a confirmed rare haemoglobinopathy, haemoglobin Titusville. It reports that Haemoglobin Titusville is a low-oxygen affinity haemoglobinopathy involving a single nucleotide change from G to A at codon 94 of the alpha globin gene.

Hemoglobin [Hb] J-Singapore [a79(EF8)Ala→Gly, GCG>GGG] is a very rare α-globin chain variant. In the present study, the authors reported, for the first time, the Hb J-Singapore in a 31-year-old Thai pregnant woman. She was seen by an obstetrician at her fifteenth week of gestation. Based on routine antenatal thalassemia and hemoglobinopathy screening, her Hb analysis was performed by high performance liquid chromatography [HPLC] and the abnormal Hb peak with a value of 23.6% was observed at the retention time of 1.83 minutes. The abnormal Hb peak was also found at zone 12 of capillary electrophoresis [CE] electrophoregram, which was similar to the peak of Hb Bart's and Hb J-Buda. The direct DNA sequencing revealed the GCG>GGG mutation at codon 79 of α2-globin gene as previously described for Hb J-Singapore. In addition, the developed multiplex allele specific polymerase chain reaction [MAS-PCR] showed the 63 2 bp amplified fragment from Hb J-Singapore allele. Thus, the knowledge and understanding of this hemoglobinopathy will be used to assist in diagnosis, management, and counseling for needed patients. [ABSTRACT FROM AUTHOR]

Introduction Differentiation of homozygous hemoglobin (Hb) E with and without α0-thalassemia is subtle on routine hematological ground. We examined in a large cohort of homozygous Hb E if the level of Hb A2 is helpful. Methods A total of 592 subjects with homozygous Hb E were recruited from ongoing thalassemia screening program. Additionally, five couples at risk of having fetuses with Hb Bart's hydrops fetalis who were homozygous Hb E were also investigated. Hb analysis was performed using capillary electrophoresis system. Globin genotypes were defined by DNA analysis. Results Subjects were classified into four groups including pure homozygous Hb E (n=532), homozygous Hb E/α0-thalassemia (n=48), Hb Constant Spring EE Bart's disease (n=8), and Hb EE Bart's disease (n=4). The levels of Hb A2 were found, respectively, to be 4.97±0.69, 6.64±1.02, 4.86±0.87, and 7.60±1.04%. Among five couples at risk, α0-thalassemia was identified in three subjects with Hb A2>6.0%. Conclusions Increased Hb A2 level is a useful marker for differentiation of homozygous Hb E with and without α0-thalassemia. This should lead to a significant reduction in number of referral cases of homozygous Hb E for molecular testing of α0-thalassemia in routine practice. [ABSTRACT FROM AUTHOR]

Hemoglobinopathies are caused by point mutation in globin gene that results in structural variant of hemoglobin. While 7 % of world populations are carrier of hemoglobinopathies, the prevalence of the disease varies between 3 to 17 % across different population groups in India. In a diagnostic laboratory, alkaline gel electrophoresis and cation exchange-based HPLC (CE-HPLC) are most widely used techniques for characterization of hemoglobin variants. In the above methods, the differential surface charge of hemoglobin molecule in variants is exploited for their characterization. Sometime, co-migration of variants in gel electrophoresis and co-elution or elution with unknown retention time in automated CE-HPLC might lead to ambiguity in the analysis of hemoglobinopathies. Under such circumstances, it is necessary to use other analytical methods that provide unambiguous results. Mass spectrometry-based proteomics approach and DNA sequence analysis are examples of such alternative methods. In the present study, liquid chromatography coupled to mass spectrometry has been used for three commonly observed variants in India, e.g., HbE, HbQ India and HbD Punjab that appeared with inappropriate results in the conventional analysis. A customized hemoglobin variant database has been used in the mass spectrometry-based analysis of those three variants. Mass spectrometry-based proteomics approach was used to analyze above variant sample accurately. [ABSTRACT FROM AUTHOR]

Hemoglobinopathies are one of the major problems in Pakistan. A retrospective analysis of blood samples of 2731 patients from 2010 to 2014 was done at National Institute of Blood Disease & Bone Marrow Transplantation for the workup of anemia or other blood-related disorders. Whole blood samples in EDTA were collected; complete blood counts with peripheral smears were prepared. Hemoglobin (Hb) electrophoresis on Genio was performed at alkaline pH. Samples showing borderline results were further tested by high-performance liquid chromatography or for specific mutation analysis by ARMS-PCR. Out of total 2731, 935 (34.2%) patients had hemoglobinopathies. Out of these 935 patients who had hemoglobinopathies, beta thalassemia minor 51.8%, beta thalassemia major 24.1%, HbD trait 6.7, sickle/ beta thalassemia 4.5%, sickle cell disease 3.9%, HbE trait 1.9%, and sickle cell trait 1.7% were most common hemoglobinopathies. Less prevalent were delta/beta thalassemia, HbE homozygous, HbD homozygous, and HbH disease. [ABSTRACT FROM AUTHOR]

Background HbA1c is used in the diagnosis and monitoring of diabetes mellitus (DM). Interference from hemoglobin variants is a well-described phenomenon, particularly with HPLC-based methods. While immunoassays may generate more reliable HbA1c results in the presence of some variants, these methods are susceptible to negative interference from high concentrations of HbF. We report a case where an accurate HbA1c result could not be obtained by any available method due to the presence of a compound hemoglobinopathy. Methods HbA1c was measured by HPLC, immunoassay, and capillary electrophoresis. Hemoglobinopathy investigation consisted of a CBC, hemoglobin fractionation by HPLC and electrophoresis, and molecular analysis. Results HbA1c analysis by HPLC and capillary electrophoresis gave no result. Analysis by immunoassay yielded HbA1c results of 5.9% (Siemens DCA 2000 +) and 5.1% (Roche Integra), which were inconsistent with other markers of glycemic control. Hemoglobinopathy investigation showed HbC with the hereditary persistence of fetal hemoglobin-2 Ghana deletion. Conclusion Reliable HbA1c results may be unobtainable in the presence of some hemoglobinopathies. HPLC and capillary electrophoresis alerted the laboratory to the presence of an unusual hemoglobinopathy. Immunoassays generated falsely low results without warning, which could lead to missed diagnoses and under treatment of patients with DM. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Laboratory Medicine / Laboratoriums Medizin is the property of De Gruyter and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Laboratory Medicine / Laboratoriums Medizin is the property of De Gruyter and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction Capillary zone electrophoresis (CZE) at alkaline pH is one of the techniques used for hemoglobinopathy screening. In this study, an evaluation of the performance of a lower throughput CZE instrument, the Sebia Minicap Flex Piercing system, for this purpose is reported for the first time. Methods The analytical performance of the Sebia Minicap Flex Piercing system was evaluated. Furthermore, a method comparison between the Sebia Minicap Flex Piercing and two HPLC methods, that is, the Bio-Rad Variant Classic™ and the Bio-Rad D-10™ systems was performed by measuring samples with and without clinically relevant hemoglobin disorders. Results The analytical performance was acceptable for the determination of HbA, HbA2, HbS, and HbF, with an imprecision ≤2.0%. Method comparison showed a linear correlation for HbA2, HbF, and HbS measurements. Clinical concordance was acceptable when comparing CZE and HPLC. Conclusions Lower throughput CZE using the Sebia Minicap Flex Piercing can be used for precise and accurate first line screening and follow-up of hemoglobinopathies. [ABSTRACT FROM AUTHOR]

Hb Handsworth is a rare α-globin structural variant caused by a missense mutation either on the α2 or α1-globin gene ( HBA2 or HBA1: c.55G>C, p.Gly18Arg). This variant might be erroneously diagnosed as Hb S unless secondary confirmative tests are carried out. We encountered a child with a prominent peak eluting in the ' S' window on high-performance liquid chromatography ( HPLC). Sickle solubility test, gel electrophoresis, and selective direct nucleotide sequencing of α1, α2, and β globin genes were performed on the patient's sample. In addition, previous HPLC results on a cord blood sample were retrieved. Sickle solubility test was negative. Gel electrophoresis revealed a band migrating at the S region with an extra faint band seen on acid gel electrophoresis. Molecular analysis of α2 globin gene revealed heterozygous state of Hb Handsworth. Hb Handsworth is a rare variant that can mimic Hb S on HPLC. Failure to recognize this rare variant in regions where Hb S is highly prevalent may result in serious misdiagnosis and subsequent incorrect genetic counseling. [ABSTRACT FROM AUTHOR]

The hemoglobinopathies encompass a heterogeneous group of disorders associated with mutations in both the alpha-globin and beta-globin genes. Increased immigration of high-risk populations has prompted the implementation of prenatal and newborn screening programs for hemoglobinopathies across Europe and North America. In Canada, the UK, and other European countries, prenatal screening to identify hemoglobinopathy carriers and offer prenatal diagnostic testing to couples at risk is linked to newborn screening, while in the United States, it is still not universally performed. The structure of screening programs, whether prenatal or postnatal, universal or selective, varies greatly among these countries and within the United States. The laboratory methods used to identify hemoglobinopathies are based on the prevalence of hemoglobinopathies within the population and the type of screening performed. Advances in molecular testing have facilitated the diagnosis of complex thalassemias and sickling disorders observed in ethnically diverse populations. This review summarizes the current approaches and methods used for carrier detection, prenatal diagnosis, and newborn screening. [ABSTRACT FROM AUTHOR]

To evaluate the analytical performance of a new capillary electrophoresis instrument, the Capillarys 2 Flex piercing (Sebia, France), allowing the separation and quantitative estimation of the different haemoglobin fractions from whole blood, in capped primary tube.The analytical precision for the determination of HbA2 and HbF percentages was satisfactory and within the range of previously published results for HPLC methods. The correlation between Capillarys 2 Flex Piercing and Bio-Rad Variant II HPLC system showed a linear correlation for HbA2, HbF and HbS measurements, and the analysis interpretation was the same whatever the method used. Conversely to HPLC method, the capillary's electrophoresis technology allowed HbE and Hb Lepore fraction separation from HbA2. We showed that the Capillarys 2 Flex Piercing is suitable for haemoglobinopathies diagnosis and screening and offers an excellent alternative to HPLC techniques as a first-line method or for confirmatory analysis. [ABSTRACT FROM AUTHOR]

Commonly used methods for assay of haemoglobin A(1c) (HbA(1c)) are susceptible to interference from the presence of haemoglobin variants. In many systems, the common variants can be identified but scientists and pathologists must remain vigilant for more subtle variants that may result in spuriously high or low HbA(1c) values. It is clearly important to recognize these events whether HbA(1c) is being used as a monitoring tool or, as is increasingly the case, for diagnostic purposes. We report a patient with a rare haemoglobin variant (Hb Sinai-Baltimore) that resulted in spuriously low values of HbA(1c) when assayed using ion exchange chromatography, and the steps taken to elucidate the nature of the variant. [ABSTRACT FROM AUTHOR]

Summary Measurement of the Haemoglobin F in red cell haemolysates is important in the diagnosis of δβ thalassaemia, hereditary persistence of fetal haemoglobin (HPFH) and in the diagnosis and management of sickle cell disease. The distribution of Hb F in red cells is useful in the diagnosis of HPFH and in the assessment of feto-maternal haemorrhage. The methods of quantifying Hb F are described together with pitfalls in undertaking these laboratory tests with particular emphasis on automated high-performance liquid chromatography and capillary electrophoresis. [ABSTRACT FROM AUTHOR]

Summary Introduction: The α-chain variant Hb Q-India (c.193G>C) is caused by a point mutation GAC→CAC at codon 64 of the α1 globin gene and is clinically silent. Point mutations can be diagnosed easily by many simple polymerase chain reaction (PCR) techniques including PCR-restriction digest, but for Hb Q-India the restriction digest has never been described. In this work we aimed to develop a restriction enzyme digestion assay for DNA diagnosis of Hb Q-India, in order to increase the panel of restriction enzymes used in DNA diagnosis of haemoglobinopathies and also as a simple cheap alternative to the ARMS-PCR method. Methods: A restriction enzyme digestion assay was designed for diagnosis of Hb Q-India using the restriction enzyme EaeI enzyme as the Hb Q-India mutation abolishes the recognition site of this enzyme. Patients were screened for an abnormal haemoglobin by high performance liquid chromatography (HPLC) and those had an abnormal peak with a retention time between 4.7 and 4.8 minutes were selected for diagnosis at the molecular level. The α1 globin gene was amplified in 12 cases with a presumed diagnosis of Hb Q-India by HPLC and isoelectric focusing (IEF), and the amplified products were subjected to the EaeI digestion. Results: All the 12 cases were diagnosed positive (100%) for Hb Q-India by the EaeI restriction enzyme digest. They were heterozygotes for the mutation. Conclusion: EaeI restriction enzyme digestion can be used as a simple and robust alternative method to ARMS-PCR for DNA diagnosis of Hb Q-India. The EaeI restriction enzyme can be added to the panel of restriction enzymes used in the DNA diagnosis of the abnormal Hb variants. Concomitant use of HPLC and IEF can be used efficiently for presumed diagnosis of this rare variant. [ABSTRACT FROM AUTHOR]

This study was conducted to examine ability of the Capillarys 2 haemoglobin (Hb) testing system to assist in presumptive diagnosis of common Hb variants found in Southeast Asia including five α-chain and nine β-chain variants. Blood samples with unknown Hb variants sent from other hospitals to our centre for identification were re-analysed using the Capillarys 2 Hb analyser (SEBIA). DNA analyses by allele specific PCR assays were used to establish the final diagnoses. Five α-globin chain variants including Hbs Q-Thailand, Queens, Siam, Constant Spring and Paksé were detected. In heterozygous form, the machine demonstrated clearly two abnormal derivatives of Hbs A and A for the former three variants. Small peaks of Hb Constant Spring and Hb Paksé were observed but could not be differentiated. In contrast, only one abnormal peak of Hb A was observed for β-globin chain variants including those with more negative charge (Hb J-Bangkok, Hb Hope and Hb Pyrgos) and less negative charge (Hb D-Punjab, Hb S, Hb Korle-Bu and Hb C). Hb Tak, an elongated β-chain variant was co-separated with Hb F whereas the Hb Malay co-migrated with Hb A in a subject with high Hb Aβ- thalassaemia trait. The capillary electrophoresis system could clearly demonstrate the presence of abnormal Hbs and provide useful information for presumptive diagnoses in most cases. The Hb analysis results could help in selection of appropriate DNA testing for final diagnoses of these variants. [ABSTRACT FROM AUTHOR]

Hemoglobin variants are a result of genetic changes resulting in abnormal or dys-synchronous hemoglobin chain production (thalassemia) or the generation of hemoglobin chain variants such as hemoglobin S. Automated high-pressure liquid chromatography (HPLC) systems have become the method of choice for the evaluation of patients suspected with hemoglobinopathies. In this study, we evaluated the performance of two HPLC methods used in the detection of common hemoglobin variants: Variant and Ultra2. There were 377 samples tested, 26% (99/377) with HbS, 8.5% (32/377) with HbC, 20.7% (78/377) with other hemoglobin variant or thalassemia, and 2.9% with increased hemoglobin Ac. The interpretations of each chromatograph were compared. There were no differences noted for hemoglobins A, S, or C. There were significant differences between HPLC methods for hemoglobins F, A, and Ac. However, there was good concordance between normal and abnormal interpretations (97.9% and 96.2%, respectively). Both Variant and Ultra2 HPLC methods were able to detect most common hemoglobin variants. There was better discrimination for fast hemoglobins, between hemoglobins E and A, and between hemoglobins S and F using the Ultra2 HPLC method. [ABSTRACT FROM AUTHOR]

Hemoglobinopathies are common diseases in Mediterranean region of Turkey. In this study, the results of a 3-year premarital screening program are reported in Kahramanmaras province, which is located in East Mediterranean region. A total of 48,126 persons were screened in this program. Hematological analyses and electrophoresis were done to identify carriers. The prevalence of β-thalassemia trait and of sickle cell anemia trait, which were 2.1% and 0.5% in Turkey, were found to be 2.8% and 0.4%, respectively, in our study. Of the carriers of the β-thalassemia trait, 82% had high hemoglobin A2, 34% had high hemoglobin F, and 18% had both high hemoglobin F and hemoglobin A2. β-Thalassemia trait in Kahramanmaras is slightly higher than the average rate in Turkey. However, sickle cell anemia trait is similar to Turkey's averages. [ABSTRACT FROM AUTHOR]

Hemoglobinopathy (abnormal hemoglobin or hemoglobin variant) is an inherited disorder that results in the abnormal structure of globin chains of the hemoglobin (Hb) molecule. Many abnormal Hbs have been characterized worldwide, including more than 20 variants in Thailand. The Bio-Rad Variant II HPLC system is used for investigating hemoglobin variants at Songklanagarind Hospital. This system has been shown to be a sensitive, specific, and reproducible method, but some hemoglobin variants such as Hb Tak and Hb D-Punjab cannot, as yet, be clearly separated by this method. The aim of this study was to investigate the prevalence of hemoglobinopathy in southern Thailand using DNA sequencing and study the severity of each hemoglobin variant. A total of 58 hemoglobin variant samples were obtained from blood samples undergoing routine hemoglobin typing at Songklanagarind Hospital. Genomic DNAs were extracted from the samples, and the globin genes were analyzed by using PCR-direct sequencing. The molecular analysis revealed eight hemoglobin variants: 28 Hb C, 12 Hb D-Punjab, 7 Hb Tak, 4 Hb G-Makassar, 2 Hb Lepore-Hollandia, 2 Hb Q-Thailand, 2 Hb O-Indonesia, and 1 Hb Hope. The distribution of hemoglobin variants in southern Thailand is associated with geographic and/or ethnic backgrounds. This study may help hematologists understand better the prevalence of hemoglobin variants and their hematological features in this region. [ABSTRACT FROM AUTHOR]

In today's society, immigration and travel has resulted in large-scale population movements. This poses an additional challenge to the clinician when he or she takes the patient's history. The differential diagnosis of any presentation would need to include any diseases endemic to the area where the patient had been in. Ghana is considered a holoendemic high-risk area for the transmission of malaria. Moreover, compound heterozygous inheritance of hemoglobin (Hb) S and HbC often occurs in this area. We present a case of mixed Plasmodium falciparum–Plasmodium malariae infection complicating HbSC disease in a 34-year-old Ghanaian immigrant. We postulate that the malaria infection has transformed the patient's silent combined hemoglobinopathies (HbS/HbC) into a syndrome resembling a sickle cell crisis. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background A novel double heterozygosity for the α chain variant Hb Q India and β chain variant Hb S is described. Hb S is prevalent in the central part of India while Hb Q India in its heterozygous state is found mainly in Sindhi families. Methods Identification of both the variants, Hb S and Hb Q India, was done based on chromatograms of HPLC and capillary zone electrophoresis (CE). Confirmation of variants was done by PCR based amplification refractory mutation system (ARMS) technique. Results Both HPLC and CE confirmed the presence of Hb S. HPLC showed a pointed narrow peak of Hb Q India at retention time of 4.55 min while it is eluted in Hb D zone on CE. A hybrid variant of these α and β globin chains was eluted in Hb C window and Hb C zone on HPLC and CE respectively. Molecular studies using ARMS technique confirmed these findings. Both the cases showed positive sickling test and presented with mild anemia. Conclusion This is a unique 2 index cases for compound heterozygosity of Hb S with Hb Q India. [ABSTRACT FROM AUTHOR]

Haemoglobin H/Constant Spring is an important cause of severe haemoglobin H disease, but the Constant Spring protein is difficult to detect by electrophoresis. A technique for allele specific polymerase chain amplification of the 3'-end of the alpha 2 globin gene improved detection of the alpha cs alpha haemoglobin variant in DNA samples by slot-blot hybridisation. The alpha cs alpha mutation was confirmed in subjects that had been previously diagnosed by haemoglobin electrophoresis, and it was also detected in patients who were negative by protein electrophoresis. 10 of 103 unrelated Laotians with HbE were alpha cs alpha heterozygotes. Of these, 3 were negative to the normal probe because they had -alpha 3.7/alpha cs alpha with a single alpha globin deletion. 5 samples did not amplify or hybridise to either probe because they had deletions of both alpha 2 globin regions. The gene frequency for alpha cs alpha is about 0.05 for Laotians. This technique, which is highly specific and sensitive for rapid detection of the alpha cs alpha mutation, is suitable for clinical diagnoses and population studies. The true incidence of alpha cs alpha may prove to be greater than previously suspected from protein electrophoresis. [ABSTRACT FROM AUTHOR]

The Bio-Rad Variant Haemoglobin Testing System is an automated analyser which uses the principle of cation exchange high performance liquid chromatography. This evaluation was undertaken to examine the effectiveness of the instrument as a screening mechanism to assist in the diagnosis of haemoglobinopathies. The ability to quantify haemoglobins A2 and F and to ‘flag’ other haemoglobin variants was tested. Within-batch precision was excellent and between-batch precision was good. Linearity and sensitivity compared favourably with the manufacturer’s published ranges. The level of carry-over for haemoglobins F, S and A was less than 0.25%. The mean carry-over for haemoglobin A2 was 2.08%. This higher figure reflected the smaller absolute difference between the high and low samples for this parameter. The instrument never failed to indicate the presence of an abnormal haemoglobin in 271 selected samples. The instrument was reliable throughout the evaluation and at no time was a run aborted. [ABSTRACT FROM AUTHOR]

Linpisam S (Research Institute for Health Sciences, Chiang Mai University, Thailand), Tienboon P, Promtet N, Putsyalnunt P, Santawanpat and Fuchs G J. Iron deficiency and anaemia in children with a high prevalence of haemo-globinopathies: Implications for screening. International Journal of Epidemiology 1996, 25: 1262–1266.Background Haemoglobin (Hb) concentration is used as a sole test for iron deficiency anaemia (IDA) in most developing countries since most anaemia is believed to be due to iron deficiency and confirmatory testing is generally unavailable. Yet the validity of this approach in regions where haemoglobinopathies are endemic has not been documented. Methods Haemoglobin and serum ferritin (SF) were measured in 559 Northern Thai children aged 6 months to 13 years of age. The sensitivity of SF to identify iron deficiency was also assessed in a subsample of children with low or low normal Hb and normal SF by testing the Hb response to a trial of oral iron. Results While anaemia was common (27%), IDA constituted 19% and none of all anaemia in preschool and school age children, respectively (P < 0.002). Iron depletion was similarly more prevalent in younger children (P < 0.0002). Children with IDA were younger (P < 0.001) and the anaemia more severe (P < 0.0001) compared to those with non-IDA. Of anaemic children with normal SF values who received a therapeutic trial of iron, only 6% responded with an increase in Hb of ≥1g/dl. Conclusions For populations such as ours most anaemia is not due to iron deficiency and a single Hb determination is therefore not acceptable for a presumptive diagnosis of IDA. [ABSTRACT FROM PUBLISHER]

A letter to the editor is presented regarding the detection of Haemoglobin Kenitra through high-performance liquid chromatography (HPLC).

A letter to the editor is presented regarding the detection of Haemoglobin Kenitra through high-performance liquid chromatography (HPLC).

Hemoglobinopathies are highly prevalent in Indian population. DNA analysis to detect causative mutations is required for identifying rare hemoglobin variants or when hematological results are discordant with the clinical phenotype. In this report, we describe a novel hemoglobin variant caused by a mutation in beta-globin gene, Codon 7 GAG→CAG (Glu→Gln) that elutes in the position of sickle haemoglobin (HbS) in cation exchange high performance liquid chromatography. This report highlights possible diagnostic pitfalls in interpreting data solely based on haemoglobin analysis and usefulness of mutation screening in definitive diagnosis of hemoglobinopathies. [ABSTRACT FROM AUTHOR]

Patient: A 43-year-old African-American male. Chief Complaint: The patient sustained left upper arm pain after falling on his left elbow while moving furniture. He self-medicated with Tylenol, but pain increased in severity and was exacerbated by movement. Medical History: Significant for diabetes mellitus for the past 10-15 years and has been on oral hypoglycemic agents up to the time of the injury. He also had a history of facial cellulitis in 2005, a snake bite in 2001, and occasional acid reflux. There was no history of jaundice, pain crisis, or blood transfusions. Social History: The patient did not smoke or drink alcoholic beverages. He is a mechanic. Family History: Not available. Physical Examination: Was significant for the following: obese, alert, oriented to time, place, and person; heart: tachycardia without murmurs, gallops or rubs; lung and abdomen: unremarkable; extremity: erythematous, indurated, painful left upper extremity. Vital Signs: blood pressure: 134/82; pulse: 112/minute; respiratory rate: 20/minute; temperature: 101.3°F; pulse oximetry: 97%.Principal Laboratory Findings: Upon admission, laboratory tests were performed. Results are in Table 1. Additional Testing: The patient's peripheral blood smear showed hypochromia, microcytosis, and a few target cells. No sickle cells were identified. Because of the abnormal hemoglobin A1C result, high-performance liquid chromatography (HPLC) and hemoglobin electrophoresis were ordered (Figure 1 HPLC, Figure 2 alkaline electrophoresis, and Figure 3 acid electrophoresis). Serum iron performed after admission was 11 (31-144 ug/dL), bilirubin was 0.6 (0.2-1.2 mg/dL), and glycohemoglobin was 19.8 (<9%). A CT scan of the left upper extremity showed extensive fluid collection. He underwent exploration and debridement of the left upper arm and received intravenous antibiotics and insulin. Swelling gradually subsided, and he was discharged after 2 weeks of hospitalization. [ABSTRACT FROM AUTHOR]

The article assesses the predictive value of mean corpuscular volume (MCV) and mean corpuscular haemoglobin (MCH) contingent upon the facts that the measures form a common starting point in several suggested protocols for the screening of β-thalassaemia and heamoglobin A2 concentration is a reference standard measured on a continuous scale.

The article presents a case study of a 13-year-old Japanese girl with hemoglobin Seattle (Hb-Seattle), an inheritable hemoglobinopathy. Topics include low peripheral capillary oxygen saturation (SpO2), unstable Hb complex determined by positive isopropanol test, and quantification of fetal Hb (HbF).

A letter to the editor is presented in response to the article "Potential pithfalls in the diagnosis of Hb Handsworth in areas with high prevalence of Hb S.," by S. Zadjali and colleagues in the 2014 issue.

High performance liquid chromatography (HPLC) and electrophoresis are commonly used to diagnose various hemoglobinopathies. However, insufficient information about the transfusion history can lead to unexpected and confusing results. We are reporting a case of Juvenile myelomonocytic leukemia (JMML) in which HbHPLC was done to quantify fetal hemoglobin (HbF). The chromatogram showed elevated HbF along with a peak in the HbD window. A transfusion acquired peak was suspected based on the unexpectedly low percentage of HbD and was subsequently confirmed using parental HbHPLC. [ABSTRACT FROM AUTHOR]