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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]

Haemoglobinopathies constitute a large proportion of hemolytic anemias constituting around 74% of hereditary hemolytic anemias. Till date, about 200 alpha chain variants have been identified, one of which is Hb Fontainebleau. It is a rare alpha chain variant characterized by an Alanine → Proline substitution at codon 21 with a GCT>CCT change at the molecular level. It is incidentally detected on HPLC as an unknown peak. We present a case of Hb Fontainebleau in a 53-year-old male patient who presented with symptoms related to hemolytic anemia and an unknown peak on the HPLC chromatogram. [ABSTRACT FROM AUTHOR]

Hemoglobin disorders are among the most common genetic diseases worldwide. Molecular diagnosis is helpful in cases where the diagnosis is uncertain and for genetic counseling. Protein‐based diagnostic techniques are frequently adequate for initial diagnosis. Molecular genetic testing is pursued in some cases, particularly when a definitive diagnosis is not possible and especially for the purpose of assessing genetic risk for couples wanting to have children. The expertise available in the clinical hematology laboratory is essential for the diagnosis of patients with hemoglobin abnormalities. Initial diagnoses are made using protein‐based techniques such as electrophoresis and chromatography. Based on these findings, genetic risk to an individual's offspring can be assessed. In the setting of β‐thalassemia and other β‐globin disorders, coincident α‐thalassemia may be difficult to diagnose, which can have potentially serious consequences. In addition, unusual forms of β‐thalassemia caused by deletions in the β‐globin locus cannot be definitively characterized using standard techniques. Molecular diagnostic testing has an important role in the diagnosis of hemoglobin disorders and is important in the setting of genetic counseling. Molecular testing also has a role in prenatal diagnosis to identify fetuses affected by severe hemoglobinopathies and thalassemias. [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]

Key Content: The haemoglobinopathies encompass a complex collection of red blood cell disorders that are responsible for considerable morbidity and mortality in women and their unborn children.Sickle cell disease and the thalassaemias are the commonest haemoglobinopathies encountered in UK clinical practice.A consistent standard of care will enable women with haemoglobinopathies to have a pregnancy that is as safe as possible, with good outcomes and minimal long‐term effects on their health and the health of their babies.The most effective way to deliver a consistent standard of care for these women is via the multidisciplinary team (MDT). The MDT should include a haematologist, cardiologist, maternal medicine obstetrician, specialist midwife, reproductive medicine specialist and a nurse specialist.The care of these women, within the MDT, should start with pre‐conception advice and continue through their antenatal care, intrapartum support and finally, provide postnatal considerations including contraception advice. Learning Objectives: To understand the inheritance, incidence, detection and pathophysiology of the commonest haemoglobinopathies.To appreciate the role of pre‐conception advice and prenatal diagnosis in the management of women with a haemoglobinopathy.To appreciate the multidisciplinary team approach in managing women with these conditions. Ethical Issues: Prenatal diagnostic techniques can be used to diagnose an affected pregnancy; however, diagnosis after conception means families must address the option of terminating the pregnancy. This requires expert counselling to minimise long‐term sequelae.The definitive prenatal tests – chorionic villus sampling and amniocentesis – are both associated with a small risk of miscarriage.Non‐invasive free fetal DNA (ffDNA) tests that will minimise the risk of testing to the developing fetus are being developed, but use of these tests will still require expert counselling both before and after a test is taken. [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]

Objectives: HBB-related significant hemoglobinopathies have been anecdotally associated with low fetal fraction on noninvasive prenatal screening (NIPS). We sought to compare the difference in fetal fraction using NIPS in women with HBB-related significant hemoglobinopathies (HSH) and women with normal hemoglobin.Study Design: This is a retrospective case-control study. Cases were women with a diagnosis of HSH using NIPS from a commercial laboratory. The comparison group was women with hemoglobin AA from a tertiary care center database. We tested for differences in median fetal fraction using quantile regression analysis, adjusting for maternal body weight and gestational age.Results: This study includes 35 women with clinically significant HSH and a comparison group of 636 women with hemoglobin AA. Adjusting for gestational age and body weight, the median fetal fraction was 4.1 point lower in the HSH than in the comparison group (β - 4.1; 95% -5.7 to -2.5, p < .05). The rate of no-calls due to low fetal fraction was significantly higher in the clinically significant HSH group than in the comparison group [HSH: n = 9/35, 25.7% versus comparison: n = 32/636, 5.0% (p < .001)].Conclusion: Women with HSH were more likely to have a lower fetal fraction and ultimately a five-fold higher no-call rate. What's already known about this topic?Low fetal fraction is one of the most common causes of no-call result in noninvasive prenatal screeningHigh maternal weight, early gestational age and fetal aneuploidies are associated with low fetal fraction What does this study add?HBB-related significant hemoglobinopathies are associated with low fetal fractionReduction in fetal fraction due to HBB-related significant hemoglobinopathies may also result in higher no-call rate. [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]