Hemoglobin Variants Research Articles

Hemoglobin β-Globin Variants In Hispanic Patients: An Institutional Experience From Dallas, Texas

Hemoglobinopathies are the most common single-gene disorders in humans. There are 1,424 variants of human hemoglobin described with 951 involving the β-globin gene. Ancestry and geography play a significant role in the incidence and nature of hemoglobinopathies, with African, Asian, and Mediterranean populations and their descendants being amongst the most affected. Investigation of variants in individuals of Hispanic descent is needed to reflect the changing demographics of the United States. Hemoglobin β-globin evaluation through gel electrophoresis, high-performance liquid chromatography, and HBB gene sequencing was performed on patients from Texas hospitals between 2010 and 2015 and demographic parameters (age, sex, ethnicity) was subsequently analyzed. A total of 846 patients underwent hemoglobinopathy evaluation. A β chain variant was detected in 628 of the 846 total patients. Hispanic patients represented 37% (314/846 patients), which were equally distributed between females (50%; 156/314) and males (50%; 156/314). A β-globin chain variant was found in 67% of Hispanic patients with a distribution across 10 variants seen in greater than 1% of patients. For hemoglobin variants, an understanding of the regional and ethnic prevalence will improve patient care through more effective screening and identification of the variant, early diagnosis, and appropriate treatment if necessary, and better genetic counseling.

The pivotal role of HbA1c assay to detect hemoglobinopathies: A 5-year observational retrospective study in the population of Southern France.

Mobility and migration flows are growing from different countries of the world to European countries, including France and in particular the Mediterranean basin. This study aimed to investigate the presence of hemoglobin (Hb) variants in outpatients/inpatients of the Montpellier Hospital (France) in whom an HbA1c assay had been performed and for which the country of birth had been informed. This is a retrospective study from January 2016 to December 2020 based on all high-performance liquid chromatography (HPLC) chromatograms (Tosoh Bioscience HLC-723G8) having an alarm of suspected Hb variant during HbA1c measurement. The corresponding samples were systematically sent to the hematology laboratory for confirmation and identification of Hb variant. Patient's medical history, clinical and demographic data were extracted from each medical chart. Statistical analyses were performed using XLSTAT® software, version 2016.06.35661. Three hundred sixty-three patients were confirmed with Hb variant exhibiting 17 different Hb profiles, highlighting the pivotal role of glycated hemoglobin (HbA1c) as a detection step. The prevalence of Hb variant in this southern French population was 0.71%, with the highest frequency for the beta-globin variants (n = 342/363; i.e., 94.2%), including the most common: S, C, E, and D in 200/342 (58.5%), 83/342 (24.3%), 29/342 (8.5%), and 11/342 (3.2%), respectively. Among patients with Hb variants, almost half (165/363; i.e., 45.4%) were born in the African continent with a predominance for Morocco (32/165; i.e., 19.3%) and Algeria (29/165; i.e., 17.5%). HbA1c assay is a useful tool to detect Hb variants. Hemoglobinopathies are a public health issue in the current French population which is a multiethnic society. Despite the monocentric nature of our study, we note a high frequency of Hb variants in the south of France, which underlines the importance of screening for Hb variants in the whole population.

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

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

Rare mutations in the beta-globin gene and their clinical phenotypes

Objectives: Beta-thalassemia is one of the most common inherited genetic disorders and the repertoire of mutations in the beta-globin gene is ever-expanding. Sequencing for beta-globin gene mutations, is done, where phenotype-high-performance liquid chromatography discrepancies exist or where amplification refractory mutation system – polymerase chain reaction (ARMS-PCR) cannot identify common mutations, and often leads to the discovery of rare and novel mutations. Materials and Methods: This is a retrospective data analysis of 160 patients of beta-thalassemia and other hemoglobinopathies where some patients were found to have unexplained clinical features. Comprehensive genetic diagnosis was done on these patients by ARMS-PCR, gap-polymerase chain reaction, and sequencing. Results: Out of the total, 124 cases were homozygous/compound heterozygous for beta-thalassemia; 26 cases had heterozygous beta mutations with coexistent alpha-triplications and four patients (with unique clinical features) were found to harbor five rare mutations. The mutations detected were hemoglobin (Hb) Monroe (co-occurring with beta nt-42 mutation), beta-globin mutation −90(C>T), Hb Randwick, and Hb-M-Saskatoon (a variant hemoglobin causing methemoglobinemia and cyanosis). The spectrum of common mutations detected, in our study, was similar to that published in the literature. The unique clinical features of the patients were conclusively explained by the sequencing results. Conclusion: This study emphasizes the role of sequencing in the genetic diagnosis of beta-thalassemia. As next-generation sequencing increasingly finds use in routine diagnostics, newer clinically significant mutations will continue to be added to the large palette of mutations in beta-thalassemia.

Comparison of Third-Generation Sequencing and Routine Polymerase Chain Reaction in Genetic Analysis of Thalassemia.

Thalassemia is the most widely distributed monogenic autosomal recessive disorder in the world. Accurate genetic analysis of thalassemia is crucial for thalassemia prevention. To compare the clinical utility of a third-generation sequencing-based approach termed comprehensive analysis of thalassemia alleles with routine polymerase chain reaction (PCR) in genetic analysis of thalassemia and explore the molecular spectrum of thalassemia in Hunan Province. Subjects in Hunan Province were recruited, and hematologic testing was performed. Five hundred four subjects positive on hemoglobin testing were then used as the cohort, and third-generation sequencing and routine PCR were used for genetic analysis. Of the 504 subjects, 462 (91.67%) had the same results, whereas 42 (8.33%) exhibited discordant results between the 2 methods. Sanger sequencing and PCR testing confirmed the results of third-generation sequencing. In total, third-generation sequencing correctly detected 247 subjects with variants, whereas PCR identified 205, which showed an increase in detection of 20.49%. Moreover, α triplications were identified in 1.98% (10 of 504) hemoglobin testing-positive subjects in Hunan Province. Seven hemoglobin variants with potential pathogenicity were detected in 9 hemoglobin testing-positive subjects. Third-generation sequencing is a more comprehensive, reliable, and efficient approach for genetic analysis of thalassemia than PCR, and allowed for a characterization of the thalassemia spectrum in Hunan Province.

Poikilocytosis of Angora goats is associated with erythrocyte density and reticulocytosis.

Angora goats in South Africa experience several syndromes that result in notable morbidity and mortality in juveniles and adults, but not kids. Insight into their causes is hampered by the lack of normal reference values for this breed, and the present study therefore aimed to characterise (1) differences in the haematology of healthy kids at birth and weaning, and (2) the haematology of apparently healthy yearlings. Selected variables were measured by blood smear analysis, and complete blood counts were performed using an ADVIA 2120i. Variables at 1, 11, and 20 weeks of age were compared using the Friedman test and associations between variables of yearlings were determined by correlation analysis. In kids, red blood cell count, mean corpuscular haemoglobin concentration (MCHC), and poikilocytosis increased over time, while mean corpuscular haemoglobin (MCH) and mean corpuscular volume (MCV) decreased. Yearlings displayed a lower MCHC, and higher haemoglobin distribution width than previously reported for goats, and these were positively correlated with poikilocytosis, as were reticulocyte counts. White cell counts of yearlings exceeded normal values previously reported for goats, with some individuals displaying remarkably high mature neutrophil counts. Changes in haemoglobin variant expression or cation and water fluxes are possible explanations for the findings in kids, while in yearlings, the associations between MCHC, HDW, poikilocytosis, and reticulocytosis suggest alterations in red cell hydration in adulthood that are associated with increased red cell turnover. These findings may prove informative in the further investigation of various clinical syndromes in this population.

DETECTION OF HAEMOGLOBIN VARIANTS USING HIGH PERFORMANCE LIQUID CHROMATOGRAPHY IN A TERTIARY CARE HOSPITAL OF NORTHEAST INDIA.

Background: The most prevalent single gene disorders in India are hereditary haemoglobin (Hb) abnormalities. Because North East India lacks information on the pattern of hemoglobinopathies and thalassemias, it was thought beneficial to research these conditions using a series of patients sent to a clinical diagnostic laboratory. To study Aimthe spectrum of different haemoglobin variants in patients with Anaemia The study is carried out for Methods: a period of one year from July 2021 to June 2022. A total number of 90 cases of anemia were studied during this period. HPLC was done using BIORAD D-10 machine and the data were analysed. Of the 90 cases, 23 was diagnosed as HbE Results: Trait, 5 as HbE Disease, 8 as β- Thalassaemia Trait, 2 as Sickle Cell Trait, 1 each as HbE- β- Thalassaemia Trait and HbD Punjab, 33 as Iron Deficiency Anaemia and 17 as Anaemia of chronic disease. There is a female preponderance of the haemoglobin variants

Physio Biochemical Aspects of Sleeping Patterns in Relation to Plasma Glycated Haemoglobin Level in Type 2 Diabetic Patients

Introduction: Diabetes mellitus is a persistent metabolic condition distinguished by raised levels of glucose in the bloodstream, commonly referred to as hyperglycemia. This phenomenon arises due to insufficient endogenous insulin production or impaired insulin utilization by the body. Insulin is a hormone that is biosynthesized and secreted by the pancreatic gland, functioning to modulate the concentration of blood glucose in the body. Glycated hemoglobin, typically referred to as hemoglobin A1c or HbA1c, is a variant of hemoglobin that undergoes glycation upon prolonged exposure to elevated levels of glucose within the bloodstream. Hemoglobin is a crucial protein that is present within erythrocytes and is primarily responsible for the transportation of oxygen across the various tissues of the body. The assessment of HbA1c serves as a means of determining an individual's mean blood glucose levels during the preceding two to three months. The monitoring of long-term glycemic control in individuals with diabetes mellitus is widely recognized to be of utmost importance, with a valuable marker for this purpose being deemed necessary. The levels of HbA1c are commonly reported as a proportion of the total hemoglobin within the circulating blood in the form of a percentage. Objective: To compare the effects of sleeping patterns and plasma glycated haemoglobin levels in type 2 diabetic and non diabetic patients Study Design: Quantitative cross sectional Settings: Punjab Rangers Teaching Hospital, Lahore Duration: Four months i.e. 1st August 2022 to 31st December 2022 Data Collection Procedure: A pre validated questionnaire was used. Study was carried out at Punjab Rangers Teaching Hospital, Lahore. The total numbers of faculty members were 70 who participated after taking the informed consent. The study was done by simple random sampling technique. A fasting blood glucose analysis was conducted on all subjects through the collection of a 5cc blood sample. The study enrolled participants who were divided into two distinct groups based on their fasting blood glucose levels in which 35 were diabetic and 35 were controlled. Mean & standard deviation was calculated. P value is <0.005 means significant. Results: There were 70 participants in the study which equally divided into two groups i.e. thirty five each namely diabetic and controlled one. The participants in diabetic group include 18 males and 17 females while in control group 22 males and 13 females. After analyzing the data we came to know the statistical significant results were shown by insomnia severity index and HbA1c parameters as indicating major difference when compared both controlled and diabetic group in each parameter. Epworth sleepiness scale did not show any significant difference. Conclusion: It is concluded in this study that patients with poor diabetic control have less diabetic HbA1c control which increase higher levels of insomnia which clearly noted in the diabetic group when compared to control one. If we control the glycemic control of patients then definitely the level of insomnia decreases by providing the sleep comfort in daily life. Keywords: Diabetes mellitus, glycated haemoglobin, sleeping patterns, Type 2 diabetes, Insulin

Distribution pattern of haemoglobin variants, ABO and Rhesus blood groups among undergraduate students of EBSU, Abakaliki, Ebonyi State, southeast Nigeria

Distribution pattern of haemoglobin variants, ABO and Rhesus blood groups among undergraduate students of EBSU, Abakaliki, Ebonyi State, southeast Nigeria

Hemoglobin Variants in Patients With Microcytic Hypochromic Anemia: A Review of Indian Studies.

Microcytic hypochromic (MCHC) anemia with hemolytic components is common in clinical practice. Hemoglobinopathies and variants are one of the important underlying causes of MCHC anemia. The Indian population, by large, as various studies reported, showed a plethora of hemoglobinopathies with regional predilections for its types. The present systematic review is carried out for the evaluation of MCHC anemia for its underlying causes of hemoglobinopathies and their loco regional comparisons. The review was carried out by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method with selected keywords through the Google advanced search matchable to the objectives of the present systematic review. Upon the systematic review, it was observed that β thalassemia trait (βTT) remained the highest reported hemoglobinopathy. The other abnormal hemoglobin variants, though rare, also have been reported in the reviewed articles. It is concluded that patients with MCHCrefractory to its regular treatment should be subjected to high-performance liquid chromatography (HPLC) in exclusion of underlying hemoglobinopathy and abnormal hemoglobin variants.

Direct correction of haemoglobin E β-thalassaemia using base editors

Haemoglobin E (HbE) β-thalassaemia causes approximately 50% of all severe thalassaemia worldwide; equating to around 30,000 births per year. HbE β-thalassaemia is due to a point mutation in codon 26 of the human HBB gene on one allele (GAG; glutamatic acid → AAG; lysine, E26K), and any mutation causing severe β-thalassaemia on the other. When inherited together in compound heterozygosity these mutations can cause a severe thalassaemic phenotype. However, if only one allele is mutated individuals are carriers for the respective mutation and have an asymptomatic phenotype (β-thalassaemia trait). Here we describe a base editing strategy which corrects the HbE mutation either to wildtype (WT) or a normal variant haemoglobin (E26G) known as Hb Aubenas and thereby recreates the asymptomatic trait phenotype. We have achieved editing efficiencies in excess of 90% in primary human CD34 + cells. We demonstrate editing of long-term repopulating haematopoietic stem cells (LT-HSCs) using serial xenotransplantation in NSG mice. We have profiled the off-target effects using a combination of circularization for in vitro reporting of cleavage effects by sequencing (CIRCLE-seq) and deep targeted capture and have developed machine-learning based methods to predict functional effects of candidate off-target mutations.

Lipemia impact on HBA1C measurements in patients with and without hemoglobin variant: a rational laboratory use evaluation

This study aims to compare the HbA1c test results obtained by widely used methods using samples with various lipemia levels and Hb variants, and to determine whether it is possible to correct the lipemia effect in the identical samples. Out of the laboratory information system (LIS), 48 patients with various HbA1c results were identified including patients with and without Hb variants. After the baseline measurements, all samples were spiked with intralipid solution and treated by a subsequent 0.9% saline replacement procedure. HbA1c values were measured four times sequentially with enzymatic and capillary electrophoresis (CE) methods for each sample, and the measurements were categorized as follows: Baseline; Spiked, 5g/L; Spiked, 20g/L; Post-saline replacement. Sequential HbA1c measurements using the CE method did not show a significant difference, but samples containing 20 g/L triglycerides and samples treated with 0.9% saline replacement showed a significant difference when compared to baseline measurements in both patients with and without Hb variants using the enzymatic method (p < 0.001). The correlation between the two methods was strong at baseline measurements (r = 0.977), declined with lipemia (r = 0.968 and r = 0.737 for 5 g/L and 20 g/L triglycerides, respectively), and then increased with 0.9% saline replacement (r = 0.962) in patients without Hb variants. This study revealed that the enzymatic method, but not CE was susceptible to lipemia interference both in patients with and without Hb variants. Lipemia interference could be partially eliminated with 0.9% saline replacement, but enzymatic measurements were still somewhat affected.

JAK2 unmutated erythrocytosis: 2023 Update on diagnosis and management.

JAK2 unmutated or non-polycythemia vera (PV) erythrocytosis encompasses a heterogenous spectrum of hereditary and acquired entities. Foremost in the evaluation of erythrocytosis is the exclusion of PV through JAK2 (inclusive of exons 12-15) mutation screening. Initial assessment should also include gathering of previous records on hematocrit (Hct) and hemoglobin (Hgb) levels, in order to streamline the diagnostic process by first distinguishing longstanding from acquired erythrocytosis; subsequent subcategorization is facilitated by serum erythropoietin (Epo) measurement, germline mutation screening, and review of historical data, including comorbid conditions and medication list. Hereditary erythrocytosis constitutes the main culprit in the context of longstanding erythrocytosis, especially when associated with a positive family history. In this regard, a subnormal serum Epo level suggests EPO receptor mutation. Otherwise, considerations include those associated with decreased (high oxygen affinity Hgb variants, 2,3-bisphosphoglycerate deficiency, PIEZO1 mutations, methemoglobinemia) or normal oxygen tension at 50% Hgb saturation (P50). The latter include germline oxygen sensing pathway (HIF2A-PHD2-VHL) and other rare mutations. Acquired erythrocytosis commonly results from central (e.g., cardiopulmonary disease, high-altitude habitat) or peripheral (e.g., renal artery stenosis) hypoxia. Other noteworthy conditions associated with acquired erythrocytosis include Epo-producing tumors (e.g., renal cell carcinoma, cerebral hemangioblastoma) and drugs (e.g., testosterone, erythropoiesis stimulating agents, sodium-glucose cotransporter-2 inhibitors). Idiopathic erythrocytosis is an ill-defined terminology that presumes the existence of an increased Hgb/Hct level without an identifiable etiology. Such classification often lacks accounting for normal outliers and is marred by truncated diagnostic evaluation. Current consensus treatment guidelines are not supported by hard evidence and their value is further undermined by limited phenotypic characterization and unfounded concerns for thrombosis. We are of the opinion that cytoreductive therapy and indiscriminate use of phlebotomy should be avoided in the treatment of non-clonal erythrocytosis. However, it is reasonable to consider therapeutic phlebotomy if one were to demonstrate value in symptom control, with frequency determined by symptoms rather than Hct level. In addition, cardiovascular risk optimization and low dose aspirin is often advised. Advances in molecular hematology might result in better characterization of "idiopathic erythrocytosis" and expansion of the repertoire for germline mutations in hereditary erythrocytosis. Prospective controlled studies are needed to clarify potential pathology from JAK2 unmutated erythrocytosis, as well as to document the therapeutic value of phlebotomy.

SPECTRUM OF HEMOGLOBINOPATHIES AND THALASSEMIAS DIAGNOSED ON HPLC - A TERTIARY CARE HOSPITAL BASED STUDY

Background - The most common single gene disorders in the world are hemoglobinopathies and thalassaemias. The prevalence of thalassaemias and haemoglobinopathies varies by region. However, some communities have a very high incidence due to consanguinity, caste, and area endogamy, making this group of diseases a major public health problem in our country. High performance liquid chromatography (HPLC) is an automated instrument that is highly sensitive and specic, has a high resolution, and aids in the quantication of various haemoglobins. It is a viable alternative to electrophoresis. the study comp Materials and method - rises of total 220 patients presented with anaemia and were examined in the department of Medicine. Thereafter, blood smaples were taken and the hemoglobin typing were done in the department of Pathology by Cation exchange high performance liquid chromatography. - Among the 220 cases Results majority were females with 64.1% of cases and 35.9% (79) of cases are male. Out of total cases, 119 (54.1%) cases had normal hemoglobin and 101 (45.9%) cases had variant hemoglobin. Out 101 cases of variant hemoglobin, 38 (17.3%) cases were diagnosed with Hb E trait, 27 (12.3%) cases were detected with Hb E disease, 18 (8.2%) cases were diagnosed with Hb E-β Thalassemia, 17 (7.7%) cases were diagnosed as βThalassemia trait and 1 (0.5%) case was detected as β-Thalassemia major

5613396 DIFFERENCE IN HOSPITALIZATIONS AND ANNUAL BED DAYS FOR PATIENTS WITH SICKLE CELL DISEASE BY VARYING LEVELS OF ANEMIA: A RETROSPECTIVE ANALYSIS OF LINKED PRIMARY AND SECONDARY CARE DATABASES IN ENGLAND

Background: Sickle cell disease (SCD) is a life-threatening autosomal-recessive disorder in which the sickle variant of hemoglobin (Hb) polymerizes under deoxygenation, causing red blood cell sickling and hemolytic anemia. Anemia in SCD is associated with an increased risk of complications such as leg ulcers and end-organ damage (EOD), which often require hospitalization, a key driver of healthcare costs. Aims: To quantify differences in all-cause hospitalizations and annual bed days in patients with SCD and differing levels of anemia. Methods: We identified 6018 patients with SCD aged ≥12 years with ≥1 recorded Hb level between January 1, 2007, and March 31, 2019, from the Clinical Practice Research Datalink (Aurum version), an English longitudinal primary care electronic medical record, and linked these with Hospital Episode Statistics, a secondary care reimbursement data set. We obtained Hb levels from primary care records, when disease is expected to be relatively stable, as opposed to during hospitalization. We used Hb measurements separated by <30 days to calculate mean Hb for a time interval at a specific Hb level. Patients were grouped into Hb categories based on having ≥1 Hb record of <6 g/dL (severe anemia), 6 to <8 g/dL, 8 to 10.5 g/dL, or >10.5 g/dL; patient Hb category may have changed over the course of the study. Patient Hb intervals began with Hb in a category and ended on the day before a blood transfusion, with a Hb reading in a new category, or on the last activity date. We compared the significance of the categorical data distribution for hospitalizations using the Kruskal–Wallis test across Hb categories, extended with pairwise Wilcoxon rank sum testing. We repeated the above for hospitalizations due to any EOD and annual bed days. Results: Of 6018 patients with recorded Hb, 72% had a history of Hb >10.5 g/dL, 44% had 8 to 10.5 g/dL, 15% had 6 to 8 g/dL, and 3% had <6 g/dL. The annual rate of all-cause hospitalizations decreased as Hb increased: 5.84 in patients with Hb <6 g/dL, 4.13 for 6 to 8 g/dL, 3.3 for 8 to 10.5 g/dL, and 1.7 for >10.5 g/dL. Hospitalizations were significantly lower for patients with a history of Hb >10.5 g/dL than for those with Hb <6 g/dL (P<0.001); across Hb categories, the distribution of all-cause hospitalization was significant (P<0.001). Annual all-cause bed days decreased across increasing Hb categories, with a mean of 8.8 days in patients with a history of Hb <6 g/dL, 7.7 days with 6 to 8 g/dL, 5.8 days with 8 to 10.5 g/dL, and 3.2 days with >10.5 g/dL. A significant decrease in annual bed days was observed in patients with a history of Hb >10.5 g/dL compared with Hb <6 g/dL (P<0.001). Across Hb categories, the distribution of the difference in bed days was significant (P<0.001) (Figure).A total of 385 patients (6.4%) had ≥1 hospitalization for any EOD. Significantly fewer hospitalizations were attributable to any EOD in patients with a history of Hb >10.5 g/dL compared with those with a history of Hb <6 g/dL (0.36 and 2.4 hospitalizations per patient interval per year, respectively; P<0.001). Summary/Conclusion: All-cause hospitalizations and annual bed days were progressively reduced in patients with a history of higher Hb levels whereas patients with severe anemia did not experience the same benefit. Due to this tendency, appropriate measures should be taken to maximize Hb in patients with SCD. Reference 1. Kato GJ, Piel FB, Reid CD, et al. Sickle cell disease. Nat Rev Dis Primers. 2018;4:18010.

5613004 NEWBORN SCREENING FOR SICKLE CELL DISEASE IN GERMANY - THE FIRST YEAR

Newborn screening is the first and most important step in secondary prevention in children with sickle cell disease. Serious complications and deaths can be almost completely prevented by ensuring the necessary preventive measures against infection (vaccinations and penicillin prophylaxis) and with the help of training measures that enable parents to recognize the symptoms of acute anemia/hemolysis in good time. In 2017, as part of a consensus conference with over 50 participants from 13 nations, the requirements that a newborn screening program for sickle cell disease should meet were defined. In Germany, we have consistently implemented these requirements. In addition, a total of five pilot studies involving almost 220,000 participants were carried out. These studies have shown that if sickle cell disease were part of newborn screening, it would probably be one of the most prevalent target diseases. On the basis of the consensus document and the epidemiological data collected for the first time, the relevant institutions and authorities could ultimately be convinced of the usefulness of the screening. The amendment to the law required for the introduction of screening came into force on September 30, 2021. Since then, all children born in Germany have also been screened for sickle cell disease as part of the national newborn screening program. Due to the federal organization of the German state, there is still no official evaluation of the screening results. However, we conducted a survey among the eleven German screening laboratories and the 47 pediatric haematology centers that will take on the long-term care of the sick children. The data indicate that in the first year, approximately 120-150 of 800,000 newborns have sickle cell disease. The German authorities have approved HPLC, capillary electrophoresis and tandem mass spectrometry as measurement methods in screening. Deviating from this, some laboratories use molecular genetic methods to screen for the HbS mutation. In the laboratories participating in our survey, 13 false-positive findings were recorded during the survey period. 4 children had thalassemia major, which is not formally a target disease but is of course definitely worth reporting. Four children were HbS heterozygous. Three children had very rare hemoglobin variants and in three children we have no feedback on the false positive finding. We assume that the heterozygotes and the rare variants were reported out of uncertainty and fall under the “starting difficulties” category. These false positives all occurred within the first few weeks of the program and could be eliminated by retraining the laboratory staff. Conclusion: Not only, but also thanks to the constant support of our European colleagues, especially in the form of the 2017 consensus paper, we have succeeded in introducing newborn screening for sickle cell disease. The first preliminary data show that sickle cell disease, with a prevalence of 1:5000 - 1:6000, will be one of the top diagnoses in screening even in Germany.

A SILENT CASE OF SICKLE CELL DISEASE: A SERENDIPITOUS DISCOVERY

We present here a 4-year-old male child who came to hematology out-patient department for follow up for anemia which had required blood transfusion one and half year back. On clinical examination child was found to neither have pallor nor icterus. Blood was sent for complete hemogram. The hemogram showed a total hemoglobin of 8.4 gm%. Other RBC indices and WBC and platelet counts were within normal expectations. The reticulocyte count however was raised to 11%. Based on such a hemogram, on a high index of suspicion of a chronic hemolytic condition, despite clinical absence of any hemolytic features, a hemoglobin HPLC was performed in the Biochemistry laboratory. The HPLC revealed a percentage of HbS compatible with a HBS homozygous state. Based on this nding, the routine hemograms of both the parents were performed. These were found to be within normal limits. However, HPLC analyses for hemoglobin variants revealed HbS percentages compatible with HbS carrier i.e., heterozygous states. We thus provisionally concluded that this child was a case of Sickle cell homozygous, but atypical as because there was no history or clinical evidence of sickle cell disease symptomatology.

Biomarkers of oxidative stress and its nexus with haemoglobin variants and adverse foeto-maternal outcome among women with preeclampsia in a Ghanaian population: A multi-centre prospective study.

Haemoglobin variants and preeclampsia (PE) are associated with adverse fatal events of which oxidative stress may be an underlying factor. Oxidative stress (OS) among preeclamptic women with haemoglobin variants has been well established. It is, however, unclear whether haemoglobin variants induce OS to aggravate the risk of adverse foeto-maternal outcomes in pregnant women with preeclampsia. We measured the levels of OS biomarkers and determined the association between haemoglobin variants, and adverse foeto-maternal outcomes among pregnant women with PE. This multi-centre prospective study recruited 150 PE women from three major health facilities in both Bono and Bono east regions of Ghana from April to December 2019. Haemoglobin variants; HbAS, HbSS, HbSC, HbCC, and HbAC were determined by haemoglobin electrophoresis. OS biomarkers such as malondialdehyde (MDA), catalase (CAT), vitamin C, and uric acid (UA) along with haematological and biochemical parameters were estimated using standard protocol. Adverse pregnancy complications (APCs) such as post-partum haemorrhage (PPH), HELLP (Haemolysis, Elevated liver enzymes, Low platelet count) syndrome, preterm delivery, neonatal intensive care unit (NICU) admission, and neonatal jaundice were recorded. Of the 150 pregnant women with preeclampsia, the distribution of haemoglobin AA, AS, AC, CC, SS and SC phenotypes were 66.0%, 13.3%, 12.7%, 3.3%, 3.3% and 1.3%, respectively. The most prevalent foeto-maternal outcomes among PE women were NICU admission (32.0%) followed by PPH (24.0%), preterm delivery (21.3%), HELLP syndrome (18.7%), and neonatal jaundice (18.0%). Except for vitamin C level which was significantly higher in patients with at least a copy of Haemoglobin S variant than those with at least a copy of Haemoglobin C variant (5.52 vs 4.55; p = 0.014), levels of MDA, CAT, and UA were not statistically significantly different across the various haemoglobin variants. Multivariate logistic regression model showed that participants with HbAS, HbAC, having at least a copy of S or C and participants with HbCC, SC, SS had significantly higher odds of neonatal jaundice, NICU admission, PPH and HELLP syndrome compared to participants with HbAA. Reduced levels of vitamin C are common among preeclamptics with at least one copy of the HbC variant. Haemoglobin variants in preeclampsia contribute to adverse foeto-maternal outcomes with Haemoglobin S variants being the most influencing factor for PPH, HELLP, preterm labour, NICU admission, and neonatal jaundice.

Distribution characteristics and clinical phenotype analyses of hemoglobin variants in the Z region of Central Guangxi, Southern China

ABSTRACTObjectiveTo investigate the molecular diagnosis of hemoglobin variants in Z region by Capillary electrophoresis in Central Guangxi, Southern China, and analyze their distribution and phenotypic characteristics, to provide a reference for clinical consultation and prenatal diagnosis for couples.MethodsA total of 23,709 subjects were collected for blood routine analysis, hemoglobin analysis, and common α- and β-globin gene loci in Chinese population. The hemoglobin electrophoresis components were divided into Zone 1-Zone 15 (Z1-Z15) by Capillary zone electrophoresis (CE). For samples not clearly detected by the conventional technology, Sanger sequencing, and multiplex ligation-dependent probe amplification (MLPA) were used. Single-molecule real-time (SMRT) sequencing technology was used to analyze rare-type genes in a sample with a structural variation.ResultsTen rare hemoglobin variants distributed in Z region were detected in 23,709 samples, including Hb Cibeles, which was reported for the first time in Asia; Hb J-Broussais, Hb G-Honolulu and J-Wenchang-Wuming, they were first reported in Guangxi; 1 case of Hb Anti-Lepore Liuzhou, which was a newly discovered hemoglobin variant; hemoglobin variants Hb G-Siriraj, Hb Handsworth, Hb Q-Thailand, Hb Ube-2, Hb NewYork were also detected.ConclusionThere are a few studies on rare hemoglobin variants in Z region in Southern China. Ten rare hemoglobin variants were found in this study. The hematological phenotype and component content of hemoglobin variants are related to the occurrence of thalassemia. This study enriched the data of rare hemoglobin variants in Southern China and provided a comprehensive data basis for prenatal diagnosis of hemoglobin variants in this area.

Heart Disease Screening and False Hypoxemia in the Neonate

Background Screening for congenital heart diseases by pulse oximetry is used for the initial assessment of the neonate. Variants of hemoglobin F can compromise light absorbance, inducing erroneous results. Case report Two infants screened for congenital heart disease showed an asymptomatic low peripheral oxygen saturation. Arterial blood gases analysis revealed a normal arterial pressure of oxygen and oxygen saturation. More likely and/or severe causes of hypoxemia were ruled out. This “artifact” with SpO2-SaO2 dissociation, and after exclusion of other common etiologies of hypoxemia, raised the clinical suspicion of hemoglobinopathy. Hemoglobin molecular and genetic studies identified specific mutations in gamma chains from hemoglobin F, named hemoglobin F Sardinia. Conclusion Hemoglobin F variants may result in low peripheral oxygen saturation readings by pulse oximetry, explaining the discordance in the clinical appearance and low peripheral oxygen saturation readings.