Diagnosis of common hemoglobinopathies among South East Asian population using capillary isoelectric focusing system

Microstrip isoelectric focusing with deep learning for simultaneous screening of diabetes, anemia, and thalassemia

BACKGROUND

Hemoglobin (Hb) is an important protein in red blood cells and a crucial diagnostic indicator of diseases, e.g., diabetes, thalassemia, and anemia. However, there is a rare report on methods for the simultaneous screening of diabetes, anemia, and thalassemia. Isoelectric focusing (IEF) is a common separative tool for the separation and analysis of Hb. However, the current analysis of IEF images is time-consuming and cannot be used for simultaneous screening. Therefore, an artificial intelligence (AI) of IEF image recognition is desirable for accurate, sensitive, and low-cost screening.

RESULTS

Herein, we proposed a novel comprehensive method based on microstrip isoelectric focusing (mIEF) for detecting the relative content of Hb species. There was a good coincidence between the quantitation of Hb via a conventional automated hematology analyzer and the one via mIEF with R2 = 0.9898. Nevertheless, our results showed that the accuracy of disease diagnosis based on the quantification of Hb species alone is as low as 69.33 %, especially for the simultaneous screening of multiple diseases of diabetes, anemia, alpha-thalassemia, and beta-thalassemia. Therefore, we introduced a ResNet1D-based diagnosis model for the improvement of screening accuracy of multiple diseases. The results showed that the proposed model could achieve a high accuracy of more than 90 % and a good sensitivity of more than 96 % for each disease, indicating the overwhelming advantage of the mIEF method combined with deep learning in contrast to the pure mIEF method.

SIGNIFICANCE

Overall, the presented method of mIEF with deep learning enabled, for the first time, the absolute quantitative detection of Hb, relative quantitation of Hb species, and simultaneous screening of diabetes, anemia, alpha-thalassemia, and beta-thalassemia. The AI-based diagnosis assistant system combined with mIEF, we believe, will help doctors and specialists perform fast and precise disease screening in the future.

Diagnosis and screening of abnormal hemoglobins

Hemoglobin (Hb) abnormalities, such as thalassemia and structural Hb variants, are among the most prevalent inherited diseases and are associated with significant mortality and morbidity worldwide. However, there were not comprehensive reviews focusing on different clinical analytical techniques, research methods and artificial intelligence (AI) used in clinical screening and research on hemoglobinopathies. Hence the review offers a comprehensive summary of recent advancements and breakthroughs in the detection of aberrant Hbs, research methods and AI uses as well as the present restrictions anddifficulties in hemoglobinopathies. Recent advances in cation exchange high performance liquid chromatography (HPLC), capillary zone electrophoresis (CZE), isoelectric focusing (IEF), flow cytometry, mass spectrometry (MS) and polymerase chain reaction (PCR) etc have allowed for the definitive detection by using advanced AIand portable point of care tests (POCT) integrating with smartphone microscopic classification, machine learning (ML) model, complete blood counts (CBC), imaging-based method, speedy immunoassay, and electrochemical-, microfluidic- and sensing-related platforms. In addition, to confirm and validate unidentified and novel Hbs, highly specialized genetic based techniques like PCR, reverse transcribed (RT)-PCR, DNA microarray, sequencing of genomic DNA, and sequencing of RT-PCR amplified globin cDNA of the gene of interest have been used. Hence, adequate utilization and improvement of available diagnostic and screening technologies are important for the control and management of hemoglobinopathies.

An efficient isoelectric focusing of microcolumn array chip for screening of adult Beta-Thalassemia

Traditional capillary isoelectric focusing (cIEF), liquid chromatography (LC) and capillary zone electrophoresis (CZE) still suffered from low resolution for hemoglobinopathy screening. Herein, a 30-mm pH 5.2-7.8 microcolumn IEF (mIEF) array chip was developed for hemoglobinopathy screening. As a proof of concept, adult beta-thalassemia was chosen as a model disease. In the method, blood samples were hemolyzed via hemolysin solution and loaded into the microcolumn. The experiments showed that (i) the species of Hb A, F, A₂ and variants were clearly separated in the chip, and the resolution was greatly higher than the ones of LC/CZE/cIEF; (ii) up to 24 samples could be simultaneously analyzed in 12-min run; (iii) the intraday and interday RSDs were respectively 3.32-4.91 % and 4.07-5.33 %. The assays of mIEF to total 634 samples were compared with the ones of LC (n = 327) and PCR (n = 307). The cutoff of 3.5 % HbA₂ led to the sensitivity of 100 % and specificity of 89.1 % for the mIEF-based screening; and there was 96.7 % coincidence between the methods of mIEF and PCR if refer Hb A₂ and F. The method had the merits of facility, efficiency, specificity and sensitivity in contrast to the currently-used methods, implying its potential to screening of beta-thalassemia and hemoglobinopathies.

Hb Huadu [α124(H7)Ser→Thr (TCC>ACC), HBA2: c.373T>A]: A Novel Variant of the α-Globin Gene

Here, we report a novel α chain hemoglobin (Hb) variant found during routine thalassemia screening. This Hb variant can be detected by capillary electrophoresis (CE) but cannot be recognized by high performance liquid chromatography (HPLC). Sanger sequencing revealed a heterozygous missense substitution at nucleotide 373 on the HBA2 gene, which results in the replacement of serine by threonine at codon 124 [α124(H7)Ser→Thr (TCC>ACC), HBA2: c.373T>A]. It is the first report of this variant, named Hb Huadu for the birthplace of the proband. In addition, the proband coinherited the heterozygous codons 41/42 (-TTCT) (HBB: c126_129delCTTT) on the β-globin gene.

Advances in screening of thalassaemia

Thalassaemia is a common hereditary haemolytic anaemia. Mild cases of this disease may be asymptomatic, while patients with severe thalassaemias require high-dose blood transfusions and regular iron removal to maintain life or haematopoietic stem cell transplantation to be cured, imposing an enormous familial and social burden. Therefore, early, timely, and accurate screening of patients is of great importance. In recent years, with the continuous development of thalassaemia screening technologies, the accuracy of thalassaemia screening has also improved significantly. This article reviews the current research on thalassaemia screening.

Evaluation of the Significance of Tear Ferning Patterns in beta-Thalassemia Patients

AIM

This study was designed to evaluate the tear film in beta-thalassemia patients using tear ferning (TF) and phenol red thread (PRT) tests.

METHODS

Forty beta-thalassemia patients, aged 18 - 38 years (25.7 ± 6.0 years), along with a control group of 40 age-matched subjects with healthy eyes completed the study. All subjects completed the ocular surface disease index (OSDI) first, followed by the TF and PRT tests with a 5-minute gap between the tests.

RESULTS

Significant differences (Wilcoxon test, p < 0.05) were observed between the beta-thalassemia and control groups in all scores. Among beta-thalassemia patients, OSDI scores indicated eye dryness in 35 subjects (87.5%). PRT showed dryness in 31 subjects (77.5%) in the right and left eyes, and the TF grades were ≥ 2 for the tears collected from 35 subjects (87.5%). There was a strong correlation (r = 0.851, p = 0.001) between the PRT measurements in the right and left eyes. There was a medium correlation between OSDI and TF scores (r = 0.309, p = 0.026) and between OSDI and age (r = 0.365, p = 0.010). Age had a moderate negative correlation (r = - 0.328, p = 0.019) with the PRT obtained from the right eye.

CONCLUSION

Significant ocular dryness symptom was observed in beta-thalassemia patients, based on the scores collected from TF and PRT tests. Beta-thalassemia patients develop dry eyes, possibly due to several factors, including reduced tear secretion. Therefore, it is important to regularly evaluate both the quality and quantity of tears in patients with beta-thalassemia.

Alpha-Thalassemia in North Morocco: Prevalence and Molecular Spectrum

Unlike the other hemoglobinopathies, few researches have been published concerning α-thalassemia in Morocco. The epidemiological features and the mutation spectrum of this disease are still unknown. This regional newborn screening is the first to study α-thalassemia in the north of Morocco. During the period from January 2015 to December 2016, 1658 newborns umbilical blood samples were investigated. Suspected newborns were screened for α-globin defects using Gap-PCR and Multiplex Ligation-dependent Probe Amplification technique. The prevalence of α-thalassemia, its mutation spectrum, and its allelic frequencies were described for the first time in Morocco. Six different α-globin genetic disorders were detected in 16 neonates. This screening valued the prevalence of α-thalassemia in the studied population at 0.96% and showed the wide mutation spectrum and the heterogeneous geographical distribution of the disease. A high rate of carriers was observed in Laouamra, a rural commune in Larache province. Heterogeneity of α-globin alleles in Morocco explains the high variability of α-thalassemia severity. This diversity reflects the anthropological history of the country. These results would contribute to the prevention of thalassemia in Morocco directing the design of a nationwide screening strategy and awareness campaign.

Recent advances in CE and microchip-CE in clinical applications: 2014 to mid-2017

CE and microchip CE (ME) are powerful tools for the analysis of a number of different analytes and have been applied to a variety of clinical fields and human samples. This review will present an overview of the most recent applications of these techniques to different areas of clinical medicine during the period of 2014 to mid-2017. CE and ME have been applied to clinical chemistry, drug detection and monitoring, hematology, infectious diseases, oncology, endocrinology, neonatology, nephrology, and genetic screening. Samples examined range from serum, plasma, and urine to lest utilized materials such as tears, cerebral spinal fluid, sweat, saliva, condensed breath, single cells, and biopsy tissue. Examples of clinical applications will be given along with the various detection systems employed.

Co-inheritance of α0 -thalassemia elevates Hb A2 level in homozygous Hb E: Diagnostic implications

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.