Hemoglobin e syndromes: emerging diagnostic challenge in north India

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.

Red blood cell indices in different hemoglobinopathies: A cross-sectional study in Eastern India

Introduction

Beta thalassemia and hemoglobin (HbE)-related hemoglobinopathies are common public health problems in developing countries. High-performance liquid chromatography (HPLC) is currently the diagnostic test of choice for carrier detection, but it is costly. Hence, some initial screening and complementary tests are required, which can be affordable.

Aims

To find out the distribution of different red blood cell (RBC) indices in beta thalassemia trait (BTT) and HbE-related hemoglobinopathies and to determine their significance as screening tests to distinguish between these hemoglobinopathies.

Study Settings and Design

This observational cross-sectional study has been carried out at an NABL (National Accreditation Board for Testing and Calibration Laboratories)-accredited Laboratory of Eastern India with approval from the concerned Institutional Ethics Committee from January 2021 to March 2021.

Methods and Material

: HPLC tests and complete hemograms were performed on 2247 ethylenediaminetetraacetic acid anti-coagulated blood samples over 3 months. Patients <1 year of age or having a history of blood transfusion within the past 06 months were excluded.

Statistical Analysis

: One-way analysis of variance along with Bonferroni post-hoc test was performed to find out significant differences of means of mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), hemoglobin%, red blood cell (RBC) count, and red cell distribution width (RDW-CV) among concerned hemoglobinopathies.

Results

The results show a significant difference of total RBC count, RDW, MCV, MCH, and MCHC between BTT and E-trait. No significant difference of mean was found between HbE homozygous and E-beta. E-trait differs from both HbE homozygous and E-beta significantly in three parameters, namely, RDW, MCV and MCH. A value of MCV at ≤73.8 fl and MCH at ≤21.9 pg may be a clue of diagnosis for BTT rather than E-trait with >90% sensitivity and >80% specificity.

Conclusion

RBC indices vary significantly between BTT and other HbE-related hemoglobinopathies. They can specially be utilized to differentiate BTT and E-trait as supportive tests in addition to the gold standard test of HPLC.

Phenotypic Diversity and Clinico-Hematological Profile of Hb E-Beta Thalassemic Children

Hb E-Beta thalassemia is a disease with marked clinical diversity. In this study, phenotypic diversity of Hb E-β thalassemia children were analysed by studying the clinical and hematological parameters. This was a cross sectional study done in one and a half year period in the department of Pediatrics of a tertiary care teaching hospital. Participants were 62 Hb E-β thalassemic children of age group 1 month to 18 years coming to the Thalassemia day care centre for blood transfusion. Data collected from history, examination findings and investigation reports were analyzed. M:F ratio was 1.07:1; 71% children were above 5 years of age. 90.3% children were Hindu. In 66.1% children, Hb level was below 5 gm/dl at the time of diagnosis. Mean HbF level was 32.6% ± 11.2. Stunting was seen in 64.5%. Average liver and spleen size were 2.5 and 4.4 cm respectively. Beside pallor, most common clinical findings were splenomegaly (93.5%), facial deformity (87%), dusky skin color (82.5%) and hepatomegaly (75.8%). 1.6% children were mild, 43.5% children were moderate and 54.8% children were of severe type. In our study there was no significant correlation between severity of the disease and HbF level (r = 0.0853, p = 0.0509). Age at the time of diagnosis, hemoglobin level at the time of first transfusion, age at receiving first blood transfusion, requirement of blood transfusion, spleen size and growth, are some factors affecting severity of the disease. But severity cannot be assessed by considering only one clinical or hematological parameter but by considering several parameters together.