PREVALENCE AND HEMATOLOGICAL PROFILE OF HEMOGLOBIN D TRAIT AND ITS DIFFERENTIATION FROM Β-THALASSEMIA TRAIT USING HPLC: A RETROSPECTIVE STUDY

Abstract

Background: Hemoglobin D (Hb D) is a clinically silent mutation in beta chain of hemoglobin which often remains undiagnosed without proper screening, therefore leading to complications such as anemia, adverse pregnancy outcomes, and risk of transmission to offspring.

Objective: This study aimed to evaluate the prevalence and hematological parameters of hemoglobin D to aid in differentiating this mutant hemoglobin from normal individuals and individuals of beta thalassemia trait on clinical basis

Methods: A cross-sectional retrospective study was conducted using patient records from the central laboratory of Dr. Ruth K. M. Pfau Civil Hospital. Data was collected from High-Performance Liquid Chromatography (HPLC) and Complete Blood Count (CBC) tests. A total of 911 patients were included in the study. SPSS version 25 was used for statistical analysis.

Results: Out of 911 patients, 13 individuals were found to have HbD trait. The findings indicate that mean MCV, MCH and MCHC of the patients with hemoglobin D 72.915±13.4 fL, 21.692±4.8 pg/cell and 29.123±3.2 g/dL, respectively, highlighting mildly reduced MCH and MCHC values, indicating mild hypochromia. Moreover, HPLC results of Hb D individuals revealed significant elevation of Hb F (P=0.022) and a mild decrease in Hb A levels (51.1600%±1.81) as compared to normal individuals (88.1716% ±43.8), approaching statistical significance (P=0.060). However, distinguishing HbD from beta thalassemia is also challenging for clinicians as both present with mild microcytic hypochromic anemia. A key finding of our study indicates normal Hb A2 levels (2.150%±0.49) in patients with HbD, whereas elevated Hb A2 levels (mean 4.371%±0.5) in patients with beta thalassemia trait. This confirms Hb A2 as the most reliable biochemical marker for differentiating Hb D from BTT.

Conclusion: This study highlights the importance of HPLC or hemoglobin electrophoresis for correct diagnosis of Hb D. The significant elevation in Hb F and the presence of a Hb D band in HPLC are key biochemical markers that differentiate these carriers from normal individuals. Routine screening, accurate diagnosis via HPLC, and comprehensive genetic counseling are essential strategies for preventing transmission, improving patient outcomes and ultimately reducing the burden of major hemoglobin disorders in the population