Clinico-hematological parameters of sickle hemoglobin hemoglobinopathies and its correlation with ethnicity: A study from Northern Districts of West Bengal

Background: Inherited disorders of blood include thalassemias and hemoglobinopathies which are one of the major public problems in India. In sickle hemoglobin (HbS) hemoglobinopathies, production of abnormal sickle-shaped red cells results in variable degree of hemolytic anemia along with acute and chronic tissue damage due to vaso-occlusion. The term sickle cell anemia is reserved for homozygous state (SS) for sickle cell gene, while the heterozygous sickle cell trait (AS) has never been considered a disease, has one abnormal gene. Aims: The present study was undertaken to determine the occurrence of HbS hemoglobinopathies in Northern districts of West Bengal and its correlation with ethnicity and different hematological parameters. Methods: A hospital based cross-sectional study was carried out in the Department of Pathology, North Bengal Medical College , along with its thalassemia control unit, over a period of 5 years. Various hematological parameters (Hb, packed cell volume, mean corpuscular volume [MCV], mean corpuscular hemoglobin [MCH], MCH concentration [MCHC], red cell distribution width) were calculated, and hemoglobin variants were determined by high-performance liquid chromatography. Results: 908 (2.19%) patients of sickle cell disease SCD were diagnosed, among a total of 41,549 cases studied. The distribution of HbS hemoglobinopathies were SS-51 (5.6%), AS-727 (80.1%), HbS/beta thalassaemia-109 (12.0%), compound heterozygisity for HbS/Hb E hemoglobinopathy 10 (1.1%) cases. The study revealed that 769 (84.7%) of such HbS variants occurred among the tribal population. Low values of MCV, MCH, and MCHC were noted in both sickle cell trait and in HbS/beta-thalassemia. Conclusion: There is a high occurrence of sickle cell disease in the socioeconomically backward population groups. Mass screening is required in this region for the assessment of different hemoglobin variants among the diverse ethical groups.