Potential Pithfalls in Using HPLC and its Interpretation in Diagnosing HbS

Abstract

Hemoglobinopathies are the most common group of autosomal recessive monogenic disorders worldwide. They include both thalassemias and structural hemoglobin variants. More than 1,100 hemoglobin variants have been detected so far out which majority of them are new variants while some others are very commonly found in some populations 1, 2,3. Sickle hemoglobin (Hb S) is a very common structural variant found worldwide. Sickle cell disorder is a group of hereditary blood disorders caused due to a mutation in the β globin gene resulting in the production of abnormal hemoglobin called sickle hemoglobin (Hb S). Hb S is so called because the abnormal hemoglobin causes the red blood cells to become rigid and sickle shaped which blocks blood flow and breaks down easily4. Severity in sickle cell disorders varies and the symptoms range from anemia to vaso-occlusive crises which over a period of time affect multiple organs with chronic deterioration over the time5. When the sickle mutation is inherited with any other globin gene mutation it is called variant sickle cell syndromes and the clinical severity may differ when compared to homozygous sickle mutation6. Early detection of sickle cell disease (SCD) helps in the prophylactic therapy7 and proper management of the disease5. This is the reason why new born or neonatal screening programs for sickle cell disorders have been initiated in many countries where the prevalence of sickle cell anemia is very high8,9 .Therefore it becomes all the more important that extreme precaution has to be taken while diagnosing sickle cell disease as it provides a direction for life long treatment and prophylaxis of the patient along with counselling of the parents for prenatal diagnosis or pre implantation genetic diagnosis in future pregnancies3,10. Bone marrow transplant with HLA identical donors and use of hydroxyurea may be beneficial to reduce frequency of crises and reduce tissue damage11.