Background- Thalassemia is among the most common genetic disorders worldwide. They are a group of autosomal disorders where there is an inhibition of the production of α or β globin chains of hemoglobin resulting in varying level of anemia. Objectives- 1) To study the diagnostic predictibilty of CBC and various indices in identifying β-thalassaemia trait (β-TT) in pregnant females. 2) For prevention of β-thalassaemia major (β-TM) by genetic counseling.
Material and Methods - 400 patients having microcytic hypochromic anemia were analysed for Hb, RBC, MCV, MCH, MCHC, TLC, platelet count; and various indices including Mentzer index, England and Fraser index, RBC count and Green and King formula. The blood samples from patients with possibility of β-TT were used for HbA2 estimation by high performance liquid chromatography (HPLC) for confirmation.
Results - Out of 400 cases of microcytosis, 40 were confirmed to have β-TT and 2 cases of sickle cell trait by HPLC. In our study the incidence of β-TT was 10% in the pregnant females. Out of 40 positive females only 25 females turned up with their husbands. Two husbands were turned out positive for β-TT.
Discussion and Conclusion- Present study demonstrates that set of cost effective screening tests like Mentzer index, England & Fraser index, RBC count and Green & Kind index with routine hemogram data (RBC and Hb) in microcytic cases can effectively discriminate between β-TT and Non β-TT. Diagnosis of β-TT can be reliably done by HPLC and HbA2 quantitation by elution with HbA2≥ 3.8%
