Diagnostic Performance of RBC Indices in Beta Thalassaemia Trait

Beta thalassaemia trait is one of the most common forms of thalassaemia in Bangladesh. This clinical entity usually remains undiagnosed because they present with mild anaemia or sometimes no anaemia. Determination of trait is the mainstay of prevention of thalassaemia. RBC indices can provide valuable diagnostic tool for beta thalassaemia trait. This was a hospital based cross-sectional, analytical study, done at Department of Paediatrics, Rangpur Medical College Hospital, Rangpur, Bangladesh from July 2014 to June 2016. A total of 150 anaemic children, aged 1-15 years from inpatient and outpatient department were included by purposive sampling. Blood samples were collected and sent to the Department of Biochemistry, Rangpur Medical College to determine the value of RBC indices. Out of 150 anaemic children 37(24.66%) children were diagnosed as E-trait, 9(9%) E-disease 6(4%) as E-Beta thalassaemia, 1(0.66%) had error in the report, a total of 53 children were excluded from the study. Finally, 32(21.3%) children, diagnosed as beta thalassaemia trait and 65(43.33%) children, diagnosed as normal Hb variant, so a total of 97 children were enrolled in this study. Age of the children was 1-15 years. Their mean age was 6.4 years. Male female ratio was 1.15:1. There was significant difference of HbA₂ between BTT and non BTT group of participants (p value <0.001). Value of MCV and MCH were significantly greater in BTT than non BTT group (p value <0.05). Sensitivity, Specificity, Positive predictive value, Negative predictive value and Youden index of MCV were 81.25%, 90.76%, 81%, 90% and 71 respectively. Sensitivity, Specificity, Positive predictive value, Negative predictive value and Youden index of MCH were 84.37%, 92.30%, 84%, 92% and 76 respectively.