Abnormal hemoglobin variants – a single center hospital-based study: Comparison of sensitivity of three red cell indices for the diagnosis of beta thalassemia trait

Introduction The frequency of beta thalassaemia gene in India is 3.3 %, with regional variations. There is lack of data regarding the prevalence of beta thalassaemia in the state of Kerala. We studied the clinical and haematologic profile of cases with haemoglobinopathy, with special emphasis on beta thalassaemia trait(BTT). The sensitivity of Mentzer Index(MI), Ricerca Index(RI) and Green & King Index(GKI) for diagnosing BTT was also studied. Materials Cases with a new diagnosis of haemoglobinopathy, at a single center in Kerala, during the period from November 2023 to October 2024 were included based on chart review. High performance liquid chromatography was used to detect abnormal haemoglobin variants. Clinical presentation, the red cell parameters – haemoglobin, RBC count, mean corpuscular volume, and red cell distribution width were recorded. MI, RI and GKI in BTT cases were calculated. Results There were 1021 new registrations in Haematology clinic. 72 cases had abnormal haemoglobin variants. Of which, 60 cases(83.33 %) had BTT. Sickle haemoglobin was present in 7 cases(9.7 %). Median age of the BTT cases was 37.5 years (range 3 – 79). 60 % were females. Fatigue was the predominant symptom – reported by 65 % cases. 86.67 %(52/60) had anaemia. Median Hb was 10 g/dL(range 7 – 14.1). 15 % had hemolytic anaemia. The sensitivity of MI, RI, and GKI in diagnosing BTT was 51.67 %, 86.67 %, and 53.33 %, respectively. Conclusions BTT is a significant cause of anaemia in our population. RI has better sensitivity than MI and GKI for diagnosis of BTT.