Comparison of red blood corpuscle indices versus hemoglobin high-performance liquid chromatography as a screen for hemoglobinopathies in pregnant women

Abstract

Introduction: Beta-thalassemia plagues India and thalassemia screening of pregnant women is crucial. Hemoglobin (Hb) high-performance liquid chromatography (HPLC) (Hb-HPLC) is the gold standard, however in distant places it is rarely an option. While data on the use of red blood cell (RBC) indices to screen pregnant women for thalassemia trait is still developing, a sensitive and specific RBC index is needed to test for beta thalassemia. In service situations, these affordable indices may be useful without HPLC. Objective: We aimed to determine the role of red blood corpuscle indices as a screening tool to differentiate between iron deficiency anemia (IDA) and hemoglobinopathies in pregnant women and to find out the most sensitive and the most specific index. Methods: With ethical approval, 500 patients were evaluated from February 2020 to August 2021. Complete blood Counts and peripheral blood smears were performed. Participants with microcytic hypochromic anemia were included. On these patients, the RBC indices (i) Shine and Lal, (ii) Mentzer’s index, (iii) red cell distribution width index, and (iv) Srivastava were calculated. Ferritin, iron, and total iron-binding capacity levels were also tested. Hb-HPLC was utilized as the gold standard. The Mann– Whitney U-test was used to compare continuous variables between groups. Sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy were calculated for various metrics. A P < 0.05 was statistically significant. Results: Hb-HPLC showed 29 (5.8%) heterozygous beta thalassemia and 471 (94.2%) IDA. Based on the updated cutoff value (4.727), Srivastava Index was the best screening tool. Conclusion: RBC indices can distinguish IDA from beta thalassemia in pregnant women and are valuable screening tools in service settings.