Pediatric reference intervals of the hemoglobin fractions HbA₂, HbF and HbA₀ using high-performance liquid chromatography and capillary electrophoresis

Introduction: β-thalassemia is a common genetic disorder with an estimated prevalence of 80-90 million carriers worldwide. As elevated hemoglobin A₂ (HbA₂) is a primary feature of carriers, hemoglobin fraction analysis is a common technique used for initial screening. However, pediatric reference intervals (RIs) are scarce. Hence, the aim was to establish pediatric RIs of hemoglobin fractions using high-performance liquid chromatography (HPLC) and capillary electrophoresis (CE).

Methods: Samples were collected from assumed healthy children and adolescents of 1-18 years. Analyses were conducted using the Tosoh Automated Glycohemoglobin Analyzer HLC-723®G11 (Tosoh G11, HPLC) and the Capillarys 3 Octa (CE). Data were investigated for need of partitioning by both age (1-6 years vs. 6-18 years) and sex.

Results: In total, 189 and 196 subjects were included in the statistical analysis of HPLC and CE, respectively. The 95% RI of HbA₂ was 2.00-2.90% by HPLC and 2.2-3.0% by CE. Partitioning of data was not clinically relevant by HPLC. However, partitioning by age was suggested by CE.

Conclusion: RIs of hemoglobin fractions in individuals of 1-18 years using commercially available HPLC and CE equipment were reported. This is the first report of a pediatric RI of HbA₂ using the Tosoh G11.