Quantification of HbA2 in patients with and without β-Thalassemia and in the presence of HbS, HbC, HbE, and HbD Punjab hemoglobin variants : Comparison of two systems

Abstract

We studied whether problems quantifying hemoglobin A2 (HbA 2) could be resolved by using capillary electrophoresis. HbA2 2was quantified on whole blood samples from patients with and without β-thalassemia trait and patients heterozygous for HbE, HbS, HbC, and HbD Punjab using the VARIANT II β-thalassemia (Bio-Rad, Hercules, CA) and Capillarys 2 (Sebia, Norcross, GA). HbA2 results in patients with and without β-thalassemia trait were lower with the Capillarys 2 system. Reasonable HbA2 results were obtained for patients with HbD Punjab and HbE traits on the Capillarys 2. HbA2 results for patients with HbS, heterozygous and homozygous, were similar by both methods. Interference due to coelution for HbA2 results for patients with HbC trait was noted on the Capillarys 2. Between-day imprecision on the VARIANT II is less than that for the Capillarys 2 system. The Capillarys 2 is superior to the VARIANT II for quantifying HbA2 in the presence of HbE and HbD Punjab traits. The Capillarys 2 offers only slight advantages over the VARIANT II for quantifying HbA2 in the presence of heterozygous and homozygous HbS. The Capillarys 2 gives inferior HbA2 results for patients with HbC trait. © American Society for Clinical Pathology.