Evaluation of the V8 E-Class, a Novel Automated Capillary Isoelectric Focusing Instrument for Hemoglobinopathy Screening.

Abstract

We evaluated the performance of a novel capillary isoelectric focusing (CIEF) application for hemoglobinopathy screening on the recently introduced V8 E-Class platform. Analytical performance of the V8 E-Class was evaluated and included assessment of hemoglobin A2 (HbA2) imprecision; linearity for HbA2, fetal hemoglobin (HbF), and sickle hemoglobin (HbS); and carryover for HbS. Furthermore, a method comparison with the Minicap Flex Piercing (Sebia, Lisses, France), the Variant Classic (Bio-Rad Laboratories, Hercules, CA), and the G8 (Tosoh Europe, Amsterdam, the Netherlands) was done to assess analytical and clinical concordance. Total HbA2 imprecision was 3.26% and 3.14% for normal and elevated HbA2 controls and 5.16% and 3.58% for a normal and a heterozygous HbS patient sample, respectively. HbA2, HbF, and HbS showed acceptable linearity, and no carryover was observed. The method comparison showed good analytical concordance (r > 0.95) except for a homozygous HbS subset (r = 0.532-0.704). A comparable phenomenon was seen for the clinical concordance with good agreement in samples without variants (weighted κ > 0.80) but poorer agreement in HbS samples (κ < 0.30). Good analytical performance was demonstrated for this novel CIEF application for hemoglobinopathy screening. Method comparison showed generally good correlation but highlights the need for standardization. Finally, software optimization could further add to its use for routine hemoglobinopathy screening.