Multicenter evaluation of hemoglobin A1c assay on capillary electrophoresis

Clin Chim Acta. 2013 Sep 23:424:207-11. doi: 10.1016/j.cca.2013.06.014. Epub 2013 Jun 20.

Abstract

Background: Hemoglobin A1c (HbA1c) measurement is currently used for the routine monitoring of long-term glycemic status, thus playing a fundamental role in the management of this disease. Since this marker has recently been recommended as an additional tool for diagnosing diabetes, it's of the utmost importance to ensure that the precision and accuracy of HbA1c methods are satisfactory.

Methods: We assessed the analytical performances of the Capillarys 2 Flex Piercing® analyzer and compared the results obtained with those from two other widely used HPLC instruments. Furthermore, we evaluated the convenience and ergonomics of the system in authentic routine work conditions in three centers.

Results: Within-laboratory (n=40) and between-laboratory (n=120) imprecision CV% using four blood samples with different concentrations of HbA1c were <3.4% and <3.1% using IFCC units and <2.1% and <2.0% using NGSP units, respectively. The obtained trueness (<3 mmol/mol, <0.3%) was highly satisfactory, nor was HbA1c measurement compromised by the presence of the commonly present hemoglobinopathies. The comparison made with established methods revealed excellent agreement (r>0.985).

Conclusions: The evaluated method is precise, accurate and robust, with a high throughput. It also allows the identification of the most frequent Hb variants and therefore may be a valid alternative to other methods currently proposed for routine use in clinical laboratories.

Keywords: CE; CV; Capillary electrophoresis; Coefficient of variation; Diabetes; HPLC; Hb; HbA(1c); Hemoglobin; Hemoglobin A(1c), glycated hemoglobin; High-performance liquid chromatography; IFCC; International Federation of Clinical Chemistry and Laboratory Medicine; NGSP; National Glycohemoglobin Standardization Program; SD; SQS; Sebia Qualification Samples; Standard deviation; cHb; carbamylated hemoglobin.

Publication types

  • Multicenter Study

MeSH terms

  • Automation, Laboratory
  • Biomarkers / blood
  • Diabetes Mellitus / blood
  • Diabetes Mellitus / diagnosis*
  • Electrophoresis, Capillary
  • Fetal Hemoglobin / metabolism
  • Glycated Hemoglobin / metabolism*
  • Hemoglobin A2 / metabolism
  • Humans
  • Observer Variation
  • Reference Standards
  • Reproducibility of Results
  • Sensitivity and Specificity
  • beta-Thalassemia / blood*

Substances

  • Biomarkers
  • Glycated Hemoglobin A
  • hemoglobin A1c protein, human
  • Hemoglobin A2
  • Fetal Hemoglobin