Unmeasurable HbA1c result due to hemoglobinopathy

The aim of this study was to show the interference caused by hemoglobinopathy in the measurement of hemoglobin A1c (HbA1c). In our case presentation, we reported two patients whose HbA1c values were unmeasurable when using our laboratory's cation exchange chromatography. We detected HbSβ+ and HbSC variants by remeasuring the samples with another chromatography instrument. Measurement of HbA1c is a commonly performed procedure for the diagnosis of diabetes and for the assessment of blood glucose control in patients with diabetes. However, various hemoglobinopathies, chronic kidney disease, and abnormalities in red cell turnover rate may interfere with HbA1c quantification.