Abstract
Background Hemoglobin variants may cause mismanagement of diabetes resulting from false glycated hemoglobin (HbA1c) results. The aim of this study was to compare the results obtained from three different HbA1c assay systems among patients with sickle cell trait (SCT) at Faiha Specialized Diabetes, Endocrine, and Metabolism Center (FDEMC) in Basrah. Methods A cross-sectional observational study was done in FDEMC in Basrah on patients with established diagnoses of diabetes mellitus. All samples were analyzed at FDEMC laboratory by using three different systems: Roche Cobas Integra Gen.2 (COBAS INTEGRA(®) 400 plus analyzer immunoassay) (Roche Diagnostics, Indianapolis, IN), a turbidimetric inhibition immunoassay (TINIA), Bio-Rad Variant II Turbo (Bio-Rad, Hercules, CA) Ion exchange HPLC method, and Bio-Rad D-10 (A1c program) (Bio-Rad, Hercules, CA) Ion exchange HPLC method. Results We enrolled 139 persons with diabetes and SCT compared with 70 controls with diabetes and no SCT. A significant difference in the mean HbA1c levels between Roche Cobas Integra Gen.2 and Bio-Rad Variant II Turbo in comparison with Bio-Rad D-10 (A1c program) across all strata of HbA1c in SCT. The highest difference was -0.5% in the stratum of HbA1c 7 to 9% group in Roche Cobas Integra Gen.2, while it was +0.8% in the stratum of HbA1c less than 7% in the SCT group. For the control group, the highest difference was -1.3%, seen in the stratum of HbA1c, more than 9% in the Roche Cobas Integra Gen.2, while the highest difference in the Bio-Rad Variant II Turbo was +0.5% in the same stratum. In both groups, the results of HbA1c were mostly higher in the Bio-Rad Variant II Turbo and lower in Roche Cobas Integra Gen.2. Conclusion Roche Cobas Integra Gen.2 and Bio-Rad Variant II Turbo methods are not preferred to be used in HbA1c estimation in areas where SCT is prevalent. Diagnosing or follow-up of glycemic control in patients with SCT needs critical reappraisal because of the limitation of methods used to measure HbA1c in Basrah.