Evaluation of Manual Hb A1C Determination Methods in Diabetic Patients with Sickle Cell Trait
AbstractBackground and Aim
HbA1c is an irreversible non-enzymatic glycation at one or both NH2- terminal valines of the β –chain. Sickle hemoglobin, or HbS, has a valine for glutamic acid substitution at position 6 of the β chain. The prevalence of sickle cell trait reported to be 2.5% in Basrah city. The hemoglobin A1C (A1C) test can lead to false outcomes resulting in over- treatment or under-treatment of diabetes in people with inherited hemoglobin variants.
This study focus on the evaluation of sickle cell trait effect on HbA1c measurement by the minicolumn ion exchange resin methods and compare them with Biorad Variant (HPLC method).the one of methods certified by national glycohemoglobin standardization program (NGSP)Materials and Methods
60 diabetic patients identified with sickle cell trait were recruited in this study .Blood sample collect in EDTA tubes and were assessed for hemoglobin A1c using 3 methods commercially available and most fequently used for routine investigations. Stanbio Glycohemoglobin (Pre- Filâ), HUMAN Glycohemglobin HbA1-Test ( Fast Ion Exchange Resin Separation Method ) ,and the Bio-Rad VARIANT Hemoglobin A1c (HPLC ) methodResults
Mean age group for patient were 39.6 yrs with their mean blood glucose level of about 203 mg/dl , the average glycohemoglobin was 9.1% measured by Biorad Variant, compare to 7.57% and 7.99% for both Stanbio method and Human Method respectively, which show statistically significant difference (p<0.05). It also had been found that average difference between both manual methods (|Stanbio and Human) and Automated method (biorad variant HPLC) about (1.5, 1.15) . These difference show a significant statistical correlation with hemoglobin S level with r =0.856; p value<0.001.Conclusion
This study demonstrate the significant difference in Glycated hemoglobin measurements between different methods commercially available in local markets which had been shown to give false negative results in sickle trait patients when compared to those methods standardized by NGSP system. And recommend that such methods to be avoided in patient with sickle cell trait.
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