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Novel Equation for Correction of Glycated Hemoglobin and Calculation of Carbamylated Hemoglobin in Diabetic Uremic Patients

Author Affiliations

  • 1Department of Medical Biochemistry, Faculty of Medicine, Ain Shams University, Cairo, EGYPT

Res.J.chem.sci., Volume 3, Issue (12), Pages 6-11, December,18 (2013)


Carbamylated hemoglobin, as a measure of uremic control, has not gained wide acceptance like glycated hemoglobin as a measure of diabetic control, probably due to its difficulty of estimation. Furthermore, earlier studies have shown that hemoglobin A1c concentrations, measured by cation-exchange based methods, were higher in uremic patients. Our aim was to find a mathematical equation for correction of hemoglobin A1c and easy estimation of hemoglobin carbamylation in uremic patients. We performed in vitro glycation and carbamylation of hemoglobin. Hemoglobin A1c was estimated using cation-exchange based assay method, while carbamylated hemoglobin was estimated by high performance liquid chromatography. The results of in vitro glycation of hemoglobin were compared with those of uremic and diabetic uremic patients. We found that urea in the incubation medium increased the hemoglobin A1c value in the in vitro experiments. Moreover, uremia increased its levels in uremic patients compared to healthy subjects and in diabetic uremic patients compared to diabetic non-uremic patients. We extracted a mathematical equation for the correction of hemoglobin A1c and easy estimation of hemoglobin carbamylation in samples with high urea levels. Studying the difference between hemoglobin A1c measured by cation-exchange based methods and affinity based methods against carbamylated hemoglobin estimated by high performance liquid chromatography and performing further studies on a large cohort of patients will be necessary to confirm these findings and to establish the definite mathematical equation for correction of hemoglobin A1c and determination of the extent of hemoglobin carbamylation in uremic patients.


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