Effects of different anticoagulants on glycated albumin quantification

INTRODUCTION: In the last 20 years glycated albumin (GA) measurement has been demonstrated to be a reliable glycation marker and recently as the most innovative one in western countries. Glycated albumin has been already adopted by some Asian countries due to its usefulness in diabetes screening. The aim of the present study was to investigate for the first time the effects of different anticoagulants on GA assay. MATERIALS AND METHODS: From each of 60 patients a serum tube and K(3)EDTA, Li-Heparin and NaF-EDTA containing tubes were collected. All tubes were from Sarstedt (Verona, Italy). Glycated albumin was measured in duplicate in each sample tube in a single analytical run with quantILab glycated albumin (Instrumentation Laboratory SpA - A Werfen Company, Milan, Italy) on Architect c8000 analyser (Abbott SRL, Rome, Italy). Comparison of GA% in evaluated tubes was made by paired Wilcoxon test. RESULTS: Median and interquartile range GA% concentrations were 15.4% (13.2 - 19.1) in serum, 15.7% (13.6 - 19.9) in K(3)EDTA, 15.6% (13.3 - 19.7) in Li-heparin and 15.5% (13.1 - 19.3) in NaF-EDTA samples, respectively. Glycated albumin mean relative bias respect to serum was within desirable bias derived from biological variation studies (± 2.9%) when K(3)EDTA (+ 2.8%), Li-heparin (+ 0.9%) or NaF-EDTA (+ 0.1%), were used as anticoagulants. CONCLUSIONS: Our results demonstrate that the GA% assay is not affected by relevant interferences when K(3)EDTA, Li-heparin or NaF-EDTA are used as anticoagulants, so they can be used interchangeably without a relevant impact on the clinical use of the test.