[Multicenter evaluation of thr Abbott glycosylated hemoglobin assay on IMx]

The Abbott IMx glycated hemoglobin assay was evaluated in a multicentre study. This method utilizes boronate affinity chromatography, and ion-capture technology. This assay determines both total glycohemoglobin (% GHb) and percentage of hemoglobin Alc (% HbAlc). The precision of the assay was evaluated: the intra-assay and interassay coefficients of variation were judged to be satisfactory (< 6.5%). We determined the accuracy of the assay by comparison with a reference HPLC assay for 603 specimens; coefficients of correlation were between 0.88 and 0.96. We studied the interference of bilirubin and glucose and found no interference at usual concentrations. The presence of abnormal hemoglobins (HbF and some Hb structural variants HbS, HbC) was not detected with the Abbott IMx assay; however, this assay showed no significant interference from the hemoglobin variants tested for heterozygous hemoglobinopathies (percentage of abnormal hemoglobin < 60%). We also determined normal values for HbAlc with this technology (164 specimens): 4.1 to 6.1%.