Labile Hemoglobin A1c: Unexpected Indicator of Preanalytical Contraindications

[摘要] To the Editor:Labile hemoglobin A1c (Hb A1c), or pre–Hb A1c, is an intermediate in the synthesis of Hb A1c and is characterized by the reversible binding of glucose to Hb as a Schiff base (1). Its biological variation is related to recent fluctuations in glycemia and cannot provide suitable retrospective information on a patient's long-term glycemic balance. Therefore, labile Hb A1c must be eliminated from the measured Hb A1c over the 6–8 weeks before sampling in order to estimate the quality of diabetic control (2, 3).Most of the Hb A1c methods available on the market either are insensitive to labile Hb A1c (e.g., immunologic assays, affinity assays) or separate or even eliminate it during analysis (e.g., by HPLC or low-pressure liquid chromatography) (4). It might be of interest, however, to take labile Hb A1c values into account when interpreting Hb A1c results if an HPLC system capable of separating this fraction can be used. In some circumstances, measurements of labile Hb A1c might serve to detect preanalytical problems that could lead to inappropriate clinical decisions.We report on 2 recent …

[学科分类] 过敏症与临床免疫学