SERUM 1,5-ANHYDROGLUCITOL (1,5-AG) - NEW CLINICAL MARKER FOR GLYCEMICCONTROL

We review the use of 1,5-anhydroglucitol (1,5 AG) in diagnosing and mo nitoring patients with diabetes. This six-carbon chain monosaccharide is one of the major polyols present in humans. Its concentration in se rum is normally about 12 to 40 mu g/ml. This substance is derived main ly from food, is well absorbed in the intestine, and is distributed to all organs and tissues. It is metabolically stable, being excreted in the urine when its level exceeds the renal threshold. It is reabsorbe d in the renal tubules, and is competitively inhibited by glucosuria, which leads to a reduction in its level in serum. The correlation betw een this reduction and the amount of glucose present in urine is so cl ose that 1,5 AG can be used as a sensitive, day-to-day, real-time mark er of glycemic control. It provides useful information on current glyc emic control and is superior to both HbA(1c) and fructosamine in detec ting near-normoglycemia.