[Assay of fructosamine. Value and limits in diabetology]

Fructosamine test using a Nitroblue Tetrazolium (NBT) method offers many advantages: quickness, reproducibility, easy automation and unexpansiveness, but a standardization of the different methods is needed. The results can be expressed in absolute value of equivalent DMF per liter, except in pregnancy where mumol per g of protein is used. The interpretation of the results can be difficult in case of quantitative and/or qualitative proteins abnormalities: icterus and severe chronic renal insufficiency. Fructosamine is significantly higher in diabetic patients. It gives a good correlation with glycated haemoglobin but the provided information is different, concerning a shorter period of 2 to 3 weeks and perhaps more sensitive to recent glycaemic variations. Fructosamine test does not seem to be a good screening test for diabetes and impaired glucose tolerance. The test indications of the assay could be: situations where the dosage of glycated haemoglobin is not interpretable, diabetic pregnancy follow-up and short term evaluation of a therapeutic change on glycaemic control. However, the individual significance of fructosamine concentration remains to be assessed and seems to be less accurate than glycated albumin.