Diabetes mellitus is characterised by persistent hyperglycemia in all species. Fructosamine is a glycated protein reflecting blood glucose concentration during the preceding weeks. It has become a valuable analysis to differentiate persistent hyperglycemia from transient stress induced hyperglycemia in cats. It is also used to evaluate current therapy in diabetic patients. Although fructosamine is a well accepted analysis, it is sometimes regarded with scepticism. According to present literature there are significant differences between fructosamine concentrations in healthy cats and in diabetics. There are, however, overlaps, which means that single healthy individuals can have elevated values and diabetics may have values in the normal range.
Medical records from 56 cats with elevated fructosamine concentrations were reviewed in a retrospective study. Primary diabetes mellitus was the diagnosis in 82% of the cases, and cortisone therapy in 13%. Any interpretation of my results must take into consideration that this study only included cats with elevated fructosamine and that the two clinics involved regarded the fructosamine analysis as a very accurate test for diabetes.
The effects of storage time and temperature on fructosamine were investigated in a laboratory study. Serum samples from dogs and cats were stored in room temperature and under refrigeration during 3 days and analysed daily during this time. The changes in concentration were within a range of 10%.
In earlier observations at the laboratory, fructosamine results seemed to be distributed with two peaks, one around the normal mean value, and another peak at a markedly higher value. The high fructosamine concentrations, from the untreated diabetic cats in the retrospective study, seem to be distributed in a similar way. It is therefore reasonable to conclude that...
