Serum Fructosamine Concentration as an Index of Glycemia in Cats With Diabetes Mellitus and Stress Hyperglycemia

Abstract

The purpose of this study was t o evaluate fructosamine concentrations in clinically healthy cats, sick cats with stress hyperglycemia, and untreated diabetic cats t o determine the usefulness of this test in diagnosing diabetes mellitus in cats, and in differentiating the disease from stress-induced hyperglycemia. In addition, we evaluated if the degree of glycemic control in cats treated for diabetes influenced their serum fructosamine concentrations. In the 14 sick cats with stress hyperglycemia, the median serum fructosamine concentration (269 @mol/L) was not significantly different from the median value in the 26 clinically normal cats (252 pmol/ L). Two of the 14 cats with stress hyperglycemia (14.3%) had serum fructosamine concentrations above the upper limit of the reference range (175 t o 400 pmol/L); on the basis of these results, the test specificity was calculated as 0.86. In 30 cats with untreated diabetes mellitus, the median serum fructosamine concentration was 624 pmol/L, markedly higher than the value in either the normal cats or the cats with stress hyperglycemia. All but 2 of the 30 untreated n human diabetic patients, serum fructosamine concentra-I tion has been shown to provide a reliable assessment of short-term glucose homeostasis.'.' Fructosamine assays are reported to be quick, technically simple, inexpensive, precise, fairly free of interference, and easily a~t o m a t e d .~.~ The fructosamine test also detects deteriorating glycemic control faster than measurement of glycosylated hemoglobin, another test commonly used to monitor glycemic control in human diabetic patient^.'.^.'.^The term "fructosamine" refers to albumin and other plasma proteins that have been linked to a sugar (usually glucose) by a nonenzymatic chemical reaction, a process known as glycation. The serum fructosamine concentration is proportional to the blood glucose concentration over the life span of the glycated protein being measured (eg, in humans, 2 to 3 weeks in the case of albumin). Therefore, measuring the serum fructosamine concentration is a means of assessing the average blood glucose concentration in an individual over the preceding few weeks. Although the life span of albumin in cats is not known, it is assumed to be similar to that in dogs, approximately 1 to 2 weeks.' The glycation of hemoglobin over the life span of erythrocytes is commonly thought of as the classic example of this process and is a reflection of the average blood glucose concentration over the life span of the red blood cells (70 and 120 days in cats and humans, respectively).","

Fructosamine and glycated hemoglobin in the assessment of glycaemic control in dogs

“…This correlation was even higher when stress hyperglycaemic cats were excluded. When cats with stress hyperglycaemia were analysed alone, no correlation was found [2]. A high correlation between fructosamine and glucose concentrations (r = 0.90) was obtained when both healthy and sick cats were included [9].…”

Blood glucose level as an insufficient indicator of feline diabetes mellitus: a case report

“…The concentration of fructosamine in serum is a reflection of mean blood glucose level over the preceding one to three weeks. The reliability of the fructosamine assay has been documented in several studies (Crenshaw et al 1996;Elliot et al 1999;Rios and Ward 2008). However, in some European countries (e.g., Poland) an access to its determination in animal blood samples is very limited and requires often a long-distance dispatch (e.g., to Germany or Switzerland) and significant expense.…”

Avaliação dos níveis de frutosamina em gatos sob estresse agudo e crônico

“…No presente trabalho, um estresse agudo, de dura- Entretanto, no trabalho de Crenshaw et al 12 não se observou correlação entre os valores da frutosamina e glicose séricas no grupo de animais com hiperglicemia por estresse. Houve correlação (r = 0,7; n = 100; p < 0,001) apenas quando os valores foram analisados como um único grupo (saudáveis, DM sem tratamento, DM durante tratamento e hiperglicemia por stress), com valores ainda maiores quando se excluiu os animais com hiperglicemia por estresse.…”

“…Estes autores relataram que o aumento da frutosamina associado ao estresse apresenta magnitude inferior ao observado em felinos diabéticos 12 . O estresse crônico (superior a cinco dias) também demonstrou influência sobre os valores de frutosamina, entretanto estes animais, em média, também não apresentaram hiperglicemia, não devendo representar uma dificuldade na diferenciação de um possível DM.…”

“…O estresse crônico (superior a cinco dias) também demonstrou influência sobre os valores de frutosamina, entretanto estes animais, em média, também não apresentaram hiperglicemia, não devendo representar uma dificuldade na diferenciação de um possível DM. Este aumento da concentração sérica de frutosamina também se manteve dentro do intervalo de referência, como encontrado em estudos anteriores 4,10,12,16 .…”