[Aggregation of erythrocyte suspensions of diabetic patients in dextran 70 solutions]

Our previous studies have shown an erythrocyte hyperaggregation during diabetes. This hyperaggregation phenomenon seems usually be promoted by quantitative plasma protein's changes mainly fibrinogen. The aim of the present work is to appreciate the possible effect of only diabetic red cells on aggregation induced by dextran 70 (Dx 70). Aggregation measurements were performed with Sefam aggregometer. Patients were insulin-dependent (IDD) and non insulin-dependent diabetics (NIDD), divided in two groups of 11 well controlled diabetics (HbA1C 6.8 +/- 0.5%) (7 IDD and 4 NIDD) and 11 poorly controlled diabetics (HbA1C 10.8 +/- 2.7%) (7 IDD and 4 NIDD). They were compared with a control group consisting of 22 healthy subjects. Results can be summarized as follows: red cell aggregation induced by Dx 70 was not significantly different between the well controlled diabetics and controls. Similar results were obtained for the poorly controlled diabetics. By contrast, when studying red cell aggregation in autologous plasma (H = 40%), aggregation was found to be significantly more important in both diabetic groups than that of the controls. Thus, results emphasize the importance of suspending medium in erythrocyte hyper-aggregation phenomenon during diabetes. Cellular factors do not seem to interfere on aggregation phenomenon for diabetics included in this study.