RESUMEN
The relation between factor VIII coagulant [F VIII:C], Von Willebrand Factor [vWF] and diabetic retinopathy was studied in this work. The study was conducted upon 38 insulin dependent diabetics, 14 without retinopathy, 13 with background retinopathy and 11 with proliferative retinopathy. They were matched to 10 non-diabetic controls. The study revealed that vWF activity increases significantly in diabetics in general. This increase tended to go in parallel with the increase in the severity of retinopathy. However, no significant difference in vWF activity was found between diabetics with and without retinopathy. This means that vWF has no role in the pathogenesis of retinopathy. On the other hand, F VIII:C showed marked increase in the diabetics in general. This increase was more prominent with proliferative retinopathy than background retinopathy. However, no difference was found between existence of absence of retinopathy. In conclusion, both F VIII:C and vWF levels are increased in diabetics, but their relation to the process of vascular endothelium damage are merely a sequence of vascular damage in case of vWF, while F VIII:C increase represents activation of the hemostatic system in diabetic patients