Red cell deformability versus capillary diameter in diabetic foot

21 patients complaining of diabetes mellitus complicated by diabetic foot, mainly gangrene [15 subjects] and diabetic ulcer [six subjects] were selected. 25 patients served as control for RBCs deformability and five control subjects for measuring capillary diameters. A full clinical examination, urine analysis for sugar and fasting blood sugar were estimated to them. A full histopathological examination was done including measurement of capillary diameters using morphometric eye lens and ordinary light microscope. The longitudinal and transverse diameters were measured and the mean capillary diameter was calculated in five high power field in every section. RBCs deformability test was carried out and the RBCs flow time was measured. The mean capillary diameter for diabetics was significantly lower than that for controls and the red blood cell flow time was also significantly longer. There were no significant changes in capillary diameter and red cell flow time in both NIDD and IDD. The capillary diameter and RBCs deformability were inversly proportionate with the duration of the disease. Endothelial swelling as well as endothelial proliferation were noticed in 78.94%, 100% showed thickened basement membrane. So in diabetes more rigid red cells and increased viscosity at low shear rate are likely to promote stasis in the capillaries and postcapillary venules, sites where the very rarly vascular lesions in diabetes characteristically occur