[Pathogenesis of skin pathologic changes and ulceration].

Twenty-six patients with venous insufficiency and 15 normal controls were studied by local skin pathological and ultrastructure changes. Transcutaneous oxygen tension (Tcpo2) and tPA, PAI of venous blood were measured. Biopsies from the ulcerating and liposclerosis area showed pericapillary fibrins. The patients with severe venous disease resulting in liposclerosis or ulceration of the goiter area had Tcpo2 levels lower than the controls and patients with venous insufficiency but no skin changes. The more serious the skin changes in patients with venous insufficiency, the lower the fibrinolysis activity. We conclude that extravascular deposition of fibrins in patients with venous disease which block the diffusion and exchanges of oxygen between the blood and tissue is an important factor in the development of venous ulcerations. The decrease of fibrinolysis activity led to the decrease of removing pericapillary fibrins deposition, combined with extravascular fibrin caused venous ulceration.