Immunohistochemical investigation of dermal capillaries in chronic venous insufficiency.

Skin biopsies from the area of the medial malleolus of 24 patients with chronic venous insufficiency, of 5 patients without signs or history of chronic venous insufficiency and of seven corpses without manifestation of chronic venous insufficiency, were sectioned and stained with hematoxylin and eosin and with Ki-67, a monoclonal antibody expressed in the nuclei of proliferating cells. Hematoxylin- and eosin-stained sections of all specimens were assessed blindly to determine the state of capillary increase in stasis dermatosis. Twenty-four patients were found to have different stages of stasis dermatosis. During the examination of the Ki-67 frozen sections, close attention was paid to the capillary bed of all sections for any Ki-67-positive nuclei in capillary cells. None of the three groups showed positive staining of nuclei in capillary cells. This finding proves that there is no capillary proliferation, but an elongation and distension of the capillaries.