LEUKOCYTE ACTIVITY IN THE MICROCIRCULATION OF THE LEG IN PATIENTS WITH CHRONIC VENOUS DISEASE

Purpose: It has been suggested that leukocyte trapping and activation in the microcirculation of the leg skin causes lipodermatosclerosis an d ulceration in patients with chronic venous disease. Ambulatory venou s hypertension is accepted as the physiologic factor that leads to ulc eration. We investigated leukocyte endothelial adhesion in patients wh o were subjected to short-term venous hypertension. Methods: Two group s of patients with venous disease were studied: group 1, varicose vein s with skin changes (n = 15); and group 2, varicose veins without skin changes (n = 15). Blood samples were taken from a foot vein before an d after standing for 30 minutes to raise the venous pressure in the lo wer limb, and after lying supine again for 10 minutes. The samples wer e analyzed for leukocyte surface CD11b and L-selectin (CD62L) expressi on using a flow cytometer. Plasma-soluble L-selectin was also measured using an enzyme-linked immunosorbent assay. Results: In patients with skin changes, median neutrophil CD11b levels fell from 4.66 to 3.83 a rbitrary units (p = 0.005, Wilcoxon) after 30 minutes of venous hypert ension. Median monocyte CD11b levels fell from 7.65 to 5.8 arbitrary u nits (p = NS, Wilcoxon) after venous hypertension and then fell furthe r to 5.43 arbitrary units (p = 0.02 vs baseline; Wilcoxon) when the ve nous hypertension was removed. Neutrophil and monocyte L-selectin leve ls also fell in response to venous hypertension, remaining low even af ter venous hypertension was removed. A similar pattern was seen in pat ients with uncomplicated varicose veins. There was a rise in soluble L -selectin in the plasma of both groups of patients after venous hypert ension, reflecting leukocyte adhesion to endothelium. In the group of patients with skin changes the level of soluble L-selectin rose from 6 95 ng/ml to 836 ng/ml (p = 0.02, Wilcoxon), and in the group without s kin changes the rise was from 700 ng/ml to 801 ng/ml (p = 0.02, Wilcox on). Conclusion: Venous hypertension results in sequestration of the m ore activated population of neutrophils and monocytes in the microcirc ulation of the leg in patients with venous disease. These cells bind t o the endothelium, releasing L-selectin, and do not emerge from the li mb when venous hypertension is reversed. These findings do not differ between patients with varicose veins and those with skin changes.