Calf sweat lactate in peripheral arterial occlusive disease

The energy metabolism of sweat glands was studied to evaluate the reduction in oxygen delivery in the tissue of patients with peripheral arterial occlusive disease. We compared lactate concentration in pilocarpine-iontophoresis sweat collected from the middle calf area ([ L]sw) of 10 healthy subjects (group 1) and 84 patients suffering from intermittent claudications (group 2, n = 49), from rest pain (group 3, n = 21), and from severe ischemic skin changes (group 4, n = 14). In addition, the effect of a vasoactive drug (naftidrofuryl, 600 mg) or placebo infusion on [L]sw was investigated (n = 30). Results (means +/- SE) showed that 1) [L]sw (mmol/l) increased significantly with the severity of the symptoms: group 1 = 16.5 +/- 0.4, group 2 = 18.7 +/- 0.4, group 3 = 22.8 +/- 0.9, and group 4 = 27.5 +/- 2.0; and 2) [L]sw was reduced by 10% (P less than 0.01) after naftidrofuryl infusion, whereas there was no change after placebo infusion. We suggest that lactate in calf sweat is a good indicator in the evaluation of the severity of peripheral occlusive arterial disease and in assessing the efficiency of vasoactive drug treatment.