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Peripheral occlusive arterial disease (P.O.A.D.) is one of the situations in which hemorheological abnormalities are usually described. However the clinical relevance of hemorheological measurements in angiologic practice remains to be defined. The aim of the study was to investigate whether hemorheological disturbances are associated with alterations in oxygen diffusion and prognosis of the arterial disease. Three groups of patients were included in this work. First, a study was realized on 160 nondiabetic P.O.A.D patients (suffering from intermittent claudication to critical limb ischemia) in order to evaluate the possible influence of hemorheological disturbances on oxygen diffusion in distal tissue. A control group of 30 subjects matched for age and sex was also studied. A second study was performed on 80 diabetic P.O.A.D. patients (stage III and IV of Leriche and Fontaine classification) to determinate if hemorheological parameters could be considered as prognostic factors in the P.O.A.D. course. Hemorheological parameters were determined on different devices: red blood cell (RBC) aggregation by Myrenne aggregometer, blood and plasma viscosities by MT 90 falling ball viscometer. Transcutaneous oxygen pressure was measured by Radiometer TCM2 oxygen monitor. Several rheological parameters of non diabetic patients suffering from P.O.A.D. were significantly higher than those of control group subjects : blood viscosity (p < 0.05), plasma viscosity (p < 0.001), erythrocyte rigidity index (p < 0.01) and fibrinogen level (p < 0.0001). In the nondiabetic patients TcPO2 was negatively correlated with RBC aggregation, erythrocyte rigidity index and hematocrit /viscosity ratio. The diabetic patients who needed major amputation (above or below knee) presented significantly increased hemorheological parameters (blood viscosity, RBC aggregation, RBC rigidity index, hematocrit/viscosity ratio, fibrinogen level) compared to diabetic who had not been major amputated (no amputation or only toes' amputation). Our finding suggests that hemorheological factors (1) may influence oxygen transfer to distal tissues by maldistribution of blood flow and (2) may have prognostic significance in chronic peripheral occlusive arterial disease.

Trace elements have been shown to improve red blood cell (RBC) deformability: zinc in sickle cell disease and magnesium in an in vitro model of chemically rigidified erythrocytes. In this study, we investigated the effect and the influence of incubation time of zinc or magnesium on an in vitro model of rigidified RBCs by heating. Erythrocyte rigidity was determined by viscosimetry at high shear rate by a falling ball viscosimeter MT 90. In the first part of the study, six normal volunteers participated. Viscosimetry was performed on native blood before and after heating the sample for 10 min at 50 degrees C. Therefore, increasing concentrations of zinc gluconate (final concentration: 0.5-4 g/L) or isotonic NaCl as control medium were added to the sample. Heating induced a twofold increase in all indices of RBC rigidity (p < 0.05). At all these concentrations of zinc, a highly significant, dose-related fluidifying effect was observed (40-70%): this effect was immediately obtained and did not change over 60 min. Even at the highest concentration, recovery was not complete. In the second part of the study, we studied magnesium's effects on blood. In a first protocol, whole blood was rigidified by heating at 56 degrees C for 10 min, and the correcting effect of 5 min of incubation at 37 degrees C of RBCs in 150 mmol/L NaCl, MgSO4, magnesium acetate, and magnesium gluconate was investigated. In a second protocol, the same incubation with NaCl and magnesium salts was made on blood that had not been previously heated.(ABSTRACT TRUNCATED AT 250 WORDS)

The objective of this study was to determine the prevalence and clinical significance of elevated antiphospholipid antibodies (APA) in a large series of patients admitted to a department of Internal Medicine. At the end of entry phase, 1014 patients were tested (488 males-526 females, mean age: 66.7 years, range 18-97). Seventy-two (7.1%) patients were found APA positive at least once: 44 males and 28 females, mean age 69 years, range 23 to 94. Twenty fulfilled the criteria of Primary Antiphospholipid Antibody Syndrome: 10 patients were referred for deep vein thrombosis, 3 had history of deep vein thrombosis, 1 had both arterial thrombosis and a history of venous thrombosis; 2 had thrombocytopenia; 3 had stroke, 1 had a history of a stroke. One patient had SLE according to ARA classification. The most frequent associated disease was cancer: 14 patients, 9 had evolutive malignant disease, 5 were in clinical remission of neoplasia. Other clinical conditions included chronic and/or acute alcoholic intoxication (n = 8), severe atherosclerosis (n = 4), leg ulcer (n = 4). Insufficient data are available about the evolution, but 7 patients died in the year following diagnosis. Eight patients had fluctuations in APA detection: 2 initially APA positive became negative, 5 initially negative became positive and 1 patient was alternatively positive, negative and positive without steroid treatment. Thus, as expected, APA occur in a variety of clinical disorders. The association with cancer or alcoholic intoxication deserves further investigations.