[Erythrocyte aggregation in patients treated by plasma exchange or plasma administration]

The kinetic (aggregation times) and rheological (dissociation threshold) parameters or erythrocyte aggregation were determined before and immediately after each plasma epuration, using a device based on the analysis of the back scattered light by a blood suspension. We used two techniques of plasma épuration: a) classical plasma exchange: 8 multiple myelomas, 6 Waldenström diseases, with 42 procedures tested; b) plasma treatment/cascade filtration: one Waldenström disease with 9 procedures tested and 37 procedures in one patient suffering from hypercholesterolemia. We have completed this study by checking the rheological parameters in 46 procedures applied in 6 patients with hypercholesterolemia. In these patients, we have used the Kaneka technique (dextran sulfate). The parameters studied were: primary (Ta) and final (Tf) aggregation times, total (gamma D) and partial (gamma S) dissociation parameters. In all cases, the results showed an important decrease of Ta and Tf (with good improvement) and an increase of dissociation parameters showing the efficacy of such therapies. Erythrocyte aggregation constitutes a good panel of parameters to appreciate abnormalities before and after plasma epuration.