Background. To date, peritoneal dialysis has been performed almost exclusively using dialysis solutions containing glucose as the osmotic agent. Use of these solutions is fraught with problems regarding adequate fluid removal from the body and is also associated with undesirable metabolic effects; hence the search for alternative osmotic agents. A dialysis solution with the glucose polymer icodextrin generates ultrafiltration on the principle of colloidal osmosis. The aim of the study was to establish the effect of icodextrin-base dialysis solution on the magnitude of ultrafiltration and evaluate selected metabolic parameters of patients treated by ambulatory peritoneal dialysis. Methods and Results. A total of 9 patients whose glucose-based solution was replaced by an icodextrin-based solution during the night-time exchange were evaluated. A control group of 9 patients used glucose-solution during all exchanges. Night-time bag ultrafiltration, blood pressure, and the serum levels of lipids, insulin, leptin, maltose, and amylase were determined before icodextrin administration (time 0), at one-month intervals (time 1, 2, 3), and one month after study completion (time 4). In icodextrin-treated patients, ultrafiltration rose from 246.5±60.5 ml (mean ± SEM) at time 0 to 593.1±87.4 ml; p<0,01, at time 1, to 547±67 ml; p<0.05, at time 2, and to 586.7±58.8 ml; p<0.01, at time 3, the icodextrin administration led to a rise in maltose from 0.02±0.01 g/l at time 0 to 0.1±0.1 g/l; p<0.01, at time 1, to 1.0±0.09 g/l; p<0.01, at time 2, and to 1.1±0.09 g/l; p< 0.01, at time 3, with a fall to zero values at time 4 (NS). Icodextrin administration was followed by a decrease in leptinemia from 34.6±17.2 ng/ml at time 0 to 21.7±8.9 ng/ml; p<0.05, at time 1, to 21.4±9.5 ng/ml; p<0.05, at time 2, and to 15.9±24.1 ng/ml; p<0.05 at time 4. Insulin and lipid levels were not affected. There was no change in the above parameters in the control group. Icodextrin-treated patients reduced their antihypertensive medication, but not statistically significantly. Conclusion. Icodextrin administration significantly increase ultrafiltration thus providing for effective control of hydration status without the need for high-level glucose-based dialysis solutions. The use of a glucose polymer-based dialysis solution is associated with a significant yet reversible rise in serum maltose. The decrease in leptin may signal a reduction in body weight after replacing glucose in dialysis solutions with icodextrin, or enhanced rates of leptin elimination as a result of ultrafiltration-induced convective transport.

        Key words: peritoneal dialysis, ultrafiltration, hydratation, icodextrin, osmotic agent, ma ltose, leptin, amylase, insulin.