Search

Background: Evidence is accumulating that the continuous exposure to high glucose concentrations during peritoneal dialysis (PD) is an important cause of ultrafiltration (UF) failure. The cornerstone of prevention and treatment of UF failure is reduction of glucose exposure, which will also alleviate the systemic impact of significant free glucose absorption. The challenge for the future is to discover new therapeutic strategies to enhance fluid and sodium removal while diminishing glucose load and exposure using combinations of available osmotic agents., Objectives: To investigate in patients on automated PD (APD) with a fast transport pattern whether there is a glucose-sparing advantage to replacing 7.5% icodextrin (ICO) during the long dwell with a mixed crystalloid and colloid PD fluid (bimodal UF) in an attempt to promote daytime UF and sodium removal while diminishing the glucose strength of the dialysate at night., Design: A 2 parallel arm, 4 month, prospective nonrandomized study., Setting: PD units or university hospitals in 4 French and Belgian districts., Results: During the 4-month intervention period, net UF and peritoneal sodium removal during the long dwell when treated by bimodal UF was about 2-fold higher than baseline (with ICO). The estimated percent change (95% confidence interval) from baseline in net daytime UF for the bimodal solution was 150% (106% - 193%), versus 18% (-7% - 43%) for ICO (p < 0.001). The estimated percent change from baseline in peritoneal sodium removal for the bimodal solution was 147% (112% - 183%), versus 23% (-2% - 48%) for ICO (p < 0.001). The estimated percent change from baseline in UF efficiency (24-hour net UF divided by the amount of glucose absorbed) was significantly higher (p < 0.001) when using the bimodal solution was 71%, versus -5% for ICO., Conclusion: Prescription of bimodal UF during the day in APD patients offers the opportunity to optimize the long dwell exchange in a complete 24-hour APD cycle. The current study demonstrated that a bimodal solution based on the mixing of glucose (2.6%) and icodextrin (6.8%) achieved the double target of significantly improving UF and peritoneal sodium removal by exploring a new concept of glucose-sparing PD therapy.

Objective: Serious discrepancies between glycemia measurements obtained with an Accutrend Sensor (Boehringer Mannheim GmbH, Mannheim, Germany) type analyzer (based on a glucose dehydrogenase enzymatic reaction) and measurements obtained in the laboratory by a reference method (hexokinase) have been found in an insulin-requiring, diabetic, continuous ambulatory peritoneal dialysis (CAPD) patient treated with icodextrin 7.5% (Extraneal; Baxter Healthcare SA, Castlebar, Ireland), a new osmotic agent for peritoneal dialysis. We therefore investigated the respective role of the Analyzer and of the glucose polymer in this hitherto undescribed problem., Design: Glycemia was measured simultaneously on venous blood using a reference laboratory technique, and on capillary blood using the Accutrend Sensor glucose analyzer in three groups of CAPD patients: 6 patients on Extraneal for at least 1 week, 6 patients receiving their first Extraneal exchange, and 8 patients never exposed to Extraneal. In the first group of patients, glycemia was also measured with another analyzer (Glucocard; Menarini Diagnostics, Firenze, Italy) using a different enzymatic reaction (glucose oxidase). In a separate study, whole blood of a normal subject was spiked with concentrated solutions of glucose and icodextrin and some of its metabolites (maltose, maltotriose, maltopentaose). Once again, comparative measurements of glycemia were performed with the Accutrend Sensor, with two other kits using a glucose dehydrogenase enzyme reaction, and with the hexokinase reference method., Results: In 6 CAPD patients treated with once-daily exchanges with Extraneal for a minimum of 7 consecutive days, we confirmed overestimation of glycemia by the Accutrend Sensor of 65 +/- 26 mg/dL compared to reference values (p < 0.01), and of 69 +/- 25 mg/dL (p < 0.001) compared to measurements obtained with the Glucocard monitor. In 6 other CAPD patients studied at the end of one single icodextrin exchange, overestimation of 61 +/- 11 mg/dL was already present (p < 0.001). On the other hand, in 8 CAPD patients never treated with icodextrin, there was no discrepancy between the Accutrend Sensor readings and reference values. The measurements in spiked blood confirmed that only the Accutrend Sensor overestimates glycemia in the presence of maltose and glucose polymers. The overestimation decreased as the molecular size of the saccharides added to blood increased. There was no overestimation when other kits using a dehydrogenase enzyme were tested., Conclusion: The overestimation observed is probably related to the presence of oligosaccharides (mainly maltose), derivatives of glucose polymers present in Extraneal and absorbed via the peritoneal route, in the blood of patients treated with icodextrin. The glucose dehydrogenase characterizing the Accutrend Sensor, an enzyme of the pyrroloquinolinequinone class, very likely reacts with the free reducing group of the glucose molecule located at the end of each saccharide chain. This would not be the case for the Glucocard monitor using glucose oxidase, for other kits using glucose dehydrogenase, and for the reference method based on hexokinase. The Accutrend Sensor type of analyzers are therefore not suitable for regular monitoring of glycemia in diabetic PD patients treated with icodextrin.