Icodextrin and Intraperitoneal Inflammation

⋄ Background The peritoneum is impaired by exposure to biocompatible dialysis solutions. Because icodextrin peritoneal dialysis fluid (PDF) is made from cornstarch, a possibility that it induces intraperitoneal inflammation has been reported. In the present study, patients on glucose PDF were switched to icodextrin PDF and then switched back to glucose PDF. Icodextrin PDF-induced intraperitoneal inflammation was investigated based on changes in peritoneal permeability and inflammatory reactions. ⋄ Patients and Methods The subjects were 7 stable peritoneal dialysis patients (4 men, 3 women), with a mean age of 59.1 ± 3.8 years (range: 55.2 - 64.6 years). The mean duration of peritoneal dialysis was 58.3 ± 27.4 months (range: 34.3 - 97.7 months), and the cause of end-stage renal disease was chronic glomerulonephritis in all patients. For the overnight dwell, glucose PDF was changed to icodextrin PDF, and the patients returned to glucose PDF 30 months later. To evaluate peritoneal permeability, a peritoneal equilibrium test (PET) was performed, and dialysate-to-plasma (D/P) ratios of creatinine (Cr), β 2 -microglobulin (β2M), albumin, immunoglobulin G (IgG), and α 2 -macroglobulin (α2M) were measured in the overnight dialysate and serum. As markers of inflammation and fibrinolysis or coagulation, interleukin-6 (IL-6) and fibrinogen degradation products (FDPs) were measured in overnight effluent. The evaluations were made every 6 months for 36 months. ⋄ Results A significant elevation in FDP levels was detected in overnight effluent 6 months after the switch to icodextrin PDF, and IL-6 levels tended to increase. The D/P ratios of Cr, β2M, and albumin were also significantly increased, and the D/P ratios of IgG and α2M tended to increase. The D/P ratio of Cr as measured by PET was slightly increased, but the elevation was not significant. In 5 patients, after icodextrin PDF was switched back to glucose PDF at 30 months, the D/P ratios of Cr, β2M, albumin, IgG, and α2M in overnight effluent were significantly reduced. The FDP levels decreased slightly in those patients. In the remaining 2 patients, the D/P ratios of Cr on PET and of Cr, β2M, albumin, IgG, and α2M in overnight effluent, and the FDP and IL-6 levels in overnight effluent were markedly elevated after the switching from glucose to icodextrin PDF, and they remained high after the switch back to glucose PDF. One of these 2 patients developed pre-EPS and was treated with prednisolone and concomitant hemodialysis. The other was switched from peritoneal dialysis to hemodialysis. ⋄ Conclusions Icodextrin dialysis solution may induce an inflammatory reaction in the peritoneum. Further investigation is necessary for the long-term use of icodextrin PDF.