Elimination of iomeprol in patients undergoing continuous ambulatory peritoneal dialysis

Objective:To examine the elimination of iomeprol, its safety in clinical use, and its peritoneal permeability in continuous ambulatory peritoneal dialysis (CAPD) patients with variable degrees of residual renal function (RRF). Design: A nonrandomized comparison study. Setting: Hospitalized patients in CAPD unit of Chikuho and University Hospitals. Participants: Fourteen patients treated by CAPD and 6 by hemodialysis (HD). Interventions:Total dialysate, blood, and 24-hour urine collections were obtained for 4 consecutive days after the administration of iomeprol. A peritoneal equilibration test was performed just before and after the administration of iomeprol. Measurements: Iomeprol (iodine) concentration was measured. Residual renal function was estimated as the mean of renal creatinine and urea clearances. Dialysate-to-plasma ratios (D/P) of creatinine and iomeprol were also determined. Results: In all CAPD patients, plasma iomeprol clearance was markedly slow, with a biological half-life (T-1/2) of over 32 hours. However, no patients suffered from any adverse effects, and over 80% of plasma iomeprol was eliminated during the 4-hour HD. The plasma iomeprol elimination rate was significantly higher from 4 hours after the iomeprol administration in CAPD patients with RRF [mean estimated creatinine clearance (CCr) 3.8 mL/min, n = 7] compared to the remaining patients (mean estimated CCr 0.6 mL/min, n = 7); however, T-1/2 in patients with RRF was over 24 hours. D/P creatinine was significantly correlated with Dip iomeprol, and peritoneal iomeprol permeability may depend on an individual's peritoneal solute transport properties. Conclusions: A prolonged elimination rate of iomeprol was documented in our CAPD patients both with and without RRF. A HD procedure or intensive peritoneal dialysis just after the use of iomeprol may be advisable to promptly remove circulating iomeprol.