Differential Removal of Guanidinosuccinic Acid and Creatine by Hemodialysis and Continuous Ambulatory Peritoneal Dialysis

Abstract

Dear Sir,In two previous reports, we presented serum guanidino compound (GC) levels and the clearances of GCs by continuous ambulatory peritoneal dialysis (CAPD) and the influence of a single hemodialysis (HD) on serum GC levels in steady-state patients with terminal renal insuffi ciency (I, 2). Highly standardized dialysis procedures were performed. In hemodialyzed patients, guanidino succinic acid, among other GCs, remained markedly elevated and reached toxic levels before a dialysis ses sion. In serum of patients who underwent CAPD, guani dinosuccinic acid, creatinine and methylguanidine reached levels associated with toxic effects in vitro. Se rum creatine levels were lower in peritoneally dialyzed patients than in control subjects. In the peritoneal dialy sis group, significantly different clearances were found for the different GCs ranging from 4.02 ± 1.08 m l/m in for arginine to 7.94±2.76 ml/min for creatine during a 3-hour exchange period. Also in the hemodialyzed group, substantial differences were found in the percent decrease of the different GCs, ranging from 25 ± 13% for arginine to 74±7.5% for guanidinosuccinic acid.Here, we assessed the interrelationships of parameters for the removal of the GCs and urea by HD [2] and by CAPD[1] by calculating the linear correlation coefficient. The GCs considered were: arginine, homoarginine, N-aacetylarginine, guanidine, guanidinoacetic acid, creati nine, methylguanidine, argininic acid, guanidinosuccinic acid and creatine. The 3-hour equilibration percentage and the ratio (serum GC concentration before HD /serum GC concentration after HD) were used as para meters for the removal of ten different GCs and urea by CAPD and HD respectively. A weak, nonsignificant pos itive correlation ( r = 0.105) was found between CAPD equilibrium percentage and the parameter for GC remo val by HD ( fig.

Reviews: Uremic Toxins: A New Focus on an Old Subject

“…Despite dialytic interventions, however, levels remain increased compared with controls. A differential removal of GSA and CTN by HD and continuous CAPD has been shown (29).…”

“…Evidence of inflammation (C‐reactive protein [CRP]) correlates with evidence of oxidative stress and predicts increased mortality (26), cardiac hypertrophy, and a proatherogenic state (27,28). Recent interest has focused on IL‐6 as a marker for mortality (29–31) and carotid atherosclerosis (32–34).…”