Inflammatory factors for hypoalbuminemia in Japanese peritoneal dialysis patients

Hypoalbuminaemia is a common complication of peritoneal dialysis (PD), and the leakage of albumin through peritoneal membrane may be a principal reason for hypoalbuminaemia. However, the relationship between peritoneal inflammation, peritoneal transport properties and hypoalbuminaemia has not been fully elucidated.

A cross-sectional study was performed on 76 Japanese PD patients who had been using a low-glucose PD solution and icodextrin. Systemic inflammatory markers of C-reactive protein (CRP) and serum interleukin-6 (IL-6), peritoneal effluent markers of dialysate IL-6 and CA125, the dialysate-to-plasma ratio of creatinine (D/Pcr) and the dialysate protein concentration were measured and examined for their relationship with hypoalbuminaemia.

There was a significant positive correlation between serum IL-6 and dialysate IL-6, mean dialysate IL-6 being significantly higher than mean serum IL-6, suggesting that intraperitoneal inflammation was a principal origin of systemic inflammation. Both serum and dialysate IL-6 were significantly correlated with serum albumin (r= -0.25, P<0.05 and r=-0.32, P<0.01, respectively). Dialysate IL-6 was significantly correlated with D/Pcr and the dialysate protein concentration, and there was a significantly positive association between D/Pcr and the dialysate protein concentration. Dialysate CA125, which is argued to be a marker of mesothelial cell mass in this study, was positively correlated with D/Pcr and the dialysate protein concentration. The dialysate protein, dialysate IL-6 and dialysate CA125 all increased according to the peritoneal transport rate defined by D/Pcr. A multiple-regression analysis showed that serum albumin was independently associated with the age, D/Pcr and serum IL-6.

Hypoalbuminaemia was attributable to both the increased peritoneal permeability and systemic inflammation, and intraperitoneal inflammation might contribute to developing these complications.