Markers of inflammation and oxidative stress in peritoneal dialysis: a comparison between high and low peritoneal...

High transport status is reported to be associated with increased mortality in peritoneal dialysis (PD). It has been hypothesized that this might be a result of a state of chronic inflammation and increased oxidative stress. We performed this pilot study to explore this hypothesis.

Based on the standard peritoneal equilibration test, PD patients were divided in two transporter groups: LOW (Low + Low average) and HIGH (High + High Average). Markers of inflammation and oxidative stress were compared between the two groups, including C-reactive protein (CRP), plasma apoptogenic potential, monocyte HLA DR expression, Advanced Oxidative Protein Products (AOPP) and reactive carbonyl residues (RCO).

Of 42 patients (34 male/8 female) studied, 8 patients were LOW and 34 were HIGH transporters. Median values of CRP (1.39 vs. 0.62 mg/L), plasma apoptogenic potential (15 vs. 14.5%), AOPP (118.36 vs. 113.86 micromol/L) and RCO (1.72 vs. 1.13 nmol/mg protein) were similar among LOW and HIGH transporters. However HIGH transporters had significantly lower monocyte HLA DR expression (mean fluorescent intensity (MFI) -197.89 vs. 124.98 units, p=0.02) compared with LOW transporters.

Stable chronic PD patients with high peritoneal transport status have reduced monocyte HLA-DR expression, a biomarker of increased risk for infections. This could potentially contribute to a higher risk of mortality in this group.