Plasma S100A12 Concentrations in Peritoneal Dialysis Patients and Subclinical Chronic Inflammatory Disease

:  S100A12 is a ligand for the receptor for advanced glycation end products. It has been shown that S100A12 induces expression of adhesion molecules, and mediates activation and migration of monocytes/macrophages. Circulating S100A12 may be involved in chronic inflammation. We previously reported increased S100A12 levels in patients with non-insulin-dependent diabetes mellitus and hemodialysis. A high peritoneal solute transport rate may be associated with encapsulating peritoneal sclerosis and mortality. We measured plasma S100A12 levels in peritoneal dialysis patients and evaluated a possible relation between the increased plasma S100A12 levels in peritoneal dialysis patients and the high peritoneal solute transport rate. Subjects included 36 patients (mean age ± SE, 46.0 ± 12.0 years) with no apparent infection and no malignancy who had been undergoing peritoneal dialysis for 36.5 ± 3.9 months. We developed an enzyme-linked immunosorbent assay system to measure plasma S100A12 levels. A peritoneal equilibrium test was performed and subjects were categorized as high and high-average (H) (n = 14) or low and low-average (L) (n = 22) transporters. Plasma S100A12 concentrations were significantly higher in peritoneal dialysis patients (21.6 ± 3.0 ng/mL) than in control subjects (n = 42; 10.8 ± 1.0 ng/mL). Plasma S100A12 concentrations were also higher in the H group (28.2 ± 6.1 ng/mL) than in the L group (14.2 ± 2.0 ng/mL). These results suggest that S100A12 may be a sensitive marker of subclinical inflammation and that an increased S100A12 level may be related to the high peritoneal solute transport rate.