CCL18 in peritoneal dialysis patients and encapsulating peritoneal sclerosis

P>Background Peritoneal fibrosis manifests clinically as membrane failure or encapsulating peritoneal sclerosis (EPS). There are no clinical or biochemical tests to determine the rate of progression of peritoneal fibrosis. CCL18/pulmonary and activation-regulated chemokine (PARC) is profibrotic and stimulates collagen production independent of the effect of transforming growth factor beta. This has not been studied in peritoneal dialysis (PD) patients. Materials and methods We have prospectively studied 106 patients, free from infection/recent peritonitis. A high concentration of CCL18 was discovered by multiplex antibody arrays and quantified by ELISA. Serum and dialysate levels were examined for their prognostic values. Results By multiple regression analysis, dialysate CCL18 (6 center dot 76 +/- 0 center dot 66 mu g 4 h-1) correlated with increasing membrane transport status (TS) (P < 0 center dot 0001) and total glucose exposure/24 h (P = 0 center dot 033). Serum CCL18 correlated with high TS (P = 0 center dot 0001) and duration of PD (P = 0 center dot 001). After 12 months of follow-up, 57 patients remained on PD while 12 patients were transferred to haemodialysis (HD) and seven developed EPS. Patients who subsequently developed EPS had higher baseline dialysate CCL18 (11 center dot 5 +/- 3 center dot 6 mu g 4 h-1 vs. 5 center dot 6 +/- 0 center dot 82 mu g 4 h-1, P = 0 center dot 03) and serum CCL18 (156 center dot 9 +/- 12 center dot 8 ng mL-1 vs. 124 center dot 8 +/- 12 center dot 2 ng mL-1, P = 0 center dot 02) compared with the stable PD group. Conclusion This is the first report of high levels of CCL18 in the spent dialysate and serum from long-term PD patients. These levels correlated with dysfunction of peritoneal membrane transport status, therefore following CCL18 in a longitudinal study may be of interest.