POS-638 EFFLUENT DcR2 IS A NOVEL BIOMARKER FOR PERITONEAL FIBROSIS IN PERITONEAL DIALYSIS PATIENTS

Abstract

Peritoneal fibrosis is the most severe complication of peritoneal dialysis (PD), but lack of noninvasive biomarkers for monitoring the rate of progression of peritoneal fibrosis. Decoy receptor 2(DcR2), a marker of senescence, has been used to evaluate the degree of differentiation of tumors. The aim of this study is to determine whether peritoneal effluent DcR2 could serve as a novel specific and sensitive biomarker for assessing peritoneal fibrosis. 149 PD patients (PD duration>6 months) were enrolled in our unit from 2008 to 2018, free from acute infection and recent peritonitis. The fibrosis of peritoneal biopsy tissues were detected by Masson trichrome staining. Effluent and serum DcR2 levels were measured by ELISA and effluent appearance rate (AR) were calculated. The association of DcR2-AR with clinical parameters were analyzed. Receiver operating characteristics (ROC) curve analyzed area under the curve (AUC) of AR DcR2 for assessing peritoneal fibrosis. Double staining was undertaken for DcR2 with peritoneal mesothelial cells and fibroblast marker vimentin and fibrotic markers α-SMA and FN. There were 75 patients with peritoneal fibrosis and 74 without. Effluent and serum DcR2 levels had no statistical difference between two groups, but DcR2-AR levels were higher in patients with peritoneal fibrosis compared with normal peritoneum. Effluent DcR2-AR levels were associated with Duration of PD, total glucose exposure, past peritonitis (%) and 4h D/P. The area of under curve was 0.74 for peritoneal fibrosis, with a sensitivity of 73% and specificity of 76%, respectively. DcR2 was co-expressed with vimentin and colocalized with α-SMA and FN in peritoneal tissue. Effluent DcR2 can could potentially serve as a novel biomarker for peritoneal fibrosis and may reflect senescence of fibroblasts in PD patients.