Abstract:  Methods A total of 432 episodes of peritonitis between Jan. 2008 and Apr. 2014 were prospectively analyzed. According to the characteristics of the second-episode peritonitis, the episodes were divided into relapse/repeat group and control group. Baseline clinical characteristics, pathogenic bacteria and outcomes were compared between the two groups. Results Most relapse/repeat peritonitis were caused by coagulase negative staphylococcus species especially by epidermis staphylococcus, accounting for 66.7% episodes in relapse/repeat group but for 29.5% episodes in control group (P ＜0.001). Analyses of the short-term and long-term outcomes showed that the risk for developing subsequent peritonitis was higher in relapse/repeat group than in control group (20.8% vs. 1.7 %, P=0.001 for short-term outcome; 37.5% vs. 15.3 %, P=0.008 for long-term outcome), but the mortality rate, the ratio of patients changed to hemodialysis, and the ratio of patients remaining on peritoneal dialysis were similar between the two groups.  Conclusions Coagulase negative staphylococcus especially staphylococcus epidermidis was the most important pathogen in relapse/repeated peritonitis. More attention should be paid to the relapse/repeat peritonitis patients, who were at the high risk for developing subsequent peritonitis.

Key words: Peritoneal dialysis, peritonitis, Relapse, Repeat