Diagnostic and prognostic significance of procalcitonin and endotoxin in peritoneal dialysis-related peritonitis

Objective: To identify potential markers for detecting and monitoring inflammation in patients with peritoneal dialysis (PD)-related peritonitis, several inflammation markers, including procalcitonin (PCT), endotoxin and C-reactive protein (CRP), were evaluated in patients with PD-related peritonitis. Methods and Results: In this study, 50 cases of patients with PD-related peritonitis were recruited during 2011-2014, and 50 patients who had continuous ambulatory peritoneal dialysis but did not develop any infection were included as the control group. Serum samples were first collected to compare basal levels of PCT, endotoxin and CRP between PD-related peritonitis patients and control group. Then a prospective study was developed in PD-related peritonitis patients to compare the levels of PCT, endotoxin and CRP before and 2 weeks after antibiotic treatments. Meanwhile, PD fluid samples were collected for dialysate nucleated cell counts and the culture of effluent. Our results showed that levels of hemoglobin and serum albumin were significantly decreased while PCT, endotoxin, CRP and dialysate nucleated cell counts were elevated in patients with PD-related peritonitis, compared to the control group. After antibiotic treatment, levels of serum PCT, endotoxin and CRP were significantly decreased compared to basal levels in patients with PD-related peritonitis. Thirty-five cases (70%) of patients with PD-related peritonitis yielded positive results of bacterial culture, among which 21 cases (60% of 35 cases) were identified to be Gram-positive bacteria, 12 cases (34.26% of 35 cases) were Gram-negative bacteria and 2 cases (5.71%) were fungi. Importantly, in PD-related peritonitis patients, patients with positive bacterial culture showed greater levels of PCT and endotoxin, compared to patients with negative bacterial culture. Conclusions: Our results supported that serum PCT and endotoxins may be useful markers for monitoring inflammatory status and predicting responses to antibiotic treatment in PD-related peritonitis.