Risk and Prognosis of Bacteremia and Fungemia among Peritoneal Dialysis Patients: A Population-Based Cohort Study

Abstract

Background The incidence of bacteremia and fungemia (BAF) is largely unknown in end-stage renal disease (ESRD) patients initiating peritoneal dialysis (PD). Objective The main objective was to estimate and compare incidence rates of first episodes of BAF in incident PD patients and a comparison cohort. A secondary objective was to compare causative agents and 30-day post-BAF mortality between PD patients and the comparison cohort. Methods Design: Observational cohort study. Setting: Central and North Denmark regions. Participants: patients who initiated PD during 1995 – 2010. For each patient we sampled up to 10 controls from the general population matched on age, sex, and municipality. Main outcome Data on positive blood cultures were retrieved from electronic microbiology databases covering the 2 regions. We calculated incidence rates (IRs) of first-time BAF for PD patients and population controls. Incidence-rate ratios (IRRs) were calculated to compare these rates. Thirty-day mortality was estimated by Kaplan-Meier analysis. Results Among 1,024 PD patients and 10,215 population controls, we identified 75 and 282 episodes of BAF, respectively. Incidence rates of BAF were 4.7 (95% confidence interval [CI], 3.8 – 5.9) per 100 person-years of follow-up (PYFU) in PD patients and 0.5 (95% CI, 0.4 – 0.5) per 100 PYFU in population controls (IRR = 10.4; 95% CI, 8.1 – 13.5). In PD patients, the most frequent microorganisms were Escherichia coli (18.7%) and Staphylococcus aureus (13.3%). Escherichia coli (27.3%) also ranked first among population controls. Thirty-day mortality following BAF was 20.8% (95% CI, 12.6 – 31.0) and 20.7% (95% CI, 16.3 – 25.9) among PD patients and population controls, respectively. Conclusions Peritoneal dialysis patients are at markedly higher risk of BAF than population controls. Causative agents and the 30-day post-BAF mortality were similar in the 2 cohorts.