Relationship between double-cuff versus single-cuff peritoneal dialysis catheters and risk of peritonitis.

BACKGROUND Peritonitis among peritoneal dialysis (PD) patients remains an important complication. To date, no catheter type has consistently been shown to reduce peritonitis risk. It has been hypothesized that double-cuff catheters might be superior to single-cuff catheters in preventing peritonitis caused by periluminal entry of organisms. METHODS Using data collected in the multicentre Canadian Baxter Peritonitis Organism Exit-Sites Tunnel Infections (POET) database between 1996 and 2005, the association between number of catheter cuffs and peritonitis was tested. Variables adjusted for in the negative binomial model included age, gender, race, diabetes, renal disease, transfer from haemodialysis, previous renal transplant, PD modality and swan neck versus straight catheter. RESULTS Data were available for 4247 incident patients with a total of 2555 peritonitis episodes, corresponding to a peritonitis rate of 0.364 per dialysis year at risk. After adjustment for covariates, double-cuff catheter use was associated with a trend towards a lower peritonitis rate ratio (RR) 0.90, 95% confidence interval (CI) 0.80-1.01, P = 0.08]. This trend was largely due to a decreased Staphylococcus aureus peritonitis rate in those with a double-cuff catheter (RR 0.46, 95% CI 0.33-0.64, P < 0.001). When stratified by era of PD initiation, the benefit of double-cuff catheters was seen only among those initiating PD before 2001. CONCLUSION Use of a double-cuff PD catheter is associated with a reduction in S. aureus peritonitis. Loss of the association between cuff number and peritonitis after the year 2000 may relate to changes in exit-site care that reduce the bacterial burden available for periluminal migration.