A comparison of peritoneal dialysis-related infections in short- and long-term peritoneal dialysis patients.

OBJECTIVE

We hypothesized that the infection rates and organisms would differ in long-term peritoneal dialysis (PD) patients versus those who died or transferred to hemodialysis during the first 4 years on PD.

DESIGN

Data on PD-related infections and outcome were collected from 1979 to 1991 (prospectively since 1982).

SETTING

The patients were followed at University and Veterans Administration dialysis centers.

PATIENTS

All patients on continuous ambulatory peritoneal dialysis (CAPD) or continuous cycling peritoneal dialysis (CCPD) for 4 years or more (n = 43) were compared to those patients who died or transferred to hemodialysis prior to 4 years on PD (n = 213).

MAIN OUTCOME MEASURES

Infection rates due to various microorganisms and reasons for transfer to hemodialysis were examined.

RESULTS

Peritonitis rates were 1.2/year versus 0.8/year (p < 0.001) in patients on peritoneal dialysis less than 4 years compared to those on 4 years or more, respectively, a difference due to S. epidermidis (0.32/year vs 0.20/year, p = 0.0001) and gram-negative rods other than P. aeruginosa (0.15/year versus 0.06/year, p < 0.001). Exit-site infection rates were 1.2/year versus 0.7/y (p < 0.0001) in the patients on less than 4 years compared to those on 4 years or more, respectively, a difference in part due to S. aureus (0.45/year vs 0.3/year, p < 0.001) and other gram-positive organisms (0.28/year vs 0.10/year, p < 0.001). The rates of infections that were similar in the two groups were tunnel infections (0.2/year), P. aeruginosa infections, and S. aureus peritonitis (0.18/year vs 0.14/year, p = 0.09). S. aureus was the most common cause of exist-site and tunnel infections in both groups. Forty-two percent of the patients on PD 4 years or more subsequently transferred to hemodialysis, most often due to infections, especially S. aureus.

CONCLUSIONS

Although infection rates are lower in patients on peritoneal dialysis 4 years or more, S. aureus and P. aeruginosa continue to account for a high proportion of the infections. Improvement in technique survival will require prevention of these infections.