A comparison of peritoneal dialysis-related infections in black and white patients

Objective: To determine if black patients in our peritoneal dialysis (PD) program had higher rates of PD-related infections. The outcomes of black patients versus white patients were also reviewed. Design: A review of prospectively collected patient demographic and PD-related infection data and outcomes, from 1979 to 1991. Patients: The 68 black patients in our PD program were matched with white control patients for age, sex, insulin dependence, time on dialysis, and mode of dialysis (CAPD or CCPD). The infection, demographic, and outcome data from the two groups were compared. Results: Black patients had higher peritonitis rates (1.10 vs 0.82 episodes/year, p=0.001) and exit-site infection rates (1.13 vs 0.95 episodes/year, p=0.02) than the white control patients. Tunnel infection rates were 0.21 episodes/year in both groups. S. epidermidis peritonitis was more common in black patients (48% of episodes vs 21% of episodes in whites, p=0.005), and S. aureus peritonitis was more common in white patients (29% vs 11% in blacks, p=0.005). The subset of black patients (n=13) on a disconnect system (Y-set) had a peritonitis rate similar to their white controls on the Y-set (0.41 vs 0.74 episodes/year, p=0.27). There were no episodes of S.epidermidis peritonitis in this subset of black patients. Black patients had fewer S. aureus exit-site infections than white patients (21% vs 41%, p=0.005). Peritonitis was the leading cause of transfer to hemodialysis in the black patients but not in the white patients. Conclusion: The susceptibility to S. aureus and S. epidermidis infections differs in black and white patients on peritoneal dialysis for unclear reasons. Peritonitis rates in black patients can be reduced to that of white patients if a disconnect system is used.