Decrease in Staphylococcus aureus exit-site infections and peritonitis in CAPD patients by local application of mupirocin ointment at the catheter exit site.

OBJECTIVE: To evaluate the potential effectiveness of the application of mupirocin ointment at the catheter exit site in preventing exit-site infection and peritonitis caused by Staphylococcus aureus (SA).

DESIGN: This prospective, historically controlled study was done on 181 peritoneal dialysis patients treated between 1 November 1996 and 1 November 1997. They were instructed to apply mupirocin at the catheter exit site daily or three times per week at the conclusion of their exit-site care (Study 1). The patients were not screened to determine whether they were SA carriers. The group's historical control was the infection data from the previous year among these patients. A second group of 70 patients, who started using mupirocin within a month after catheter implantation (1996-1997), was compared with a historical group of 118 patients (controls) who were on continuous ambulatory peritoneal dialysis (CAPD) for 1 year after in-patient implantation without mupirocin, (1990-1995) (Study 2).

RESULTS: In the group of 181 patients (Study 1), application of mupirocin at the exit site led to a significant reduction in SA exit-site infections--21 versus 3 episodes (0.11 vs 0.01 episodes/patient/year)--and a significant reduction of SA peritonitis--35 episodes in the year preceding mupirocin versus 11 episodes during the year of mupirocin treatment (0.19 vs 0.06 ep/pt/yr). The same results were observed in Study 2: the incidence of SA exit-site infection was significantly lower in the mupirocin-treated group--17 episodes among the 118 nontreated patients versus 4 episodes among 70 patients using mupirocin (0.14 ep/pt/yr vs 0.06 ep/pt/yr, respectively). Similarly there were 20 episodes of SA peritonitis among 118 patients during their first year of CAPD versus 4 episodes in 70 mupirocin-treated patients (0.16 ep/pt/yr vs 0.06 ep/pt/yr, respectively). No adverse effects were observed among the patients treated with mupirocin. Overall peritonitis rates decreased from 0.87 to 0.48 ep/pt/yr (p < 0.01) in Study 1 and from 0.56 to 0.41 ep/pt/yr (p = NS) in Study 2. We observed no differences in the incidence of exit-site infection and peritonitis rates among patients applying mupirocin ointment at the exit site daily, compared to three times per week.

CONCLUSIONS: Mupirocin application at the exit site significantly lowers the incidence of SA exit-site infections and peritonitis due to SA infections. Since SA infections are accompanied by significant morbidity and occasional mortality, this treatment may improve long-term survival of patients on CAPD.