"Pulse" nasal mupirocin maintenance regimen in patients undergoing continuous ambulatory peritoneal dialysis

OBJECTIVE: To determine, among patients undergoing continuous ambulatory pe ritoneal dialysis (CAPD) who were Staphylococcus aureus nasal carriers, if periodic brief "pulses" of nasal mupirocin calcium ointment 2% after comple tion of a mupirocin eradication protocol would maintain these patients free of carriage. DESIGN: Noncomparative, nonblinded study with historical controls. SETTING: A county medical center. PATIENTS: Patients in a CAPD program during the period April 1996 to May 19 98. METHODS: All patients in the CAPD program had monthly nasal cultures for S aureus. After informed consent, S aureus nasal carriers were administered m upirocin to the nares twice a day for 5 days followed by nasal mupirocin tw ice monthly. Peritonitis and exit-site infection rates were monitored indep endently by CAPD nursing staff. Patients were monitored monthly for adverse effects of mupirocin and compliance with the maintenance regimen. RESULTS: Twenty-four patients in the CAPD program were enrolled in the stud y and had a median duration of follow-up of 8.5 months. Fifteen (63%) of th e 24 patients remained free of nasal carriage on follow-up cultures. Of the 9 patients with positive nasal cultures during the study, 8 had only one p ositive culture. There was no significant difference in the mean yearly per itonitis rate or S aureus peritonitis rate (January 1995-May 1998). However , there was a significant decrease in the mean yearly exit-site infection r ates both overall (from 8.8 episodes per 100 patients dialyzed per month in 1995 to 4.0 in 1998; P=.008) and due to S aureus (from 5.6 in 1995 to 0.9 in 1998; P=.03). Adverse effects of nasal mupirocin were mild overall; 1 pa tient was removed from the study due to an allergic reaction to mupirocin. CONCLUSIONS: Among CAPD patients who were S aureus nasal carriers, periodic brief treatment with nasal mupirocin after an initial eradication regimen kept them free of carriage, for the most part, with few adverse effects. Th e pulse mupirocin regimen offers simplicity and possibly better compliance, as well as minimizing exposure to this agent, thereby possibly reducing th e risk of resistance. Further studies are warranted to compare this regimen to other commonly used mupirocin maintenance regimens in dialysis patients .