Methicillin-resistant staphylococcal infections in an outpatient peritoneal dialysis program.

In view of the increasing concern about hospital-acquired methicillin resistance, we examined the sensitivities and outcome of staphylococcal infections related to outpatient peritoneal dialysis over a 5-year period. Data on all episodes of peritonitis (n = 360) and catheter infections (n = 507) were gathered prospectively from January 1984 to December 1988. The numbers of patients on peritoneal dialysis each year ranged from 136 in 1984 to 109 in 1987. Fifteen methicillin-resistant staphylococcal infections (MRSI) related to outpatient peritoneal dialysis occurred. Three were due to methicillin-resistant Staphylococcus aureus found in infected exit sites (2.3% of all S aureus catheter infections). Two of these infections occurred in a continuous ambulatory peritoneal dialysis (CAPD) patient who carried methicillin-resistant S aureus in his nares. The other 12 methicillin-resistant organisms were coagulase-negative staphylococci that caused peritonitis. There was a significant increase in the percentage of episodes of coagulase-negative staphylococci peritonitis caused by methicillin-resistant organisms; from 5% (3/57) in 1984 through 1986 to 28% (9/32) in 1987 through 1988 (P less than 0.005). In view of the high percentage of coagulase-negative staphylococci peritonitis that is methicillin-resistant, vancomycin rather than cephalosporins should be used for initial treatment.