CDC Reports on MRSA Infections Among Patients on Dialysis

Staphylococcus aureus, a leading cause of bloodstream infections in the United States, has become increasingly resistant to first-line antimicrobial agents. Patients on dialysis are particularly susceptible to methicillin-resistant S. aureus (MRSA) infection.

Compared with the general population, in which MRSA infections occur in only 0.2 to 0.4 per 1,000 persons, patients on dialysis are at high risk of MRSA infection. The Centers for Disease Control and Prevention (CDC) estimates that invasive MRSA infections occurred in 45 out of 1,000 patients on dialysis in 2005; these results indicate a 100-fold higher risk of MRSA infection in these patients.

Patients on dialysis who are older than 50 years are at especially increased risk of infection. The CDC also found that men and blacks on dialysis are at increased risk; of the total number of patients on dialysis who had been infected with MRSA, 57 percent were men, and 56 percent were black.

Those patients on dialysis who have invasive devices or a catheter also are at increased risk; according to the CDC, in the event of infection, 90 percent of those patients required hospitalization, and the in-hospital mortality rate for MRSA was 17 percent. Although the risk of infection in patients with a catheter is high, the risk is intermediate for grafts and low for arteriovenous fistulas.

Physicians should use antimicrobials judiciously to reduce pathogens only after following published guidelines. This is particularly true of vancomycin, because cases of S. aureus resistance to this drug have been reported.