Correspondence

Vancomycin Resistance in Staphylococcus aureus

N Engl J Med 1999; 341:207-208July 15, 1999

Article

To the Editor:

The first patient described by Smith et al. (Feb. 18 issue)1 had five bouts of peritonitis with methicillin-resistant Staphylococcus aureus. All were treated with intravenous vancomycin. The patient's peritoneal catheter remained in place. The catheter was not removed even when intermediate glycopeptide resistance developed in the patient's S. aureus isolate and therapy with combined intravenous and intraperitoneal vancomycin failed. The accompanying editorial2 points out that in an animal model, the presence of prosthetic material led to increased resistance in S. aureus to all antibiotics tested.3 In the patient described by Smith et al., the peritoneal catheter probably had a role in the recurrence of the peritoneal infection and in the eventual development of infection with glycopeptide-intermediate S. aureus. If methicillin-resistant S. aureus in association with prosthetic material does not respond rapidly to treatment with intravenous antibiotics or if the infection recurs, the prosthetic material should be removed if possible. Removal of chronically infected foci, rather than repeated treatment with intravenous antibiotics, will be crucial in the prevention of further vancomycin resistance in S. aureus.

Chandy C. John, M.D.
Rainbow Babies and Children's Hospital, Cleveland, OH 44106

3 References

1. 1

   Smith TL, Pearson ML, Wilcox KR, et al. Emergence of vancomycin resistance in Staphylococcus aureus. N Engl J Med 1998;340:493-501
   Full Text | Web of Science

2. 2

   Waldvogel FA. New resistance in Staphylococcus aureus. N Engl J Med 1998;340:556-557
   Full Text | Web of Science

3. 3

   Chuard C, Vaudaux P, Waldvogel FA, Lew DP. Susceptibility of Staphylococcus aureus growing on fibronectin-coated surfaces to bactericidal antibiotics. Antimicrob Agents Chemother 1993;37:625-632
   Web of Science | Medline

Author/Editor Response

The authors reply:

To the Editor: We agree that when involved in an infection, foreign bodies should be removed as soon as clinically possible. Although experience with glycopeptide-intermediate S. aureus is limited, the clinical courses in the first documented cases highlight the importance of adhering to certain basic tenets when treating infections — namely, the removal of foreign bodies and drainage of abscesses. In one patient, the initial methicillin-resistant S. aureus infection required three weeks of therapy with arbekacin and ampicillin–sulbactam but was successfully treated only after abscess drainage.1 A second patient had recurrent methicillin-resistant S. aureus infections while a peritoneal catheter was in place and required a total of 25 weeks of antimicrobial therapy. When the peritoneal catheter was removed, the infection did not recur.2 In a third patient, persistent infection and the development of glycopeptide-intermediate S. aureus occurred in a patient with an arteriovenous graft that had not been removed after methicillin-resistant S. aureus bacteremia developed.2 The presence of a foreign body cannot explain the recurrent bloodstream infections with methicillin-resistant S. aureus in a fourth patient, who had received 18 weeks of intermittent vancomycin therapy before glycopeptide-intermediate S. aureus infection developed.3 The repeated courses of antimicrobial agents, particularly vancomycin, in these patients parallel those in the in vitro S. aureus studies done by Sieradzki and Tomasz,4 in which repeated exposure to antimicrobials led to the selection of resistant S. aureus subpopulations. The presence of a foreign body may also augment resistance.5

In addition to draining abscesses and removing foreign bodies, it is important to maintain therapeutic levels of the most potent narrow-spectrum antimicrobial agent, according to the organism's antimicrobial-susceptibility profile, for a sufficient length of time. Clinicians should adhere to these basic and well-documented tenets for treating infections; failure to do so can result in difficulty eradicating the infection and consequently prolong antimicrobial therapy. Such prolonged use of antimicrobials can result in the emergence of resistant pathogens, such as glycopeptide-intermediate S. aureus.

Theresa L. Smith, M.D.
Michele L. Pearson, M.D.
William R. Jarvis, M.D.
Centers for Disease Control and Prevention, Atlanta, GA 30333

5 References

1. 1

   Hiramatsu K, Hanaki H, Ino T, Yabuta K, Oguri T, Tenover FC. Methicillin-resistant Staphylococcus aureus clinical strain with reduced vancomycin susceptibility. J Antimicrob Chemother 1997;40:135-136
   CrossRef | Web of Science | Medline

2. 2

   Sieradzki K, Roberts RB, Haber SW, Tomasz A. The development of vancomycin resistance in a patient with methicillin-resistant Staphylococcus aureus infection. N Engl J Med 1999;340:517-523
   Full Text | Web of Science | Medline

3. 3

   Smith TL, Pearson ML, Wilcox KR, et al. Emergence of vancomycin resistance in Staphylococcus aureus. N Engl J Med 1999;340:493-501
   Full Text | Web of Science | Medline

4. 4

   Sieradzki K, Tomasz A. Inhibition of cell wall turnover and autolysis by vancomycin in a highly vancomycin-resistant mutant of Staphylococcus aureus. J Bacteriol 1997;179:2557-2566
   Web of Science | Medline

5. 5

   Chuard C, Vaudaux P, Waldvogel FA, Lew DP. Susceptibility of Staphylococcus aureus growing on fibronectin-coated surfaces to bactericidal antibiotics. Antimicrob Agents Chemother 1993;37:625-632
   Web of Science | Medline