Vancomycin Therapy for Methicillin-Resistant Staphylococcus aureus

Abstract

Ten patients with bacteremia due to methicillin-resistant Staphylococcus aureus were treated with vancomycin. These patients were compared with matched controls, nine bacteremic patients with methicillin-sensitive S. aureus, and one patient with penicillin-sensitive S. aureus. Controls were treated with a penicillin. There were no significant differences in time to defervescence, metastatic infections, relapse, mortality, need for surgical drainage, or duration of therapy. Fifteen of 19 episodes of serious methicillin-resistant S. aureus infection responded to vancomycin. Severe toxic effects included tinnitus, neutropenia, rash, and possible nephrotoxicity. Tolerance (a minimal bactericidal concentration to minimal inhibitory concentration ratio of at least 32), but not a minimal bactericidal concentration of at least 32 mg/L, correlated with therapeutic failure (respectively, p = 0.04 and p = 0.11, Fisher's exact test). Bacteremic infections due to methicillin-resistant and methicillin-sensitive S. aureus cause similar morbidity and mortality. Vancomycin is effective but potentially toxic therapy for most serious infections due to methicillin-resistant S. aureus. In-vitro tests may not predict therapeutic efficacy.

Comparative evaluation of daptomycin (LY146032) and vancomycin in the treatment of experimental methicillin-resistant Staphylococcus aureus osteomyelitis in rabbits

“…With the increase in MRSA colonization and infection now being seen, the incidence of MRSA osteomyelitis can be expected to rise. Currently, vancomycin is the only reliable parenteral antibiotic for the treatment of MRSA infections, including osteomyelitis (16,17). However, longterm vancomycin therapy may cause nephrotoxicity and ototoxicity, especially when combined with an aminoglycoside (16).…”

“…MRSA has been isolated from cases of osteomyelitis (8)(9)(10)(11)(16)(17)(18). With the increase in MRSA colonization and infection now being seen, the incidence of MRSA osteomyelitis can be expected to rise.…”

“…Methicillin-resistant Staphylococcus aureus (MRSA) causes a variety of infections, including osteomyelitis (8)(9)(10)(11)(16)(17)(18). Heretofore, vancomycin has been the only reliable antibiotic available for treating MRSA infections (16,17).…”

“…Heretofore, vancomycin has been the only reliable antibiotic available for treating MRSA infections (16,17). However, long-term vancomycin therapy, especially in combination with the aminoglycosides, may cause nephrotoxicity and ototoxicity (16).…”

In vitro activity of two old antibiotics against clinical isolates of methicillin-resistant Staphylococcus aureus

“…6 However, other possibilities should be explored for those patients unable to tolerate the use of this drug or in the case of development of resistance to vancomycin among the strains of MRSA. 7 In recent years, new antistaphylococcal antibiotics, such as linezolid, daptomycin, tygecicline or telavancin, have been developed, but their cost is high. The infections caused by MRSA are serious and are difficult to treat.…”