Increasing Antibiotic Resistance among Methicillin-Resistant Staphylococcus aureus Strains

G Sakoulas, RC Moellering Jr - Clinical infectious diseases, 2008 - academic.oup.com
G Sakoulas, RC Moellering Jr
Clinical infectious diseases, 2008academic.oup.com
Vancomycin use has increased dramatically worldwide since the mid-1980s, largely as a
result of empirical and directed therapy against burgeoning methicillin-resistant
Staphylococcus aureus (MRSA) infections. With limited choices, clinicians have traditionally
relied on vancomycin alone in the management of serious MRSA infections and have
enjoyed a significant period free of vancomycin resistance in S. aureus. Even now, 5
decades after its introduction, vancomycin resistance among S. aureus strains, as currently …
Abstract
Vancomycin use has increased dramatically worldwide since the mid-1980s, largely as a result of empirical and directed therapy against burgeoning methicillin-resistant Staphylococcus aureus (MRSA) infections. With limited choices, clinicians have traditionally relied on vancomycin alone in the management of serious MRSA infections and have enjoyed a significant period free of vancomycin resistance in S. aureus. Even now, 5 decades after its introduction, vancomycin resistance among S. aureus strains, as currently defined microbiologically, remains rare. Yet it is becoming clear that vancomycin is losing potency against S. aureus, including MRSA. Serious infections due to MRSA defined as susceptible in the laboratory are not responding well to vancomycin. This is demonstrated by increased mortality seen in patients with MRSA infection and markedly attenuated vancomycin efficacy caused by vancomycin heteroresistance in S. aureus. Therefore, it appears that our definition of vancomycin susceptibility requires further scrutiny as applied to serious MRSA infections, such as bacteremia and pneumonia.
Oxford University Press