chapter  10
24 Pages

Antibiotics for MRSA Infections in the United States /

ByR. Lawrence Reed

Methicillin-resistant Staphylococcus aureus (MRSA) is a multidrug

resistant organism. Depending on the MRSA strain, antibiotic resistance

patterns have varied. All MRSA strains are, by definition, resistant to

methicillin and other b-lactam antibiotics. However, resistance to other antimicrobials is common, especially in the case of health care-associated

MRSA (HA-MRSA or USA100), which is usually resistant to amino-

glycosides and fluoroquinolones in addition to b-lactam antibiotics. Despite MRSA’s resistance to several antimicrobials, there is a

growing list of new agents that are effective against the organism. In

addition, community-acquired MRSA (CA-MRSA, or USA300) is often

sensitive to many traditional antibiotics, including minocycline, dox-

ycycline, trimethoprim/sulfamethoxazole, rifampin, and clindamycin.

HA-MRSA may occasionally be sensitive to these agents, but other

agents are usually necessary to insure effective therapy.