Role of folate antagonists in the treatment of methicillin-resistant Staphylococcus aureus infection.
Methicillin-resistant Staphylococcus aureus (MRSA) infection has reached epidemic proportions, and therapeutic options are limited because these strains are often multidrug resistant. However, the new strains of community-acquired MRSA show decreased resistance to trimethoprim-sulfamethoxazole. Clinical and experimental reports show a mixture of successes and failures with trimethoprim-sulfamethoxazole treatment. A reason for failure might be the amount of thymidine released from damaged host tissues and bacteria, a concept strengthened by the fact that S. aureus thermonuclease releases thymidine from DNA. Thus, success or failure with trimethoprim-sulfamethoxazole may well depend on the amount of tissue damage and organism burden, rather than acquisition of a resistance gene. Clinical trials and experimental animal studies show high failure rates, perhaps because of released thymidine. The use of trimethoprim-sulfamethoxazole for community-acquired MRSA infection should not be endorsed without further research.
Proctor
Richard A
RA
Department of Medical Microbiology/Immunology and Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA. rap@facstaff.wisc.edu
D000818:Animals; D000890:Anti-Infective Agents / Q000494:pharmacology / Q000627:therapeutic use*; D017714:Community-Acquired Infections / Q000188:drug therapy / Q000382:microbiology; D006801:Humans; D016106:Methicillin Resistance; D013203:Staphylococcal Infections / Q000188:drug therapy* / Q000382:microbiology*; D013211:Staphylococcus aureus / Q000187:drug effects*; D015662:Trimethoprim, Sulfamethoxazole Drug Combination / Q000494:pharmacology / Q000627:therapeutic use*
D000890:Anti-Infective Agents; D015662:Trimethoprim, Sulfamethoxazole Drug Combination