Antibiotic Combination Shown To Be Effective Against Resistant Bug
A team of researchers led by The Rockefeller University's Alexander Tomasz, Ph.D., have described the case of a 79-year-old patient whose death in a New York metropolitan area hospital last March was associated with a bloodstream infection caused by a multidrug-resistant strain of Staphylococcus aureus. The report, published in the Feb. 18 issue of the New England Journal of Medicine (NEJM), showed that the bacteria, which had decreased susceptibility to vancomycin, could be treated effectively with a combination of antibiotics.
"We think that this is the first demonstration that selection for strains with increased resistance to vancomycin can occur during therapy," says Tomasz, senior author of the paper and professor and head of the Laboratory of Microbiology.
The case described in the NEJM article was the fourth in the world associated with infections caused by multiresistant strains of Staphylococcus aureus (MRSA) that also show partial resistance to vancomycin, a drug often described as the "last resort" antibiotic against these dangerous pathogens that cause many hospital-acquired infections in the United States and elsewhere.
"The emergence of vancomycin-resistant Staphylococcus aureus strains emphasizes the importance vancomycin dosing to assure complete eradication of the bacteria", says Richard B. Roberts, M.D., a co-author of the report and an adjunct professor at Rockefeller and professor of medicine at New York Hospital-Cornell Medical Center.
A hopeful finding reported by the Rockefeller team is that a combination of two commonly used antibiotics, oxacillin and vancomycin, produced a synergistic effect and killed the vancomycin-resistant MRSA very efficiently in the test tube.
"If these results can be translated into the clinical setting, they suggest that
a combination of vancomycin and oxacillin may be an effective therapeutic
regimen against vanco
Contact: Joseph Bonner