The addition of a second antibiotic to treat cellulitis skin infections did not result in significantly better cure rates in research recently published in JAMA, the Journal of the American Medical Association.
The study was the latest from an emergency medicine research group that includes Truman Medical Centers and Mark T. Steele, M.D. ’80. Steele is associate dean for TMC Programs at the UMKC School of Medicine and chief medical officer and chief operating officer for Truman Medical Centers.
“I’ve been involved with this group for more than 20 years,” Steele said. “It has 11 sites across the country and studies infectious diseases relevant to emergency medicine. This latest study used five of those sites, including Truman.”
The study involved 500 patients who had cellulitis that was not accompanied by abscess or a wound. Half of those patients were treated with cephalexin, an antibiotic effective against streptococci that typically is used in such cases. The other half got cephalexin plus trimethoprim-sulfamethoxazole, an anti-staph antibiotic that more patients with skin and soft-tissue infections have been receiving “just in case” MRSA — methicillin resistant Staphylococcus aureus — is present.
For the entire group treated, the added antibiotic seemed to help, producing a cure rate of 76.2 percent, versus a 69 percent cure rate for those who received just cephalexin. But that difference was not considered statistically significant. In addition, when the results were narrowed to the patients who were known to have taken at least 75 percent of the recommended doses of their antibiotics, the cure rates were almost identical, 83.5 percent for those who also got the second antibiotic, and 85.5 percent those who received just cephalexin.
MRSA has been showing up as a cause of more severe, abscessed skin infections, which has led to more dual prescribing of the antibiotics. Steele said this study’s results could inform emergency physicians that for cellulitis, absent abscess or a wound, the addition of the second antibiotic wasn’t more effective.
Amy Stubbs, M.D., helped oversee Truman’s portion of the research. She’s an assistant professor of emergency medicine at the School of Medicine and director of the school’s emergency medicine residency program. She completed her residency in emergency medicine at UMKC and was chief resident.
The National Institutes of Health sponsored the study, which Steele said was particularly well constructed to meet the standards of JAMA, the world’s most widely circulated medical journal.
It was the third in a series of published studies by the emergency research group, called the EMERGEncy ID NET. One dealt with treatment of abscesses and was published in the New England Journal of Medicine. Another looked at infected wounds seen by emergency physicians and was published in the journal Clinical Infectious Diseases.