Beta-lactams may be appropriate first-line treatment for pediatric skin infections in areas where MRSA is prevalent
Research Activities, November 2009
In many regions of the country, community-acquired methicillin-resistant Staphylococcus aureus (MRSA) is now the most commonly identified cause of skin and soft-tissue infections, such as impetigo, cellulitis, and small abscesses. Most of these infections are treated with antibiotics without actually determining if MRSA or another organism is indeed present. A new study concludes that beta-lactam therapy is an effective treatment for these infections among children living in areas where MRSA is prevalent, when the infectious agent is unknown. Researchers at the Center for Education and Research on Therapeutics (CERT) at the University of Pennsylvania School of Medicine looked at 2,096 children who were treated as outpatients for skin and soft-tissue infections, which were neither drained nor cultured at the initial visit. The children were selected from five pediatric practices in an urban area where MRSA was prevalent.
All were treated with one of three antibiotic agents: beta-lactams, clindamycin, or trimethroprim-sulfamethoxazole (TMP-SMX). After the antibiotic was given, 104 of the children (5 percent) were determined to have failed treatment, that is, they had to have a drainage procedure, were hospitalized, or had to change antibiotics or get a second antibiotic prescription within 28 days. Each child was then matched to 480 control patients who had been treated successfully. The use of clindamycin and TMP-SMX to treat community-acquired MRSA increased significantly from 16.4 percent in 2004 to 62.2 percent in 2007, while the use of beta-lactams decreased. In this study, TMP-SMX accounted for 19 percent of prescriptions, but was associated with double the treatment failure of beta-lactam therapy.
There was no difference in the risk of treatment failure between clindamycin and beta-lactam. Additional factors associated with an increase in treatment failure included white race, being seen first in the emergency department, antibiotic use within the previous 6 months, fever, and the presence of an induration or small abscess. This study was funded in part by a grant from the Agency for Healthcare Research and Quality (HS10399) to the University of Pennsylvania School of Medicine CERT. For more information on the CERT program, please visit www.certs.hhs.gov/index.html. See “Empiric antimicrobial therapy for pediatric skin and soft-tissue infections in the era of methicillin-resistant Staphylococcus aureus,” by Daniel J. Elliott, M.D., M.S.C.E., Theoklis E. Zaoutis, M.D., M.S.C.E., Andrea B. Troxel, Sc.D., and others, in the June 2009 Pediatrics 123(6), pp. e959-e966.