NEW YORK (Reuters Health) – Treatment of skin and soft-tissue infections (SSTIs) in children in regions where community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) is prevalent is more likely to fail when trimethoprim-sulfamethoxazole or beta-lactams are used, rather than clindamycin, a study has shown.
“Our findings call into question the routine use of trimethoprim-sulfamethoxazole for purulent SSTIs in CA-MRSA–prevalent regions where clindamycin resistance remains low,” the researchers advise in the September issue of Pediatrics.
Dr. Derek J. Williams, with Vanderbilt University School of Medicine in Nashville, Tennessee, and colleagues point out that CA-MRSA is a growing problem and accounts for more than 70% of staph infections in some regions of the US. Beta-lactams used to be the most commonly used antibiotics for SSTIs but they are not effective against CA-MRSA. Currently, clindamycin and trimethoprim-sulfamethoxazole are among the most commonly recommended oral antibiotics for pediatric SSTIs.
To compare the effectiveness of clindamycin, trimethoprim-sulfamethoxazole and beta-lactams for SSTIs in children, the team examined data on 47,500 such children enrolled in the public health care plan in Tennessee in 2004-2007.
A subset of 6407 of the patients underwent drainage, mostly with a diagnosis of abscess/cellulitis. In this group, treatment failure occurred in 8.9%. The odds of failure doubled with trimethoprim-sulfamethoxazole (adjusted OR: 1.92) and beta-lactams (adjusted OR: 2.23) compared with clindamycin, the investigators found.
Among the other patients who did not have a drainage procedure, the failure rate was 5.9% and the adjusted odds ratios for failure were 1.67 for trimethoprim-sulfamethoxazole and 1.22 for beta-lactams, compared with clindamycin.
Recurrence rates were also higher with trimethoprim-sulfamethoxazole and beta-lactams. The respective hazard ratios for recurrence were 1.26 and 1.42 in the drainage group, while corresponding figures in the non-drainage group were 1.30 and 1.08. However, the latter was not statistically significant, according to the report.
Apart from the lesser effectiveness of trimethoprim-sulfamethoxazole, Dr. Williams and colleagues draw attention to other implications of the findings.
“Although beta-lactams are no longer recommended when MRSA is a consideration, these agents may still be effective for nonpurulent SSTIs such as uncomplicated cellulitis or impetigo,” they point out.
“Furthermore,” they add, “although incision and drainage remains the mainstay of treatment for purulent SSTIs, our data confirm that antimicrobial agents are used frequently after drainage, and they suggest, at least indirectly, a possible additive benefit of appropriate antimicrobial therapy.”
Reference:
Comparative Effectiveness of Antibiotic Treatment Strategies for Pediatric Skin and Soft-Tissue Infections
Pediatrics 2011;128.
