Randomized controlled trial of cephalexin versus clindamycin for uncomplicated pediatric skin infections

To compare clindamycin and cephalexin for treatment of uncomplicated skin and soft tissue infections (SSTIs) caused predominantly by community-associated (CA) methicillin-resistant Staphylococcus aureus (MRSA). We hypothesized that clindamycin would be superior to cephalexin (an antibiotic without MRSA activity) for treatment of these infections.

Patients aged 6 months to 18 years with uncomplicated SSTIs not requiring hospitalization were enrolled September 2006 through May 2009. Eligible patients were randomly assigned to 7 days of cephalexin or clindamycin; primary and secondary outcomes were clinical improvement at 48 to 72 hours and resolution at 7 days. Cultures were obtained and tested for antimicrobial susceptibilities, pulsed-field gel electrophoresis type, and Panton-Valentine leukocidin status.

Of 200 enrolled patients, 69% had MRSA cultured from wounds. Most MRSA were USA300 or subtypes, positive for Panton-Valentine leukocidin, and clindamycin susceptible, consistent with CA-MRSA. Spontaneous drainage occurred or a drainage procedure was performed in 97% of subjects. By 48 to 72 hours, 94% of subjects in the cephalexin arm and 97% in the clindamycin arm were improved (P = .50). By 7 days, all subjects were improved, with complete resolution in 97% in the cephalexin arm and 94% in the clindamycin arm (P = .33). Fevers and age less than 1 year, but not initial erythema > 5 cm, were associated with early treatment failures, regardless of antibiotic used.

There is no significant difference between cephalexin and clindamycin for treatment of uncomplicated pediatric SSTIs caused predominantly by CA-MRSA. Close follow-up and fastidious wound care of appropriately drained, uncomplicated SSTIs are likely more important than initial antibiotic choice.