Empiric antibiotic therapy with clindamycin resulted in fewer recurrences and treatment failures among children with skin and soft tissue infection (SSTI) than trimethroprim-sulfamethoxazole (TMP-SMX) or beta-lactams, data from a retrospective cohort study indicate.
With the emergence of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA), more pediatricians are perplexed when considering how best to treat SSTIs, given the lack of available data. Currently there are no published, large-scale, randomized trials of antimicrobials for SSTIs in children.
To compare the effectiveness of different antibiotic regimens, Derek J. Williams, MD, MPH, of Vanderbilt University School of Medicine in Nashville, and colleagues, analyzed SSTI outcomes among 47,501 children enrolled in Tennessee’s Medicaid program who had an incident skin or soft tissue infection between Jan. 1, 2004, and Dec. 31, 2007.
The retrospective analysis compared treatment failure and recurrence rates among children treated with one of three antibiotics — clindamycin (n= 7,459), TMP-SMX (n=10,623) or beta-lactams (n=29,419).
Treatment failure was defined as a renewed infection within 14 days, and recurrence was defined as a new infection within 14 to 365 days. The researchers performed separate analyses for those who underwent incision and drainage and those who did not.
Among the 6,407 children who underwent a drainage procedure, the researchers determined the following:
Treatment failure occurred in 107 clindamycin patients, compared with 246 taking TMP-SMX and 215 taking a beta-lactam
- Compared with clindamycin, prescribing TMP-SMX (OR=1.67; 95% CI: 1.44-1.95) or a beta-lactam (OR= 1.22; 95% CI: 1.06-1.41) doubled the odds for treatment failure
- SSTI recurrence occurred in 280 clindamycin patients, 359 TMP-SMX patients and 355 on a beta-lactam
- Recurrence rates were significantly higher among patients prescribed TMP-SMX (HR= 1.26; 95% CI: 1.06-1.49) or beta-lactams (HR=1.42; 95% CI: 1.19-1.69), compared with those prescribed clindamycin
Findings were similar among 41,094 children who did not undergo incision and drainage, the researchers determined, 2,435 of who experienced a treatment failure and 5,436, a recurrence.
As with the other cohort, children prescribed TMP-SMX (HR=1.67; 95% CI: 1.44-1.95) and beta-lactams (HR=1.22; 95% CI: 1.06-1.41) were more likely to experience treatment failure.
Recurrence was also more common with TMP-SMX (HR=1.20; 95% CI: 1.13-1.44) and beta-lactams (HR=1.08; 95% CI: 0.99-1.18) compared with clindamycin in this group.
The researchers concluded that clindamycin is superior to both TMP-SMX and beta-lactams for acute treatment and SSTI recurrence. “This effect was most significant for children with purulent SSTI who underwent drainage,” they wrote.
Furthermore, although beta-lactams are no longer recommended when MRSA is suspected, the researchers suggested that these antibiotics “may still be effective for nonpurulent SSTIs, such as uncomplicated cellulitis or impetigo.”
They emphasized that incision and drainage remain the treatment of choice for purulent SSTIs.
Study limitations include the potential for residual confounding and errors in antibiotic exposure classification and outcomes. Larger, randomized, controlled clinical trials to confirm these findings, the researchers acknowledges, as well as to provide insight into the mechanisms responsible for treatment failure and recurrence.