Children with uncomplicated skin and soft tissue infections can still be treated with cephalexin -- along with drainage and careful wound care -- even though community-acquired methicillin-resistant Staphylococcus aureus (MRSA) has reached epidemic proportions worldwide, a randomized study suggested.
Treatment with cephalexin, a traditional antimicrobial lacking activity against MRSA, resulted in 94% of children improving at 48 to 72 hours, while treatment with clindamycin, which typically is effective in these resistant infections, led to improvements in 97% (P=0.50), according to Aaron E. Chen, MD, of Johns Hopkins, and colleagues.
In addition, complete resolution of the infection was seen at seven days in 97% of children in the cephalexin group and in 94% of those in the clindamycin group (P=0.33), the researchers reported online ahead of print in Pediatrics.
Action Points
- Explain that children with uncomplicated skin and soft tissue infections can still be treated with cephalexin -- along with drainage and careful wound care despite high rates of resistant Staphylococcus aureus (MRSA).
- Note that the study was limited by the small sample size, possible underestimation of recurrence rates, and lack of a placebo arm.
The primary treatment for skin abscesses is incision and drainage, and the role of antibiotics has been uncertain, with several studies finding no difference in outcome with adjuvant drug therapy.
And although most community acquired MRSA infections are limited to the skin and soft tissue, invasive infections including necrotizing pneumonia and septic arthritis have occurred.
"Although there is a limited body of evidence to indicate that antibiotics may not be helpful in the management of purulent [skin and soft tissue infections], especially those that have been treated with [incision and drainage], many clinicians have expressed discomfort with withholding antibiotics for these patients," wrote Chen and colleagues.
To clarify the role of antibiotics for skin and soft tissue infections, the researchers enrolled 200 children ages 6 months to 18 years, randomizing them to receive cephalexin, 40 mg/kg/day, or clindamycin, 20 mg/kg/day.
Wound specimens were obtained, and 69% of the specimens grew MRSA isolates, and 19% grew methicillin-susceptible staphylococci.
More than 90% of the isolates were susceptible to clindamycin, as well as to other antibiotics such as cotrimoxazole. Almost all patients in each group underwent some type of drainage procedure (incision/drainage, expression of pus, or needle aspiration).
Among patients whose cultures grew MRSA, 9% of those receiving cephalexin and 3% of those on clindamycin had worsened at 48 to 72 hours (P=0.15).
Among patients for whom susceptibility data were available, 2% of those treated with clindamycin and 10% of those given cephalexin worsened by 48 to 72 hours (P=0.02).
Lower rates of improvement at 48 to 72 hours were seen in children younger than 1 year (P=0.004).
The only factor associated with a lower rate of resolution by day seven was the presence of fever at baseline (P=0.03).
No serious adverse events were reported. One 13-month-old infant developed mild Clostridium difficile diarrhea that resolved without treatment.
At three months, 18% of children had experienced a recurrence of their infection, but this did not differ according to treatment arm or drug susceptibility.
The investigators noted that since 2004 it has been standard practice at their hospital to treat uncomplicated skin and soft tissue infections with clindamycin, which has significantly increased the use of this drug "despite its numerous disadvantages over traditional antistaphylococcal antibiotics."
These disadvantages include greater cost, concerns about adverse effects, and the development of yet more antibiotic resistance.
The researchers observed that technology capable of rapidly identifying resistant bacteria such as MRSA is being developed, but, at present, clinicians have to choose antibiotics empirically, based on the prevalence of MRSA in the community.
"Until additional studies confirm that adjuvant antibiotics offer no benefit in the management of children with uncomplicated, purulent [skin and soft tissue infections], cephalexin remains a viable empiric antibiotic choice," they stated.
Their study suggested that cephalexin is acceptable for use even in areas where community-acquired MRSA is prevalent, but "in the context of management that already includes careful drainage of purulent collections, attention to wound care, and appropriate follow-up, especially in children of younger age and with fever," they observed.
They explained that some authorities believe that antibiotics lacking in vitro efficacy may provide clinical benefits by other mechanisms such as through immunomodulatory effects.
Limitations of the study included the small sample size, possible underestimation of recurrence rates, and lack of a placebo arm.
Disclosures
The authors declared that they had no financial conflicts.
Primary Source
Pediatrics
Chen A, et al "Randomized controlled trial of cephalexin versus clindamycin for uncomplicated pediatric skin infections" Pediatrics 2011; DOI:10.1542/peds.2010-2053.