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Word of the Day

Placebo = antibiotics for skin abscesses in children

Clinical Question:
In children with drained skin abscesses, is no treatment as effective as antibiotic treatment?

Bottom Line:
No treatment produces similar resolution rates as antibiotic treatment in children who have had skin abscesses drained. Antibiotic treatment may prevent new lesions in the short term. (LOE = 1b)

Duong M, Markwell S, Peter J, Barenkamp S. Randomized, controlled trial of antibiotics in the management of community-acquired skin abscesses in the pediatric patient. Ann Emerg Med 2010;55(5):401-407.  [PMID:19409657]

Study Design:
Randomized controlled trial (double-blinded)



Emergency department

Tthe treatment of skin abscesses with antibiotic following incision and drainage (called by some the "Keflex-reflex") has not previously been subjected to controlled study. The authors of this study enrolled 161 children ages 3 months to 18 years with an ultrasound-confirmed skin abscess requiring drainage. Half the children were younger than 5 years. They excluded children with systemic symptoms -- including a temperature greater than 38 degrees C -- and children with chronic disease, with recent antibiotic use, or receiving oral corticosteroid. The majority of infections (80%) were due to community-acquired methicillin-resistant Staphylococcus aureus, with all strains being susceptible to trimethroprim-sulfamethoxazole. Following drainage, the children were randomly assigned, using concealed allocation, to receive a standard does of trimethoprim-sulfamethoxazole or matched placebo twice daily for 10 days. Patients, on average, took only 66% of the total dose, which is similar to rates found in other studies of antibiotic use. Failure, defined as erythema, warmth, induration, fluctuance, tenderness, or drainage after 10 days of treatment, occurred in 4% to 5% of children in both groups, the difference not being significant. However, 8 children were lost to follow-up in the placebo group and 4 children were lost in the treatment group. If we assume a worst case scenario -- that all these children failed treatment -- antibiotic treatment would have been superior. Significantly more children treated with placebo developed new lesions during treatment (25% vs 12.3%; number needed to treat = 8), but new lesion rates were similar at 90 days although the authors lost contact with 35% of thre enrolled patients.


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