Interventions for the skin infection impetigo

Impetigo causes blister-like sores. The sores can fill with pus and form scabs, and scratching can spread the infection. Impetigo is caused by bacteria. It is contagious and usually occurs in children. It is the most common bacterial skin infection presented by children to primary care physicians. Treatment options include topical antibiotics (antibiotic creams), oral antibiotics (antibiotics taken by mouth), and disinfectant solutions. There is no generally agreed standard treatment, and the evidence on what intervention works best is not clear.

We identified 68 randomised controlled trials comparing various treatments for impetigo. Altogether, these studies evaluated 26 oral treatments and 24 topical treatments, including placebo, and results were described for 5708 participants.

Overall, topical antibiotics showed better cure rates than topical placebo.

Two antibiotic creams, mupirocin and fusidic acid, are at least as effective as oral antibiotics where the disease is not extensive. There was no clear evidence that either of these most commonly studied topical antibiotics was more effective than the other.

Topical mupirocin was superior to the oral antibiotic, oral erythromycin.

We found that the oral antibiotic, oral penicillin, is not effective for impetigo, while other oral antibiotics (e.g. erythromycin and cloxacillin) can help.

It is unclear if oral antibiotics are superior to topical antibiotics for people with extensive impetigo.

There is a lack of evidence to suggest that using disinfectant solutions improves impetigo. When 2 studies with 292 participants were pooled, topical antibiotics were significantly better than disinfecting treatments.

Reported side-effects for topical treatments were mild and low in frequency; the treatments sometimes resulted in itching, burning, or staining. Oral antibiotics produced gastrointestinal complaints, such as nausea and diarrhoea, in 2% to 30% of participants, depending upon the specific antibiotic.

Worldwide, bacteria causing impetigo show growing resistance rates for commonly used antibiotics. For a newly developed topical treatment, retapamulin, no resistance has yet been reported.

Authors' conclusions: 

There is good evidence that topical mupirocin and topical fusidic acid are equally, or more, effective than oral treatment. Due to the lack of studies in people with extensive impetigo, it is unclear if oral antibiotics are superior to topical antibiotics in this group. Fusidic acid and mupirocin are of similar efficacy. Penicillin was not as effective as most other antibiotics. There is a lack of evidence to support disinfection measures to manage impetigo.

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Background: 

Impetigo is a common, superficial bacterial skin infection, which is most frequently encountered in children. There is no generally agreed standard therapy, and guidelines for treatment differ widely. Treatment options include many different oral and topical antibiotics as well as disinfectants. This is an updated version of the original review published in 2003.

Objectives: 

To assess the effects of treatments for impetigo, including non-pharmacological interventions and 'waiting for natural resolution'.

Search strategy: 

We updated our searches of the following databases to July 2010: the Cochrane Skin Group Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (from 2005), EMBASE (from 2007), and LILACS (from 1982). We also searched online trials registries for ongoing trials, and we handsearched the reference lists of new studies found in the updated search.

Selection criteria: 

Randomised controlled trials of treatments for non-bullous, bullous, primary, and secondary impetigo.

Data collection and analysis: 

Two independent authors undertook all steps in data collection. We performed quality assessments and data collection in two separate stages.

Main results: 

We included 57 trials in the first version of this review. For this update 1 of those trials was excluded and 12 new trials were added. The total number of included trials was, thus, 68, with 5578 participants, reporting on 50 different treatments, including placebo. Most trials were in primary impetigo or did not specify this.

For many of the items that were assessed for risk of bias, most studies did not provide enough information. Fifteen studies reported blinding of participants and outcome assessors.

Topical antibiotic treatment showed better cure rates than placebo (pooled risk ratio (RR) 2. 24, 95% confidence interval (CI) 1.61 to 3.13) in 6 studies with 575 participants. In 4 studies with 440 participants, there was no clear evidence that either of the most commonly studied topical antibiotics (mupirocin and fusidic acid) was more effective than the other (RR 1.03, 95% CI 0.95 to 1.11).

In 10 studies with 581 participants, topical mupirocin was shown to be slightly superior to oral erythromycin (pooled RR 1.07, 95% CI 1.01 to 1.13). There were no significant differences in cure rates from treatment with topical versus other oral antibiotics. There were, however, differences in the outcome from treatment with different oral antibiotics: penicillin was inferior to erythromycin, in 2 studies with 79 participants (pooled RR 1.29, 95% CI 1.07 to 1.56), and cloxacillin, in 2 studies with 166 participants (pooled RR 1.59, 95% CI 1.21 to 2.08).

There was a lack of evidence for the benefit of using disinfectant solutions. When 2 studies with 292 participants were pooled, topical antibiotics were significantly better than disinfecting treatments (RR 1.15, 95% CI 1.01 to 1.32).

The reported number of side-effects was low, and most of these were mild. Side-effects were more common for oral antibiotic treatment compared to topical treatment. Gastrointestinal effects accounted for most of the difference.

Worldwide, bacteria causing impetigo show growing resistance rates for commonly used antibiotics. For a newly developed topical treatment, retapamulin, no resistance has yet been reported.