akinohanayuki ブログ

学位を持っても、センスのない、感染制御専門薬剤師のブログ.  I have Ph.D. but less sense ID pharmacist.





Impetigo is a contagious superficial bacterial infection manifesting on the face and extremities with lesions that progress from papules to vesicles, pustules, and crusts. Less common manifestations include bullous impetigo and ecthyma. Impetigo may be followed by poststreptococcal glomerulonephritis or rheumatic fever.
The principal pathogen is S. aureus. In contrast to skin abscess, community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) is an uncommon cause of impetigo. Beta-hemolytic streptococci (primarily group A, but occasionally other serogroups such as C and G) cause a minority of cases, either alone or in combination with S. aureus.
For management of impetigo with a small number of lesions, we recommend treatment with topical therapy rather than oral therapy (Grade 1A). Topical mupirocin and topical retapamulin are options for topical therapy. Mupirocin is applied three times daily and retapamulin is applied twice daily. The recommended duration of treatment for these medications is five days
For patients with numerous impetigo lesions, we recommend treatment with oral antibiotic therapy (Grade 1B). The antibiotic selected should be effective for the treatment of both S. aureus and streptococcal infections; dicloxacillin and cephalexin are appropriate treatments. Oral antibiotic therapy should be given for seven days. In the setting of suspected CA-MRSA, appropriate choices include doxycycline, clindamycin, or trimethoprim-sulfamethoxazole
Handwashing is important for reducing spread among children, and other preventive measures employed in reducing the spread of staphylococci may also be helpful. 
Interventions for impetigo.
Cochrane Database Syst Rev. 2012;1:CD003261.
  • 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 METHODS: 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, andsecondary 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 studieswith 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.
  • 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.
  • PMID 22258953
A systematic review and meta-analysis of treatments for impetigo.
Br J Gen Pract. 2003;53(491):480.
  • BACKGROUND: Impetigo is a common clinical problem seen in general practice. Uncertainty exists as to the most effective treatment, or indeed if treatment is necessary.
  • AIM: To determine the most effective treatment for impetigo in a systemically well patient.
  • DESIGN OF STUDY: Systematic review and meta-analysis.
  • METHOD: Databases were searched for relevant studies. The Cochrane highly sensitive randomised controlled trial (RCT) search string was employed and combined with the word 'impetigo' as the MeSH term and keyword. The bibliographies of relevant articles were searched for additional references. RCTs that were either double- or observer-blind, and involved systemically well patients of any age in either primary or secondary care settings, were included. Studies that selected patients on the basis of skin swab results were excluded, as were studies that were not in English. Cure or improvement of impetigo reported at seven to 14 days from start of treatment was the primary outcome measure.Meta-analysis was performed on homogeneous studies.
  • RESULTS: Three hundred and fifty-nine studies were identified, of which 16 met the inclusion criteria. Meta-analysis demonstrated that topical antibiotics are more effective than placebo (odds ratio [OR]= 2.69, 95% confidence interval [CI]= 1.49 to 4.86). There is weak evidence for the superiority of topical antibiotics over some oral antibiotics, such as erythromycin (OR = 0.48, 95% CI = 0.23 to 1.00). There is no significant difference between the effects of mupirocin and fusidic acid (OR = 1.76, 95% CI = 0.77 to 4.03).
  • CONCLUSION: This review found limited high-quality evidence to inform the treatment of impetigo. From that which is available, we would recommend the use of a topical antibiotic for a period of seven days in a systemically well patient with limited disease. Further research is needed on the role of flucloxacillin and non-antibiotic treatments for impetigo.
  • PMID 12939895