Interventions to Reduce Staphylococcus aureus in the Management of Atopic Eczema: An Updated Cochrane Review

Abstract and Introduction

Abstract

Background An association between the bacterium Staphylococcus aureus and atopic eczema has been recognized for many years. Although few would dispute the benefit of systemic antibiotics in people with overtly clinically infected eczema, the clinical role of S. aureus in causing inflammatory flares in clinically uninfected eczema is less clear.
Objectives/Methods To see if atopic eczema can be improved by antistaphylococcal agents, we performed a systematic review of randomized controlled trials (RCTs) using Cochrane Skin Group's Specialised Register, the Cochrane Central Register of Controlled Trials, MEDLINE (from 2000), EMBASE (from 1980), the metaRegister of Current Controlled Trials (to March 2009), plus manual searching of references and conference proceedings. RCTs that compared interventions to reduce S. aureus in people with atopic eczema with no treatment, vehicle, or another active compound were included. Publication status and language were not barriers to inclusion.
Results Twenty-six studies involving 1229 participants were included. The studies were generally short term and of poor quality. There was no significant difference in global outcome for clinically infected eczema when oral antibiotics were compared with placebo [one study, relative risk (RR) 0·40, 95% confidence interval (CI) 0·13–1·24] or when topical steroid antibiotic combinations were compared with steroid alone (two studies, RR 0·52, 95% CI 0·23–1·16). One study of children with infected eczema that added bleach to bathwater showed a significant improvement in eczema severity when compared with bathwater alone, although the difference could have been explained by regression to the mean. Although antistaphylococcal interventions reduced S. aureus numbers in people with clinically uninfected eczema, none of the studies showed any clinical benefit.
Conclusions We failed to find any evidence that commonly used antistaphylococcal interventions are clinically helpful in people with eczema that is not clinically infected. Their continued use should be questioned in such situations, until better and longer-term studies show clear evidence of clinical benefit.

Introduction

Atopic eczema now affects around 15% of children worldwide, and appears to be on the increase especially in younger children for reasons which are largely unknown.^[1] An association between the bacterium Staphylococcus aureus and atopic eczema has been recognized for many years. It has been demonstrated that S. aureus can be isolated from 90% of atopic eczema skin lesions,^[2] and the density of S. aureus tends to increase with the clinical severity.^[3] Although few would dispute the benefit of systemic antibiotics in people with overtly clinically infected eczema,^[4] the clinical role of S. aureus in causing inflammatory flares in clinically uninfected eczema is less clear. Some studies have shown that S. aureus may promote inflammation through superantigen activation.^[5] The evidence for use of antistaphylococcal agents is mainly theoretical. Yet the last 20 years has witnessed a boom in topical and oral preparations that have been formulated with antimicrobial products to reduce S. aureus in people with eczema – either as single agents or in combination with other products such as topical corticosteroids. Such preparations may be associated with adverse events such as contact and irritant dermatitis, and promotion of wider drug resistance in the community. Despite these concerns, antistaphylococcal products such as bath additives and topical antibiotic/corticosteroid combinations are very widely used, especially in the community setting. We previously undertook a systematic review of all randomized controlled trials (RCTs) of interventions to reduce S. aureus in eczema to find out whether they work better than standard therapy in clinically infected or clinically uninfected eczema.^[1] Here we present the results of the updated review.

The British Journal of Dermatology. 2010;163(1):12-26. © 2010  Blackwell Publishing

Cite this: Interventions to Reduce Staphylococcus aureus in the Management of Atopic Eczema: An Updated Cochrane Review - Medscape - Mar 01, 2010.