Decolonisation

Decolonisation means trying to clear Staphylococcus aureus, including MRSA, that a child carries without symptoms, usually in the nose and sometimes under the fingernails and on the skin. Most children with eczema are colonised with S. aureus (Mooney 2015), and the nose acts as a reservoir that can reseed broken skin. The goal is to stop Infected Eczema or Impetigo from coming back, not to treat an active infection. A typical regimen pairs a nasal antibiotic ointment, Mupirocin or Fusidic Acid, with antiseptic body washes.

Decolonisation [treats] MRSA Mupirocin [part-of] Decolonisation

When guidelines use it. NICE NG190 (infected eczema) and NICE NG153 (impetigo) do not recommend swabbing at the first infection. For infection that keeps coming back, they advise a skin swab and say to “consider taking a nasal swab and starting treatment for decolonisation”. NHS Scotland’s eczema pathway adds that, with recurrent infected eczema, swabbing the noses of the child and family members can show staph carriage and guide the regimen, since carriers in the household can reinfect the child. DermNet describes nasal fusidic acid or mupirocin twice daily for one week each month, often for 6 months, for recurrent staph infection. For MRSA carriers it gives 2–3 times daily for 3–5 days, plus antibacterial washes. DermNet also mentions twice-weekly Bleach Baths as “may be useful”.

NICE NG190 [regulates] Decolonisation Decolonisation [relates] Bleach Baths

Strength of evidence. The evidence is thin. The Cochrane review of anti-staph measures in eczema (George et al. 2019) found insufficient evidence that reducing S. aureus improves eczema. It found no benefit for bleach baths or antiseptic additives. The ICU evidence that mupirocin plus chlorhexidine reduces hospital infections (cited by Antonov 2015) comes from adults in hospital, not toddlers at home. Resistance is a further problem. Antonov et al. (AAC 2015) found mupirocin-resistant S. aureus in 19.3% of children at a New York paediatric dermatology clinic at first culture, so they recommend checking susceptibility before relying on mupirocin. In UK children with eczema, Harkins et al. (BJD 2018) found mupirocin resistance rare but fusidic acid resistance 24% higher than in controls. Decolonisation is therefore rated weak evidence with an unclear direction for eczema outcomes.

Decolonisation [causes] Antimicrobial Resistance Cochrane [contradicts] Decolonisation

For parents of a 1–4-year-old. Decolonisation is a targeted step for a child whose eczema keeps getting infected, chosen with the GP or dermatologist after swabs. It is not a routine part of eczema care. Putting ointment inside a toddler’s nostrils several times a day is hard. Keeping nails short (DermNet also targets carriage under the fingernails) and swabbing and treating household carriers at the same time (NHS Scotland) give it the best chance. The steps that matter most for preventing re-infection are controlling the eczema itself and replacing opened emollient tubs and steroid creams after an infection (NICE CG57). Leftover antibiotic tubes should not be used for flares without signs of infection (Antimicrobial Resistance).

NICE CG57 [relates] Decolonisation

Connections

• Mupirocin — nasal decolonisation agent, source: DermNet
• MRSA — carrier treatment, source: DermNet 2015
• Antimicrobial Resistance — recurrent infections only, after swab, source: NICE NG190
• Staphylococcus aureus — target organism; nasal reservoir, source: DermNet; Mooney 2015
• Fusidic Acid — alternative nasal agent; resistance common in AD isolates, source: DermNet; Harkins 2018
• NICE NG190 — consider nasal swab and decolonisation for frequent recurrence, source: NICE NG190
• NICE NG153 — same advice for recurrent impetigo, source: NICE NG153
• Cochrane — insufficient evidence for anti-staph measures in eczema, source: George 2019
• Bleach Baths — adjunct sometimes paired with decolonisation, source: DermNet 2015
• Infected Eczema — the recurrence decolonisation aims to prevent, source: NICE NG190