Should we decolonise methicillin-resistant Staphylococcus aureus carriers in the intensive care unit?

Abstract

In many European countries and in the USA, 5–15% of patients are methicillin-resistant Staphylococcus aureus (MRSA) carriers on admission in the intensive care unit (ICU), although significant decline in hospital isolation rates has been observed in some countries in the last decade. MRSA colonisation portends a major risk of subsequent acquired infection. Decolonisation in order to eradicate MRSA carriage has been proposed for a long time for preventing MRSA healthcare-associated infections. Among the variety of drugs used, mupirocin, a topical antibiotic, has been extensively studied and permits nasal decolonisation. The efficacy on MRSA decolonisation is limited by the persistence of carriage at other sites. Systemic antimicrobials have been proposed (rifampin, doxycycline) for the eradication of carriage. Chlorhexidine gluconate 4% body wash has been widely used, especially combined with nasal mupirocin. Usefulness of decolonisation remains controversial. It has been implemented in the guidelines for the prevention of MRSA infections in a few European countries. Other experts only advocate active screening, reinforcement of standard hygiene measures, and isolation precautions in MRSA colonised or infected patients. The disappearance of some endemic clones has contributed to epidemiological changes, irrespective of implemented prevention measures. Lastly, the respective roles of the environmental contamination and of MRSA carriage in healthcare workers have frequently been underestimated. Moreover, the occurrence of resistant strains has been associated with current mupirocin use. There are no universal recommendations but rather institutional protocols that vary according to local epidemiology.