Efficacy of a standard methicillin-resistant Staphylococcus aureus decolonisation protocol in routine clinical practice.

Decolonisation may reduce the risk of methicillin-resistant Staphylococcus aureus (MRSA) infection in individual carriers and prevent transmission to other patients. The aims of this prospective cohort study were to determine the long-term efficacy of a standardised decolonisation regimen and to identify factors associated with failure. Patients colonised with MRSA underwent decolonisation, which was considered to be successful if there was no growth in three consecutive sets of site-specific screening swabs obtained weekly post treatment. If patients were successfully decolonised, follow-up cultures were performed 6 and 12 months later. Of 137 patients enrolled, 79 (58%) were successfully decolonised. Of these 79, 53 (67%) and 44 (56%) remained decolonised at 6 and 12 months respectively. Therefore only 44/137 (32%) patients who completed decolonisation were MRSA negative 12 months later. Outcome was not associated with a particular strain of MRSA. Successful decolonisation was less likely in patients colonised with a mupirocin-resistant isolate (adjusted odds ratio: 0.08; 95% confidence interval: 0.02-0.30), in patients with throat colonisation (0.22; 0.07-0.68) and in patients aged >80 years (0.30; 0.10-0.93) compared with those aged 60-80 years. These findings suggest that although initially successful in some cases, the protocol used did not result in long-term clearance of MRSA carriage for most patients.