Universal decolonization with mupirocin is effective in decreasement of overall hospital-acquired methicillin-resistant S. aureus infection rates

Background: The aim of this quasi-experimental before and after study aimed to evaluate the effect of universal mupirocin decolonization on the incidence of microbiologically-confirmed S. aureusnosocomial infections in three intensive care units (ICU) of a tertiary-care educational hospital from a developing country.

Methods: This study was performed at three ICUs (Anaesthesiology&Reanimation-Respiratory Diseases and Neurology) of a tertiary care general teaching hospital with a total of active 55 beds. After 1 September 2014, patients admitting to the three mentioned ICUs, received  nasal mupirocin ointment (Two times a day, for five days). The preintervention period was considered as January-August 2014 and post intervention period was considered as September 2014-March 2015. The nosocomial infection surveillance was performed via active prospective surveillance by using CDC criteria. Bacteriological culture and identification of S. aureus from any clinical sample was performed with conventional methods. Antibacterial susceptibility testing was performed with disc-diffusion test according to CLSI criteria.

Results: Results of the study periods are shown in table 1.  Incidence density of any kind of  methicillin-resistant S aureus (p:0.03) but not overall S. aureus nosocomial infection rate (p:0.4) decreased significantly. MRSA rate in any infection type decreased to 27% from 60%. The decrease was most prominent in pneumonia.

Conclusion: Overall MRSA infection incidence and MRSA rate decreased significantly via universal decolonization. Interestingly the decrease was more prominent in pneumonia. Our findings suggest that this strategy may be beneficial in resource-limited countries. 

Table: S. aureus nosocomial infection incidence per 1000 patient days.

	2014 January-August	2014 September-2015 March
Overall SA	3,4 (35/10299)	2,6 (22/8347)
Overall MRSA	2 (21/10299)	0,7 (6/8347)
Pneumonia SA	1,9 (20/10299)	0,7 (6/8347)
Pneumonia MRSA	1,1 (11/10299)	0 (0/8347)
Bacteremia SA	1,2 (12/10299)	1,7 (14/8347)
Bacteremia MRSA	0,8 (8/10299)	0,7 (6/8347)
Other SA	0,3 (3/10299)	0,2 (2/8347)
Other MRSA	0,2 (2/10299)	0 (0/8347)