Background MRSA is a significant problem in ICUs. Data on risks for acquiring MRSA while in PICU are minimal.

Methods Children < 19 years old admitted to PICU between 4/1/2008 & 3/31/2011 had admission & weekly MRSA nasal surveillance done. MRSA affected (colonized or infected) children were compared to unaffected.

Results There were 2861 admissions. Mean age 6.7 yrs (median 4.7); 1444 (50.5%) male. 2632 (92%) of 2861 either had a known history of MRSA or an admission surveillance test and were included in the analysis. 415 (15.8%) were MRSA affected; 264 had known history of MRSA, 132 were MRSA+ on admission and 19 became affected while in PICU (18 colonized & 1 infected). 14 (77.8%) of 18 colonized were identified on weekly surveillance, 4 (22.2%) had a positive non-surveillance culture.19 children who became MRSA affected were further analyzed. There was no significant difference in gender or ethnicity between the two groups. MRSA affected were younger (3.68 vs 6.79 yrs, p=0.03). Mean Hospital length of stay (LOS) prior to PICU admission was longer in the MRSA affected group (2.3 vs 0.6 days, p=0.04). Systemic steroids (p=0.009), mechanical ventilation (p=0.001) and a central venous catheter (CVC) (p=0.001) were all higher in the MRSA affected group; surgery & antibiotic use were not. Mean LOS in the PICU was 4.3 days, Mean LOS in the PICU before becoming MRSA affected was 18 days.

Conclusions Longer hospital stay prior to PICU admission, steroid use, mechanical ventilation and CVC were associated with becoming MRSA affected.