Emergence of staphylococcal cassette chromosome mec type IV methicillin-resistant Staphylococcus aureus as a cause of ventilator-associated pneumonia.

Staphylococcal cassette chromosome mec (SCCmec) type IV methicillin-resistant Staphylococcus aureus (MRSA) strains were identified in 8 (19.5%) of 41 consecutive patients with MRSA ventilator-associated pneumonia (VAP) in this retrospective, observational study. There were no significant differences in VAP severity and crude mortality rates between patients with SCCmec type II strains and patients with SCCmec type IV strains.