Trial of MRSA Polymerase Chain Reaction for Pneumonia

Respiratory samples called bronchoalveolar lavage (BAL) gathered from subjects in the PCR arm will be tested for the presence of MRSA using the Cepheid Xpert® Assay. Xpert® is a qualitative in vitro test designed for rapid detection and differentiation of Staphylococcus aureus (SA) and methicillin resistant Staphylococcus aureus (MRSA) using PCR amplification. MRSA is identified by the mecA gene and staphylococcal cassette chromosome mec (SCCmec). Xpert® Assay is approved by the Federal Drug Administration to detect MRSA in soft tissue samples. Once the PCR is completed, the results will be relayed to the treating physician, and antibiotic therapy (vancomycin or linezolid) will be started or stopped based on the study protocol. All BAL samples will be sent for routine bacterial cultures.