Performance of the Cepheid Xpert® SA Nasal Complete PCR assay compared to culture for detection of methicillin-sensitive and methicillin-resistant Staphylococcus aureus colonization.

Sensitivity, specificity, positive predictive value, and negative predictive value for the Cepheid Xpert® SA Nasal Complete detection (N = 971) of methicillin-sensitive Staphylococcus aureus was 86.5%, 98.5%, 94.6%, and 96.1%; detection of methicillin-resistant S. aureus was 89.3%, 97.9%, 79.8%, and 99.0%, respectively. Our results show that testing on long-term care facility patients had lower sensitivity and specificity compared to acute care patient results.