Positive nasal culture of methicillin-resistantStaphylococcus aureus(MRSA) is a risk factor for surgical site infection in orthopedics

BACKGROUND: Although nasal carriage of MRSA has been identified as one of the risk factors for surgical site infection (SSI) with MRSA, there have been no reports of this in the orthopedics field. METHODS: This prospective observational cohort study included 2,423 consecutive patients who were admitted to our department over 26 months and who underwent orthopedic surgery. We examined the relationship between pre-existing nasal MRSA and subsequent occurrence of SSI with MRSA. RESULTS: 63 patients (2.6%) had a positive nasal MRSA culture. 15 patients (0.6%) developed SSI with MRSA. The occurrence of SSI with MRSA in nasal MRSA carriers was significantly higher than that in non-carriers (4 out of 63 (6.3%) vs. 11 out of 2,360 (0.5%); p < 0.001) (adjusted OR: 11; 95% CI: 3-37; p = 0.001). INTERPRETATION: We recommend appropriate treatment of patients who are nasal carriers of MRSA before orthopedic surgery.