S.Areus is the most common bacteria associated with surgical site infection and 20-30% of people are carriers of nasal MSSA, up to 5% carry MRSA. . Wertheim et al. screened 14,000 patients for nasal s.aureus and monitored for s.aureus bacteremia, and found a 3x higher risk in the nasal carriers , suggesting that nasal bacteria could theoretically lead to seeding of a prosthetic implant. In a study of all orthopedic patients, the infection rate among MRSA nasal carriers was significantly higher than noncarriers (0.97% vs. 0.14%) .
Technique to evaluate for S.Aureus Colonization.
Nasal swab for diagnosis 1- 3 months before surgery. If positive, then patients perform chlorhexadine showers, and 2% mupirocin nasal oitments daily until a week before surgery. All MRSA positive patients receive vancomycin instead of ancef before incision.
Implementation of this program has decreased the prevalence of MRSA at an orthopedic specialty hospital by 33% when strict adherence (95%) was maintained . S. Aureus eradication was associated with a significant decrease in infection rates  . A meta-analysis similarly demonstrated at many hospitals, an eradication program decreased surgical site infections, wound complications, and reduced hospital costs. However, a follow up meta-analysis that only examined randomized prospective trials found a trend but not statistical significance to support the use of these screening and decolonizing protocols [7, 8].
1. Hadley, S., et al., Staphylococcus aureus Decolonization Protocol Decreases Surgical Site Infections for Total Joint Replacement. Arthritis, 2010. 2010: p. 924518.
2. Wertheim, H.F., et al., Risk and outcome of nosocomial Staphylococcus aureus bacteraemia in nasal carriers versus non-carriers. Lancet, 2004. 364(9435): p. 703-5.
3. Kim, D.H., et al., Institutional prescreening for detection and eradication of methicillin-resistant Staphylococcus aureus in patients undergoing elective orthopaedic surgery. J Bone Joint Surg Am, 2010. 92(9): p. 1820-6.
4. Mehta, S., et al., Impact of preoperative MRSA screening and decolonization on hospital-acquired MRSA burden. Clin Orthop Relat Res, 2013. 471(7): p. 2367-71.
5. Courville, X.F., et al., Cost-effectiveness of preoperative nasal mupirocin treatment in preventing surgical site infection in patients undergoing total hip and knee arthroplasty: a cost-effectiveness analysis. Infect Control Hosp Epidemiol, 2012. 33(2): p. 152-9.
6. Deirmengian, G.K., et al., Aspirin Can Be Used as Prophylaxis for Prevention of Venous Thromboembolism After Revision Hip and Knee Arthroplasty. J Arthroplasty, 2016.
7. Verhoeven, P.O., et al., Letter to the editor: Staphylococcus aureus screening and decolonization in orthopaedic surgery and reduction of surgical site infections. Clin Orthop Relat Res, 2013. 471(11): p. 3709-11.
8. Bode, L.G., et al., Preventing surgical-site infections in nasal carriers of Staphylococcus aureus. N Engl J Med, 2010. 362(1): p. 9-17.