Nasal colonization of Staphylococcus aureus and the risk of surgical site infection after spine surgery: a meta-analysis

Abstract

BACKGROUND CONTEXTNasal colonization of Staphylococcus aureus may increase the risk of surgical site infection (SSI) after spine surgeries, although the results of previous studies were inconsistent. PURPOSETo evaluate the influences of nasal colonization of S. aureus, methicillin-susceptible SA, and methicillin-resistant SA (MRSA) on the incidence of SSI after spine surgery. STUDY DESIGN/SETTINGSystematic review and meta-analysis. PATIENT SAMPLESeven studies including 10,650 patients who underwent nasal swab examination before spine surgeries were included, and 221 patients had nasal colonization of MRSA at baseline. OUTCOME MEASURESAssociation between baseline nasal colonization of S. aureus, MRSA, and SSI after spine surgery. METHODSRelevant follow-up studies were identified through systematic searches of the PubMed, Embase, and Cochrane Library databases. A random effects model was applied to pool the results. Subgroup analyses were performed according to whether MRSA decolonization was applied. RESULTSDuring follow-up, a total of 244 SSI events occurred, including 57 MRSA-SSI events. Pooled results showed that nasal S. aureus (risk ratio [RR]=0.75, p=.22) or methicillin-susceptible SA colonization (RR=0.60, p=.22) did not significantly affect the risk of overall SSI after surgeries. However, nasal MRSA colonization was associated with significantly increased risks of overall SSI and MRSA-SSI (RR=2.52 and 6.21, respectively, both p<.001). Interestingly, the associations between nasal MRSA colonization and increased risks of overall and MRSA-SSI remained significant in studies without MRSA decolonization, but became insignificant in studies with MRSA decolonization. CONCLUSIONSNasal MRSA colonization may be associated with increased risks of overall SSI and MRSA-SSI after spine surgeries, and nasal MRSA decolonization may be associated with a reduction of SSI in these patients.