Reduction of periprosthetic Staphylococcus aureus infection by preoperative screening and decolonization of nasal carriers undergoing total knee arthroplasty.

OBJECTIVE: The aim of this study was to evaluate whether the establishment of a preoperative screening and decolonization protocol for Staphylococcus aureus carriers undergoing total knee arthroplasty (TKA) could decrease the incidence of periprosthetic joint infection (PJI) caused by this microorganism. METHODS: We conducted a retrospective study comparing a control group comprising 400 patients (134 men, and 266 women; mean age: 72.2 ± 6.8 years) who went through surgery between January 2009 and December 2013, with a second intervention group of 403 patients (125 men, and 278 women; mean age: 72.4 ± 6.9 years) in which the protocol of screening and decolonization of S. aureus nasal carriers was applied between January 2014 and December 2016. During this latter period patients were preoperatively screened and, if positive, treated with mupirocin nasal ointment and chlorhexidine soap, for 5 days prior to surgery. RESULTS: In the control group, 17 of 400 patients (4.2%) had a SSI, 8 (2%) of them caused by S. aureus and 9 (2.2%) by other microorganisms. In the intervention group 20.6% of patients had a positive S. aureus nasal swab and were treated according to the protocol. 5 of 403 patients (1.2%) in this group had a SSI, 1 (0.2%) due to S. aureus and 4 (1%) to other microorganisms. When comparing surgical-site infection (SSI) rates between the two groups, we found a statistically significant reduction in both global SSI (p = 0.009) and specifically S. aureus SSI (p = 0.02), in the intervention group. No decolonized S. aureus nasal carrier presented a SSI. DISCUSSION: In patients undergoing TKA a preoperative screening and decolonization protocol for S. aureus nasal carriers, using mupirocin nasal ointment and chlorhexidine soap, is an effective measure to reduce the rate of SSI caused by this microorganism. LEVEL OF EVIDENCE: Level III; Therapeutic Study.

Current outcomes and predictors of treatment failure in patients with surgical site infection after elective colorectal surgery. A multicentre prospective cohort study.

OBJECTIVE: To determine current outcomes and predictors of treatment failure among patients with surgical site infection (SSI) after colorectal surgery. METHODS: A multicentre observational prospective cohort study of adults undergoing elective colorectal surgery in 10 Spanish hospitals (2011-2014). Treatment failure was defined as persistence of signs/symptoms of SSI or death at 30 days post-surgery. RESULTS: Of 3701 patients, 669 (18.1%) developed SSI; 336 (9.1%) were organ-space infections. Among patients with organ-space SSI, 81.2% required source control: 60.4% reoperation and 20.8% percutaneous/transrectal drainage. Overall treatment failure rate was 21.7%: 9% in incisional SSIs and 34.2% in organ-space SSIs (p < 0.001). Median length of stay was 15 days (IQR 9-22) for incisional SSIs and 24 days (IQR 17-35) for organ-space SSIs (p < 0.001). One hundred and twenty-seven patients (19%) required readmission and 35 patients died (5.2%). Risk factors for treatment failure among patients with organ-space SSI were age ≥65 years (OR 1.83, 95% CI: 1.07-1.83), laparoscopy (OR 1.7, 95% CI: 1.06-2.77), and reoperation (OR 2.8, 95% CI: 1.7-4.6). CONCLUSIONS: Rates of SSI and treatment failure in organ-space SSI after elective colorectal surgery are notably high. Careful attention should be paid to older patients with previous laparoscopy requiring reoperation for organ-space SSI, so that treatment failure can be identified early.