Individual and institutional predisposing factors of MRSA surgical site infection and outcomes-a retrospective case-control-study in 14 European high-volume surgical centres.

Objectives: To assess incidence rates of surgical site infections (SSI) by MRSA and to determine related factors and clinical outcome compared to MSSA, including country-specific, institutional and patient determinants.

Patients and methods: We performed a subgroup analysis of the Europe-wide SALT (NCT03353532) study population with MRSA SSI from 14 centres in France, Germany, Italy, Spain and the UK.

Results: An overall MRSA SSI incidence of 0.06% (n = 104) was found in 178 903 patients undergoing invasive surgery in 2016. Frequently observed comorbidities were chronic cardiovascular disease, diabetes and solid tumours. Compared to the overall MRSA SSI incidence, incidence rates were significantly higher in Spain (58 of 67 934 cases) and lower in Germany (16 of 46 443 cases; both P < 0.05). Centres with antibiotic stewardship (ABS) and infectious disease (ID) consultation programmes (n = 3/14) had lower MRSA rates (17 of 43 556 cases versus 61 of 83 048 cases, P < 0.05). In bivariate analyses, MRSA SSI patients were significantly older, had higher BMI and more comorbidities compared to MSSA (P < 0.05 each). Surgery performed between 6:00 and 12:00 pm led to higher MRSA proportions among S. aureus SSI (17 of 104 cases versus 62 of 640 cases, P < 0.05).

Conclusions: This study shows low overall and country-specific incidence rates of MRSA SSI in Europe. We could show significant differences between countries as well as between centres with established ABS and ID consultation programmes were observed. The number of those programmes seems too small against this background.