PLoS ONE (Jan 2018)

Risk prediction for Staphylococcus aureus surgical site infection following cardiothoracic surgery; A secondary analysis of the V710-P003 trial.

  • Fleur P Paling,
  • Karina Olsen,
  • Kristin Ohneberg,
  • Martin Wolkewitz,
  • Vance G Fowler,
  • Mark J DiNubile,
  • Hasan S Jafri,
  • Frangiscos Sifakis,
  • Marc J M Bonten,
  • Stephan J Harbarth,
  • Jan A J W Kluytmans

DOI
https://doi.org/10.1371/journal.pone.0193445
Journal volume & issue
Vol. 13, no. 3
p. e0193445

Abstract

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Identifying patients undergoing cardiothoracic surgery at high risk of Staphylococcus aureus surgical site infection (SSI) is a prerequisite for implementing effective preventive interventions. The objective of this study was to develop a risk prediction model for S. aureus SSI or bacteremia after cardiothoracic surgery based on pre-operative variables.Data from the Merck Phase IIb/III S. aureus vaccine (V710-P003) clinical trial were analyzed. In this randomized placebo-controlled trial, the effect of preoperative vaccination against S. aureus was investigated in patients undergoing cardiothoracic surgery. The primary outcome was deep/superficial S. aureus SSI or S. aureus bacteremia through day 90 after surgery. Performance, calibration, and discrimination of the final model were assessed.Overall 164 out of 7,647 included patients (2.1%) developed S. aureus infection (149 SSI, 15 bacteremia, 28 both). Independent risk factors for developing the primary outcome were pre-operative colonization with S. aureus (OR 3.08, 95% confidence interval [CI] 2.23-4.22), diabetes mellitus (OR 1.87, 95% CI 1.34-2.60), BMI (OR 1.02 per kg/m2, 95% CI 0.99-1.05), and CABG (OR 2.67, 95% CI 1.91-3.78). Although vaccination had a significant (albeit modest) protective effect, it was omitted from the model because its addition did not significantly change the coefficients of the final model and V710-vaccine development has been discontinued due to insufficient efficacy. The final prediction model had moderate discriminative accuracy (AUC-value, 0.72).Pre-operative S. aureus colonization status, diabetes mellitus, BMI, and type of surgical procedure moderately predicted the risk of S. aureus SSI and/or bacteremia among patients undergoing cardiothoracic surgery.