Is Panton-Valentine leucocidin (PVL) toxin associated with poor clinical outcomes in patients with community-acquired Staphylococcus aureus bacteraemia?

Introduction. Panton-Valentine leucocidin (PVL) toxin is a potential determinant of virulence associated with S. aureus infection. Gap Statement. The contribution of PVL to S. aureus pathogenicity remains unclear. Aim. To compare clinical outcomes in hospitalized patients with PVL-positive and PVL-negative community-acquired (CA) S. aureus bacteraemia. Methods. Three national datasets were combined to provide clinical and mortality data for patients with CA S. aureus blood culture isolates sent to the UK reference laboratory for PVL testing, August 2018 to August 2021. Multivariable logistic regression models were built for the effect of PVL positivity on 30 day all-cause mortality and 90 day readmission. Results. In 2191 cases of CA S. aureus bacteraemia, there was no association between PVL and mortality (adjusted odds ratio, aOR: 0·90, 95 % confidence interval, CI: 0·50-1·35, P=0·602) and no difference in median LOS (14 versus 15 days, P=0.169). PVL-positive cases had lower odds of readmission (aOR 0·74, CI 0·55-0.98, P=0·038). There was no evidence that MRSA status modified this effect (P=0·207). Conclusions. In patients with CA S. aureus bacteraemia PVL toxin detection was not associated with worse outcomes.