Staphylococcus aureus Bacteremia in the Pediatric Emergency Department and Predictors of Poor Outcome.

Background: Staphylococcus aureus has become the leading cause of bacteremia among previously healthy children older than 5 years.

Methods: We aimed to describe the infants presenting to pediatric emergency departments and diagnosed with S. aureus bacteremia (SAB) and identify predictors (clinical and laboratory variables) of poor outcome (complications, sequelae or death). We performed an observational study and subanalysis of a multicenter prospective registry, including every patient under the age of 18 years with a positive blood culture obtained at any of the 22 participating Spanish pediatric emergency departments between 2011 and 2016. We considered chronic diseases, immunosuppressive treatment and the presence of mechanical devices as risk factors for SAB.

Results: Of the 229 patients with SAB, 176 (76.9%) were previously healthy, 192 (83.8%) had a normal pediatric assessment triangle and 158 (69.0%) had an associated focal infection (mainly osteoarticular infection, skin and soft tissue infection and pneumonia). Fifty-three patients (23.1%) had 1 or more risk factors for SAB. Thirty-one (13.5%) presented a poor outcome, including 4 deaths (1.7%). A poor outcome was more common in patients with SAB risk factors [odds ratio (OR): 7.0; 95% CI: 3.2-15.4], abnormal PAT (OR: 5.9; 95% CI: 2.6-13.3), elevated procalcitonin (OR: 1.2; 95% CI: 1.05-1.3) and C-reactive protein, the latter being the only independent predictor of poor outcome (OR: 1.01; 95% CI: 1.01-1.02).

Conclusions: Overall, children with SAB are previously healthy, appear well, and have an associated focal infection. One of 7 had a poor outcome, with C-reactive protein being the only predictor identified.