Community-acquired Staphylococcus aureus bacteriology: clinical behavior and severity in children

Introduction: Bacteremia due to Staphylococcus aureus (SA) is one of the most serious infections in the pediatric population. Objectives: To evaluate the epidemiological, clinical and laboratory characteristics of children with bacteremia due to SA acquired in the community (SAAC) and to identify risk factors associated with mortality. Materials and methods: This was a retrospective study in which patients (pts) <= 16 years, hospitalized between 2010-2018, with dx of bacteremia by SAAC were included. Clinical and laboratory data were entered into an Excel database and formatted for analysis. Results: We identified 117 pts with an average age of 56 +/- 53 months, of which 81 were <= 5 years. Bacteremia was associated mainly with pneumonia (47% of the cases), presenting with shock in 38% and admission to the ICU in 40% of the pts. In 27% (32/117) the bacteremia was caused by MRSA. Age <5 years (p = 0.0001), presence of shock (p = 0001), hospitalization in the ICU (p = 0.002, OR 3.58, 95% CI 1.58.3) and mortality (p = 0.03, OR 2.65, 95% CI 1.05-6.7) were associated with MRSA infection. The mortality in this series was 21% (25/117). The presence of comorbidities (p = 0.006, OR3.66, 95% CI 1.4-92), shock (p = 0.0001, OR 87.6, 95% CI 11.5-687.7), multiple infectious foci (p = 0.007, OR3.46, 95% CI 1.3-8.9), MRSA isolation (p = 0.03, OR 2.65, 95% CI 1.1-6.7), and thrombocytopenia <100 000 / mm3 (p = 0.0001, OR 25.3, 95% CI 5-128) were associated with mortality. Conclusions: This study shows the severity of SA bacteremia. Methicillin resistance, comorbidities, the presence of multiple infectious foci and shock were identified as factors associated with mortality.