Utility of qSOFA score in identifying patients at risk for poor outcome in Staphylococcus aureus bacteremia

BACKGROUND: The prognostic capability of the quick Sequential Organ Failure Assessment (qSOFA) bedside scoring tool is uncertain in non-ICU patients with sepsis due to bacteremia given the low number of patients previously evaluated. METHODS: We performed a retrospective cohort study of adult hospitalized patients with Staphylococcus aureus bacteremia (SAB). Medical charts were reviewed to determine qSOFA score, systemic inflammatory response syndrome (SIRS) criteria, and Pitt bacteremia score (PBS) at initial presentation; their predictive values were compared for ICU admission within 48 h, ICU stay duration > 72 h, and 30-day mortality. RESULTS: Four hundred twenty-two patients were included; 22% had qSOFA score ≥2. Overall, mean age was 56y and 75% were male. More patients with qSOFA ≥2 had altered mentation (23% vs 5%, p < 0.0001), were infected with MRSA (42% vs 30%, p = 0.03), had endocarditis or pneumonia (29% vs 15%, p = 0.0028), and bacterial persistence ≥4d (34% vs 20%, p = 0.0039) compared to qSOFA <2 patients. Predictive performance based on AUROC was better (p < 0.0001) with qSOFA than SIRS criteria for all three outcomes, but similar to PBS ≥2. qSOFA≥2 was the strongest predictor for poor outcome by multivariable analysis and showed improved specificity but lower sensitivity than SIRS ≥2. CONCLUSIONS: qSOFA is a simple 3-variable bedside tool for use at the time of sepsis presentation that is more specific than SIRS and simpler to calculate than PBS in identifying septic patients at high risk for poor outcomes later confirmed to have S. aureus bacteremia.