2026 Southeastern Residency Conference

Outcomes Associated with Early Versus Late Infectious Disease Consult for Staphylococcus aureus Bacteremia

Authors: Peyton Johnson, Alanna H. Rufe, Adam Harnden, Nancy Bailey, Sarah Vines, W. Creed Carleton

Purpose: Staphylococcus aureus is the most common Gram-positive cause of bacteremia and is a serious infection with up to 30% mortality. Optimal management of Staphylococcus aureus bacteremia (SAB) includes timely source identification, repeat blood cultures, echocardiography, and appropriate antimicrobial therapy. Infectious disease (ID) consultation is recommended as it is associated with improved patient outcomes, with some literature correlating earlier consultation with even better outcomes. At Jackson Hospital and Clinic most patients with SAB receive an ID consult, but the timing is variable. This study evaluated how timing of ID consultation impacts outcomes for patients with SAB.

Methods: This was an institutional review board approved, retrospective chart review at a 344-bed community hospital in Montgomery, Alabama. Adult patients were included if they had a diagnosis of SAB and received an ID consultation between October 1, 2023, and March 31, 2025. Patients were identified via a clinical decision support tool that reported blood cultures growing Staphylococcus aureus. Key exclusions included polymicrobial bacteremia, expiration within 72 hours of index blood culture, or refusal of treatment. Patients were stratified into two cohorts: early consult (ID consultation < 4 days from SAB diagnosis) and late consult (> 4 days).
The components of the primary composite endpoint were source identification, follow-up blood cultures, echocardiography within 5 days, administration of optimal parenteral antistaphylococcal therapy, and adherence to recommended treatment durations. Secondary endpoints included length of stay, in-hospital mortality, 30-day readmission, acute kidney injury, duration of inpatient antimicrobial therapy, and source-control procedures. Baseline demographics, comorbidities, and methicillin-resistant Staphylococcus aureus incidence were extracted. A priori power analysis estimated 88 patients to achieve 80% power. Additional statistical tests were used as appropriate.

Results: A total of 153 patient encounters were reviewed, and 93 patients met inclusion criteria. Among the included patients, 63 patients received an early infectious disease consultation, while 30 patients received a late consultation. Patients were excluded in the absence of ID consultation, polymicrobial bacteremia, death within 72 hours of admission, discharge against medical advice, and duplicate encounters. Baseline characteristics were similar between the early and late consultation groups, including age (60.3 vs 63.1 years), percentage of male patients (65% vs 63.3%), and incidence of methicillin-resistant Staphylococcus aureus (55.6% vs 56.7%).
Mean time to ID consultation was 1.9 days in the early group compared with 4.8 days in the late group (p < 0.0001). The primary composite quality-of care endpoint was achieved in 62% (n = 39/63) of the patients in the early consultation group compared with 53% (n = 16/30) in the late consultation group (p = 0.58). Acute kidney injury occurred significantly less frequently among patients who received early consultation (9.5% vs 33.3%, p = 0.01). No significant difference was found in length of stay, in-hospital mortality, 30-day readmission, duration of antimicrobial therapy, or source-control procedures between groups.

Conclusion: In this retrospective study of 93 patients with Staphylococcus aureus bacteremia, early ID consultation was not associated with a statistically significant improvement in the composite quality-of-care endpoint compared with later consultation. This may be due to an overestimation of the effect size. Early ID involvement was associated with a significantly lower incidence of acute kidney injury, which may support quality initiatives to standardize ID involvement. Implementing an automatic ID consult at the time initial blood cultures identify Staphylococcus aureus may reduce variability in quality-of-care and should be evaluated in future research.