C5. Bacteremia and endocarditis
Oral Abstract Submission
P. Brandon Bookstaver, PharmD, FCCP, FIDSA, BCPS, AAHIVP
University of South Carolina
Disclosure: ALK Abello Inc.: Grant/Research Support, Advisor or Review Panel member
FreeCE.com: Other Financial or Material Support, Content developer & speaker
Melinta Therapeutics: Advisor or Review Panel member
A quick version of the Pitt Bacteremia Score (qPitt) was recently derived based on five binary variables each assigned one point (Table 1). The qPitt broadened respiratory failure definition, simplified mental status, and eliminated fever from the original Pitt bacteremia score. The qPitt had high discrimination in predicting mortality in patients with Gram-negative bloodstream infection (BSI) and outperformed other acute severity of illness scores. This retrospective cohort study aims to evaluate the qPitt performance in patients with Staphylococcus aureus BSI and compare its discrimination to quick Sepsis Related Organ Failure Assessment (qSOFA).
Hospitalized adult patients with S. aureus BSI at Prisma Health-Midlands hospitals in South Carolina from January 1, 2015 to December 31, 2017 were identified. Multivariate logistic regression was used to examine risk factors for 28-day all-cause mortality. Area under receiver operating characteristic curve (AUROC) was used to evaluate discrimination of qPitt and qSOFA in predicting 28-day mortality (primary outcome). In-hospital and 90-day mortality were examined as secondary outcomes.
Among the 398 patients with S. aureus BSI, median age was 63 years, 241 (61%) were men, 173 (43%) had methicillin-resistant S. aureus (MRSA) BSI, and 95 (24%) died within 28 days of BSI. After adjustments for age, clinical and microbiological characteristics in the multivariate model, all five individual components of qPitt were independently associated with 28-day mortality (Table 1). There was a 3-fold increase in 28-day mortality for each point increase in qPitt (odds ratio 3.11, 95% confidence intervals: 2.40-4.02, p<0.001). Mortality was 2% in patients with qPitt of 0 and increased to 14%, 24%, 50%, and 82% in patients with qPitt of 1, 2, 3, and ≥4, respectively. The qPitt had higher discrimination in predicting 28-day mortality than qSOFA (AUROC 0.82 vs. 0.77, p=0.001). The qPitt also performed well in predicting in-hospital and 90-day mortality (AUROC 0.80 and 0.76, respectively).
The qPitt has good discrimination in predicting mortality in patients with S. aureus BSI. These results support using the qPitt as an acute severity of illness score in future studies.