BACT-URIE: A novel score integrating Bacteriuria to predict infective endocarditis in patients with Staphylococcus aureus Bacteremia

Abstract Background Infective endocarditis (IE) is a serious complication of Staphylococcus aureus bacteremia (SAB). Systematic echocardiographic evaluation, especially when including TEE, is resource-intensive. Existing risk scores do not include S. aureus bacteriuria, a potential marker of hematogenous spread. We assessed whether bacteriuria improves IE risk stratification. Methods We retrospectively analyzed two temporally distinct cohorts of adult SAB patients in a French tertiary hospital: a derivation cohort (2012–2019, n=233) and a validation cohort (2020–2023, n=156). Patients with proven urinary tract infection were excluded. Logistic regression identified predictors of IE, which were converted into weighted points to develop two scores: Day 1 (baseline variables) and Day 4 (including persistent bacteremia ≥72 h). Performance was compared with VIRSTA and PREDICT. Results IE occurred in 14.6% of the derivation cohort and 14.7% of the validation cohort. Independent predictors were intracardiac devices, community acquisition, bacteriuria, septic emboli, and persistent bacteremia. AUROCs for the Day 1 and Day 4 scores were 0.78 and 0.81 in derivation, and 0.91 and 0.93 in validation. At thresholds of 2 and 3, sensitivities were 67.65% and 70.59%, with NPVs of 93.29% and 93.83%, respectively. Compared with VIRSTA and PREDICT, BACT-URIE showed higher sensitivity in this cohort. Conclusion BACT-URIE is an exploratory score incorporating S. aureus bacteriuria to predict IE in SAB. Prospective multicenter validation is required before clinical implementation.