Bacteremia and Endovascular Infections: A Retrospective Study of 100 Patients.

BACKGROUND

Lactobacilli are gastrointestinal commensals and may represent skin contamination when isolated in blood cultures. Although uncommon, bloodstream infections and endocarditis have been reported.

METHODS

We conducted a retrospective cohort study of patients with species bacteremia and/or endovascular infections over a 22-year period to identify potential predictors of possible or definite endocarditis using the modified Duke criteria. growth in an initial blood culture set without growth in subsequent blood culture sets collected within 7 days was labeled as blood culture contamination (BCC), and these were excluded from the primary analysis. The primary outcome was the proportion of patients with possible or definite endocarditis. For all isolates, we collected antimicrobial susceptibility data determined via broth microdilution methods according to Clinical and Laboratory Standards Institute guideline M45.

RESULTS

We identified 331 patients with blood and/or endovascular cultures positive for , of whom 100 were included. The primary outcome of possible or definite endocarditis was identified in 29% (29/100) of patients included in the primary analysis. Both the presence of an intracardiac device and/or non-native valve (relative risk [RR], 8.57; 95% CI, 1.89-38.83) and injection drug use (RR, 13.47; 95% CI, 3.18-57.03) were predictors of possible or definite endocarditis. All-cause mortality at ≤90 days was 22% (21/94).

CONCLUSIONS

Nearly 1 in 3 patients with bacteremia had possible or definite endocarditis, though polymicrobial infection was common. Growth of spp. in blood cultures should be considered potentially pathogenic and interpreted in the clinical context before the isolate is labelled as inconsequential.