Clinical consequences of contaminated blood cultures in adult hospitalized patients at an institution utilizing a rapid blood-culture identification system

Abstract

AbstractObjective:To assess the clinical impact of contaminated blood cultures in hospitalized patients during a period when rapid diagnostic testing using a FilmArray Blood Culture Identification (BCID) panel was in use.Design:Retrospective cohort study.Setting:Single academic medical center.Participants:Patients who had blood culture(s) performed during an admission between June 2014 and December 2016.Methods:Length of hospital stay and days of antibiotic therapy were assessed in relation to blood-culture contamination using generalized linear models with univariable and multivariable analyses.Results:Among 11,474 patients who had blood cultures performed, the adjusted mean length of hospital stay for patients with contaminated blood-culture episodes (N = 464) was 12.3 days (95% confidence interval [CI], 11.4–13.2) compared to 11.5 days (95% CI, 11.0–11.9) for patients (N = 11,010) with negative blood-culture episodes (P = .032). The adjusted mean durations of antibiotic therapy for patients with contaminated and negative blood-culture episodes were 6.0 days (95% CI, 5.3–6.7) and 5.2 days (95% CI, 4.9–5.4), respectively (P = .011).Conclusions:Despite the use of molecular-based, rapid blood-culture identification, contamination of blood cultures continues to result in prolonged hospital stay and unnecessary antibiotic therapy in hospitalized patients.