[O415]
Magnitude of bacteraemia predicts one-year mortality
K. Gradel, H. Schønheyder, M. Søgaard, C. Dethlefsen, H. Nielsen. (
Objectives: All hospitals in our region use the BacT/Alert®
blood culture (BC) system with a 3-bottle BC set for adults. We hypothesised
that the magnitude of bacteraemia (i.e., number of positive bottles in the
initial BC set) predicts one-year mortality. Methods: In a
population-based study we analysed all patients with monomicrobial
bacteraemia in North Jutland County, Denmark, 1996–2004. Data from the County
Bacteraemia Registry were linked to the Hospital Discharge Registry
(comorbidity) and the Danish Civil Registration System (vital status, including
date of emigration or death). Patients with a BC index of 1 (i.e., one positive
bottle) were chosen as the reference group. We computed Kaplan–Meier curves and
performed Cox regression analyses to estimate mortality rate ratios (MRRs) with 95% confidence intervals [CIs]
30 and 365 days after the initial BC sampling date, first in crude analyses,
second in analyses adjusted for age, comorbidity, acquisition of infection
(community, nosocomial, or healthcare-related), and
incident or recurrent episode. In addition we stratified the analyses on
acquisition of infection and pathogen group. Results: A total of 6,955
patients had 8,152 episodes of monomicrobial
bacteraemia, among which one-year follow-up was possible for 8,108 (99.5%). Of
these, 2,539, 1,511 and 4,058 episodes had a BC index of 1, 2 and 3,
respectively. In crude analyses, 30-day MRRs were
0.98 [0.851.14] and 1.20 [1.071.34] for BC indices 2 and 3, respectively, and
similar MRRs were found after 1 year (0.99 [0.891.09]
and 1.12 [1.041.21]). All estimates remained unchanged in the adjusted
analyses. Results for community-acquired and healthcare-related bacteraemia
episodes were consistent with the non-stratified results, whereas all MRRs for nosocomial infections
were close to 1. A BC index of 3 had the strongest long-term prognostic impact
in pneumococcal bacteraemia (n = 855) (adjusted MRR
1.60 [1.092.34]).Conclusions: In patients with community-acquired or
healthcare-related bacteraemia, high magnitude of bacteraemia (i.e., a BC index
of 3) predicted increased 30-day as well as 365-day mortality.
Session Info: Community-acquired bacterial infection II
Session Type: Oral presentations