Rapid organism identification from blood cultures may decrease mortality and morbidity in BSI through shorter time to appropriate and optimal antibiotic therapy. It may also reduce risk of toxicity in patients with contaminated blood cultures by decreasing time to antibiotic discontinuation. BC-GP allows for rapid diagnosis of BSI or identification of a contaminant but adds laboratory cost for each positive blood culture. The first aim of this study was to compare stewardship outcomes in patients with Gram-positive cocci growing in blood pre- and post-implementation of BC-GP (pre-BC-GP and post-BC-GP). The second aim of the study was to look at the change in cost per patient with a positive blood culture since the addition of BC-GP.
This was a retrospective pre/post study of adult inpatients with positive blood cultures for Gram-positive cocci before (January-February 2014) and after (January-February 2015) implementation of BC-GP. Cost per blood culture was calculated by adding cost of antibiotic regimen and laboratory tests used for each patient.
There were 153 patients in pre-BC-GP group and 162 patients in the post-BC-GP group. Mean time to stopping antibiotics for contaminants was 51 hours in pre-BC-GP group compared to 24 hours in post-BC-GP group (p=0.0006). Compared to pre-BC-GP group, post-BC-GP group had a shorter time to appropriate treatment (1.09 vs 8.03 hours; p=0.01). For patients with methicillin-susceptible Staphylococcus aureus or ampicillin-susceptible Enterococcus faecalis, time to susceptible beta-lactam treatment was shorter in post-BC-GP group (39.4 vs. 76.7 hours; p=0.0007). There was a small, insignificantly increased cost per blood culture of 11.3% (p=0.6534), but the cost per contaminant significantly increased by 73.6% (p=0.0001). There was no difference in length of stay (14 vs 13 days; p=0.61).
BC-GP allowed for a quicker time to adequate treatment, de-escalation, and discontinuation of antibiotics. The use of this test promotes antibiotic stewardship without significantly increasing the overall cost per blood culture. The significant increase in cost per contaminant reinforces the need to decrease the overall contamination rate in order to decrease the cost of new technologies.
K. Bryant, None
M. C. Bowman, None