Outcomes of rapid identification for gram-positive bacteremia in combination with antibiotic stewardship at a...

Rapid diagnostics for bloodstream infections have been shown to improve outcomes. Most studies have focused on rapid diagnostics for a single pathogen and have been conducted in academic medical centers. The Verigene Gram-Positive Blood Culture Test (BC-GP) identifies 12 gram-positive organisms and 3 genetic markers of antibiotic resistance from positive blood culture media in 2.5 hours. This study evaluates implementation of the Verigene BC-GP panel in combination with real-time support from the Antibiotic Stewardship Team (AST) in a community hospital system.

This multicenter, pre-post, quasi-experimental study was conducted at the five hospitals that compose Scripps Healthcare. Rapid diagnostic testing was performed at a central laboratory from 7 a.m.-7 p.m. Pharmacists notified physicians of results and assisted with antibiotic modifications. The primary outcomes were average time to targeted antibiotic therapy and difference in antibiotic duration for contaminants. Secondary end points included hospital length of stay, mortality, pharmacy costs, and overall hospitalization costs. Adult patients with a gram-positive bacteremia admitted in 2011 (pre-rapid testing) were compared with those admitted in 2014 (post-rapid testing).

There were 103 patients in the preintervention group and 64 patients in the intervention group. The optimized identification process, combined with AST intervention, improved mean time to targeted antibiotic therapy (61.1 vs 35.4 hrs, p<0.001) and decreased mean duration of antibiotic therapy for blood culture contaminants (42.3 vs 24.5 hrs, p=0.03). Median length of stay (9.1 vs 7.2 days, p=0.04) and overall median hospitalization costs ($17,530 vs $10,290, p=0.04) were lower in the intervention group. Mortality was similar between groups (9.1% vs 9.2%, p=0.98).

Rapid identification of gram-positive blood cultures with AST intervention decreased time to targeted antibiotic therapy, length of unnecessary antibiotic therapy for blood culture contaminants, length of stay, and overall hospital costs.