AT ASM MICROBE 2017
NEW ORLEANS (FRONTLINE MEDICAL NEWS) – Community hospitals could see positive outcomes using a Staphylococcus aureus bacteremia strategy that combines rapid blood cultures to speed diagnosis with antibiotic stewardship to guide treatment.
Many academic medical centers report improved outcomes with this approach. Now a study of 66 patients at a medium-sized hospital in rural North Dakota suggests this strategy translates well to the community hospital setting and can reduce mortality and 30-day readmission rates, and increase cost-effectiveness overall.
“I was pleased to see we were able to replicate the positive outcomes observed in studies from large tertiary care centers with our small cohort,” Marijo Roiko, PhD, microbiology program director for pathology and laboratory services at Altru Health System in Grand Forks, N.D., said in an interview.
Dr. Roiko and colleagues compared 33 patients diagnosed and treated prior to the strategy with 33 others following its implementation. A total of 13 patients, or 39% of each cohort, developed potentially fatal methicillin-resistant S. aureus (MRSA) bacteremia. Patients’ average age ranged from 60 to 64 years, and about two-thirds of each group were men.
The investigators reported that 30-day all-cause mortality decreased from 15.6% to 13.3% after the protocol. In addition, 30-day readmission rates decreased from 25% to 11% of the group diagnosed and managed with the new strategy. Dr. Roiko presented these and other findings from the chart review at the annual meeting of the American Society for Microbiology.
Overall, the average length of stay decreased from 13 days to 10 days among the patients with S. aureus bacteremia. Among the subgroup of patients with MRSA, the length of stay dropped from 15 to 12 days. Among those with methicillin-susceptible S. aureus infections, 11 days decreased to 9 days after institution of the protocol.
The researchers also looked at time to antibiotic deescalation, and the average time decreased from 3 days to 1 day with the new strategy.
“These results demonstrate the utility of rapid testing from positive blood cultures and antibiotic stewardship for patients with Staph. aureus bacteremia,” Dr. Roiko said.
In terms of return on investment, the estimated cost savings associated with the 3-day reduction in length of hospital stay was sufficient to cover the increased capital expenditures and reagent costs, the researchers found. They estimated these increased costs as $78,960, excluding ICU and ancillary charges. The approximate $4,290 saved per day multiplied by 33 patients means the new protocol saved a total of $141,570.
Traditionally, patients with a positive blood culture of S. aureus had a gram stain, followed by provider notification when positive. Targeted antibiotic therapy was either administered at this point or held for culture-based identification and susceptibility testing. In the new protocol, a rapid culture identification panel (FilmArray BCID) is added at the time of gram staining. Positive results are reported to both the provider and pharmacist. Targeted therapy is then either administered or held based on culture-based susceptibility testing (species identification is determined as needed).
The current study findings add to a literature already supporting use of rapid blood cultures and/or stewardship guidance to address S. aureus bacteremia in academic and tertiary care centers ( J Clin Microbiol. 2016;54:2455-63 ; Clin Microbiol Infect. 2015;21:313-22 , and Clin. Infect. Dis. 2015;61:1071-80 .
Dr. Roiko had no relevant financial disclosures.