Health Economics of Bacterial Fluorescence Imaging: Cost Savings from Earlier Identification of Patients with Moderate-to-Heavy Bacterial Loads

Introduction: Point-of-care bacterial fluorescence imaging (FL-imaging) provides real-time information about the presence and location of bacteria, leading to earlier identification of wounds with moderate-to-heavy bacterial loads in a recent clinical trial[1]. A model was developed to understand the relationship between earlier identification and cost expenditures. 

Assumptions: This model assumed that: (1) progression through the bacterial load continuum is dependant on bacterial load at a wound’s initial presentation[2,3] and (2) >10^4 CFU/g is a tipping point of bacterial load at which wound treatment plan must switch from one of vigilance to one of intervention2.

Modeling: Each clinical trial patient’s (n=191) cost level placement on the bacterial load continuum[2,3] was compared between standard of care assessment for clinical signs and symptoms of infection (CSS) and CSS + FL-imaging.  True bacterial load was determined from biopsies and qPCR. The predicted progression of each patient within the pyramid was based on Medicare chronic wound progression and expenditure data from 2252 chronic wound patients[3].  

Results: FL-imaging correctly identified more patients with bacterial loads >10^4 CFU/g. Earlier identification of bacterial presence was predicted to decrease the percent of wounds escalating to local, spreading, and systemic infection, resulting in average long-term cost savings of $9273 USD per patient. 

Conclusions: Earlier identification of concerning bacterial loads would lead to earlier interventions. These interventions (e.g. targeted debridement, additional cleaning, antimicrobial selection)2 prevented long-term expenditures associated with spreading and systemic infections (e.g. hospitalization[3]) and amputations.