Real-Life Experience and Diagnostic Utility of the BioFire Joint Infection PCR Panel in Bone and Joint Infections: Analysis of a Prospective Validation Study

Abstract

Microbiological diagnosis is central for adequate treatment of bone and joint infections. Culture-based methods have a limited diagnostic sensitivity and a long turnaround time (TAT). The objective of this study was to compare the diagnostic performance of BioFire Joint Infection Panel Investigational Use Only version (hereafter BioFire)-a sample-to-result multiplex PCR panel-with culture-based methods and 16S ribosomal RNA (rRNA) PCR and sequencing, when available. This study presents a retrospective analysis of a prospective validation study of the BioFire panel. Specimens were obtained from consecutive patients evaluated for suspected bone and joint infections and processed using culture, BioFire, and 16S rRNA PCR and sequencing. Final clinical diagnosis was used as the reference for definition of infection. Samples, including synovial fluid, bone and periarticular tissue, were obtained from 57 patients, 39 of whom were finally diagnosed with a bone or joint infection. Cultures were positive in 27/39 infected patients and in 3/18 uninfected patients (sensitivity 69%, specificity 83%). BioFire was positive in 22/39 infected patients and in none of the uninfected patients (sensitivity 56%, specificity 100%). Sensitivity for PCR panel organisms was 92% (22/24) and sensitivity for organisms identified by any microbiological modality was 69% (22/32). Gram stain results were positive in 13/39 infected patients and in none of the uninfected patients (sensitivity 33%, specificity 100%). 16S rRNA was positive in 20/28 infected patients and in 0/12 uninfected patients (sensitivity 71%, specificity 100%). Net machine time for BioFire-1h-was shorter than the mean TAT for Gram stain results, which was 4h. BioFire offered equivalent diagnostic performance with superior TAT for bone and joint infections, compared with conventional methods.