A recent Mayo Clinic study was conducted to assess whether the FilmArray Blood Culture ID (BCID) panel, from BioMérieux subsidiary BioFire Diagnostics, can be used to determine the cause of prosthetic joint infection (PJI). The panel detects 24 pathogens and three antibiotic resistance genes associated with bloodstream infections. The study was recently published in the Journal of Clinical Microbiology.
GenomeWeb recently interviewed Robin Patel, corresponding author on the independent study and chair of the division of clinical microbiology at the Mayo Clinic, about the study. Dr. Patel said, "We had previously shown that a panel of PCR assays targeting the organisms that cause PJI was a sensitive and specific way to diagnose infection.”
According to the article, as many as two percent of prosthetic joint implants each year in the U.S. will become infected because determining PJI is difficult. The particular bacterial culprits often form biofilms on the surfaces of medical implants or devices.
Mayo Clinic researchers are pioneering the use of vortexing and sonication to shake the films loose and separate the clumps, thus improving yield of bacteria.
In the study, the team looked at 216 frozen samples of sonicate fluids from an archive, 98 of which were known PJI cases and 118 were aseptic joint failures. The overall sensitivity of BCID to detect the cases was 53 percent, compared to 69 percent for culture. The panel specificity, meanwhile, was 99 percent.
According to the study results, a BCID-like approach would possibly be a useful adjunct to PJI diagnosis provided the sensitivity for coagulase negative bacteria were increased, and additional PJI-related pathogens, as well as perhaps a universal 16S rRNA target, were added.
"If this works, it could potentially be applied to synovial fluid, which could be aspirated in the office and quickly tested in a nearby laboratory, even while the patient waits," Patel said.