Getting a hip or knee implant can ease pain and improve a person's quality of life tremendously — and it can also introduce a deadly bacterial infection. Identifying and pinpointing infections in introduced biomaterial, such as implants, can be difficult, and effective treatment is sometimes delayed due to misdiagnosis. Infections following implant surgeries are often mistaken for normal, post-op inflammation. But a team publishing their report today in Nature Communications found that low doses of a fluorescent antibiotic can accurately track bacterial infection in real-time.
The team infected a mouse with two different strains of bacteria, Escherichia coli and Staphylococcus aureus. To track the accuracy of the antibiotic, both strains of bacteria were engineered to be bioluminescent (in blue in photo above). They then injected the antibiotic vancomycin, also modified to be fluorescent (red in photo above), into the mouse.
As the video below shows, the fluorescent vancomycin zeroed in on the areas of bacterial infection within hours. In subsequent experiments, the vancomycin did not target areas of sterile, non-bacterial inflammation induced in other models by the researchers.
Because the amount of fluorescent vancomycin injected is well below the therapeutic dose of the drug, researchers say the approach is non-invasive; it could allow doctors to diagnose and locate infections in real-time and then begin appropriate treatment before serious complications arise.