Stanford develops novel PET tracer to ID most bacterial infections

Bacteria are experts at mutating to become resistant to any antibiotic treatment. With no promise of stagnation, it is no wonder that the Centers for Disease Control and Prevention (CDC) has called for medical scientists to develop new novel diagnostics to detect and help regulate the treatment of infections and infectious diseases.

A new study featured in the October issue of The Journal of Nuclear Medicine describes how Stanford University scientists developed a novel imaging agent that could be used to detect most bacterial infections and monitor antibiotic treatment.

"We really lack tools in the clinic to be able to visualize bacterial infections," explained Sanjiv Sam Gambhir, MD, PhD, and chair of the radiology department and director of Precision Health. "What we need is something that bacteria eat that your cells, so-called mammalian cells, do not. As it turns out, there is such an agent, and that agent is maltose, which is taken up only by bacteria because they have a transporter, called a maltodextrine transporter, on their cell wall that is able to take up maltose and small derivatives of maltose."

According to the Society of Nuclear Medicine and Molecular Imaging, Gambhir and his fellow colleagues developed a new positron emission tomography (PET) tracer, 6"-18F-fluoromaltotriose. Unlike traditionally diagnosing bacterial infections with a biopsy of the infected tissue, this approach offers non-invasive detection of bacterial infections for the patient.

"For this study, the tracer was evaluated in several clinically relevant bacterial strains in cultures and in mouse models using a micro-PET/CT scanner. Its use to help monitor antibiotic therapies was also evaluated in rats," according to the Society of Nuclear Medicine and Molecular Imaging.

Results of the study show that 6"-18F-fluoromaltotriose may be the best agent in diagnosing most bacterial infections and diseases and ultimately will change the clinical management in doing so.

"The hope is that in the future when someone has a potential infection, this approach of injecting the patient with fluoromaltotriose and imaging them in a PET scanner will allow localization of the signal and, therefore, the bacteria," Gambhir said. "And then, as one treats them, one can verify that the treatment is actually working—so that if it's not working, one can quickly change to a different treatment (for example, a different antibiotic). These kinds of findings are very important for patients, because they will very likely lead to entirely new ways to manage patients with bacterial infections, no matter where those infections might be hiding in the body."

The entire study is available here.