News | PET-CT | January 22, 2018

Novel PET Tracer Clearly Identifies and Tracks Bacterial Lung Infection

PET tracer 18F-FDS effectively tracks the degree of bacterial infection and can better differentiate infection from inflammation than other tracers tested

Novel PET Tracer Clearly Identifies and Tracks Bacterial Lung Infection

Representative PET/CT images of 18F-FDS and 18F-FDG in inflamed mice. Mice were inoculated with dead K. pneumoniae (10^8 CFU/mL). Imaging was performed for days 1, 2, 3 and 4 using 18F-FDG and 18F-FDS. CT images showed clear inflammation on day 2 and day 3 with corresponding high 18F-FDG uptake on PET. No significant uptake of 18F-FDS was detected for any of those 4 days. Credit: J Li et al., University of Louisville School of Medicine, Louisville, Ky.

January 22, 2018 — Researchers at the University of Louisville, Kentucky, have demonstrated that a new radiotracer, 2-18F-fluorodeoxysorbitol (18F-FDS), can identify and track bacterial infection in lungs better than current imaging methods and is able to differentiate bacterial infection from inflammation. The study is the featured basic science article in the January issue of The Journal of Nuclear Medicine.

“Currently, bacterial infections can be diagnosed only after they have become systemic or have caused significant anatomical tissue damage, a stage at which they are challenging to treat owing to the high bacterial burden,” explained Chin K. Ng, Ph.D., at the University of Louisville School of Medicine.

He pointed out, “18F-FDG PET, a widely commercially available imaging agent, is capable of imaging infection, but it cannot distinguish infections from other pathologies such as cancer and inflammation. Therefore, there is a great need to develop imaging agents with high specificity and sensitivity. There are still no specific imaging agents that can differentiate bacterial infection from sterile inflammation at an early stage.”

For this study, mice were inoculated with either live Klebsiella pneumoniae bacteria to induce lung infection, or the dead form of the bacteria to induce inflammation. Half of the mice with the live bacteria were imaged with positron emission tomography (PET)/computed tomography (CT) using either 18F-FDS or 18F-FDG on days 0, 1, 2 and 3 to monitor disease progression post-infection. The other half were screened by bioluminescent imaging, and mice with visible infection were selected for follow-up PET/CT scans with 18F-FDS. For the inflammation group, half the mice were imaged with PET/CT using 18F-FDS and half using 18F-FDG from day 1 to day 4 post-inoculation.

While both 18F-FDS and 18F-FDG effectively tracked the degree of bacterial infection measured by bioluminescent optical imaging, only 18F-FDS was able to differentiate lung infection from lung inflammation.

Ng noted, “Bacterial infection represents a threat to human health, including hospital-acquired, implant-related, and multidrug-resistant infections. 18F-FDS whole-body PET/CT imaging in mice has shown to be a unique imaging technique that could differentiate infection from inflammation. This same technique could potentially be used in patients to identify infection sites and determine the bacterial infection class, so that patients could avoid taking antibiotics that are known to have no effect against specific bacteria.”

He added, “The interpretation of CT appearances of lung disorders can be complex if a differential diagnosis needs to distinguish between inflammation and infection. Thus 18F-FDS PET/CT could be initially used as a follow up after an inconclusive CT diagnosis for suspected bacterial lung infection. As proven clinical data accumulate over time, 18F-FDS PET/CT could become a new clinical standard for confirming bacterial infection in the lungs or other sites.”

Looking ahead to making 18F-FDS clinically available, Ng stated, “Since 18F-FDS can be made from 18F-FDG with one extra, simple conversion step, and sorbitol has already been approved for use in humans by the U.S. Food and Drug Administration, the approval pathway for 18F-FDS should be straightforward. 18F-FDS would be inexpensive and readily available once approved.”

He also observed, “This and other new PET imaging agents demonstrate that molecular imaging and nuclear medicine can offer unique technologies for patient care and will continue to play a key influential role in healthcare.”

For more information: www.jnm.snmjournals.org

 

Related Content

The interior of the German air force Airbus A-310 Medivac in Cologne, Germany, before its departure to Bergamo, Italy, March 28 to being ferrying COVID-19 patients to Germany for treatment to aid the Italians, whose healthcare system has been overwhelmed by the rapid spread of the coronavirus pandemic. Bundeswehr Photo by Kevin Schrief.

The interior of the German air force Airbus A-310 Medivac in Cologne, Germany, before its departure to Bergamo, Italy, March 28 to being ferrying COVID-19 patients to Germany for treatment to aid the Italians, whose healthcare system has been overwhelmed by the rapid spread of the coronavirus pandemic. Bundeswehr Photo by Kevin Schrief. Find more images from the COVID-19 pandemic.

 

Feature | Coronavirus (COVID-19) | April 08, 2020 | By Melinda Taschetta-Millane and Dave Fornell
In an effort to keep the imaging field updated on the latest information being released on coronavirus (COVID-19), th
Recommended best practices for nuclear imaging departments under the COVIF-19 pandemic have been issues by the ASNC and SNMMI. #COVID19 #ASNC #SNMMI #Coronavirus #SARScov2
News | Coronavirus (COVID-19) | April 03, 2020
April 3, 2020 — A new guidance document on best practices to maintain safety and minimize contamination in nuclear im
Novel scanners may open door for prognostic assessment in patients receiving cochlear implants

Iva Speck, MD, explains research showing that novel, fully digital, high-resolution positron emission tomography/computed tomography imaging of small brain stem nuclei can provide clinicians with valuable information concerning the auditory pathway in patients with hearing impairment. The research is featured in The Journal of Nuclear Medicine (read more at http://jnm.snmjournals.org/content/current). Video courtesy of Iva Speck, University Hospital Freiburg, Germany.

News | PET-CT | March 26, 2020
March 26, 2020 — Novel, fully digital, high-resolution...
A University of Colorado Cancer Center study published in the Journal of the National Cancer Institute shows an important predictor of PET-CT use

Rustain Morgan, M.D., and colleagues show racial/ethnic disparities in use of important imaging during lung cancer diagnosis. Photo courtesy of University of Colorado Cancer Center

News | PET-CT | March 12, 2020
March 12, 2020 — The use of PET-CT
 “Cyclotrons used in Nuclear Medicine Report & Directory, Edition 2020” that describes close to 1,500 medical cyclotrons worldwide
News | Nuclear Imaging | March 10, 2020
March 10, 2020 — MEDraysintell released its new and unique report “...
MR Solutions’ dry magnet MRI system for molecular imaging on display at EMIM 2020
News | Magnetic Resonance Imaging (MRI) | February 28, 2020
February 28, 2020 — MR Solutions will be displaying its la
Potassium Molybdate Mo 99 Source Vessels for RadioGenix System

Potassium Molybdate Mo 99 Source Vessels for RadioGenix System (Photo: Business Wire)

News | Radiopharmaceuticals and Tracers | February 18, 2020
February 18, 2020 — NorthStar Medical Radioisotopes, LLC, a