Innovative Bacteria-Targeted PET Imaging Detects Difficult Lung Infections

A breakthrough in medical imaging has introduced a new PET (Positron Emission Tomography) technique capable of specifically detecting lung infections caused by Mycobacteroides abscessus, one of the most challenging bacterial infections to diagnose. Traditionally, distinguishing bacterial infections like M. abscessus from inflammation in lung diseases such as cystic fibrosis or chronic obstructive pulmonary disease has been difficult using conventional imaging methods. These standard tools cannot reliably differentiate bacterial infections from other inflammatory processes, often necessitating invasive procedures for definitive diagnosis.

The latest approach employs a novel radiotracer, ¹¹C-PABA, which selectively accumulates in the bacteria, enabling precise visualization of the infection sites. This technique was evaluated in both laboratory and clinical settings. In vitro studies confirmed ¹¹C-PABA’s affinity for M. abscessus bacteria, and animal models demonstrated sustained tracer accumulation in infected lung tissues. The clinical application involved a patient with cystic fibrosis and microbiologically proven M. abscessus lung infection, where dynamic ¹¹C-PABA PET scans showed significantly higher tracer uptake in infected regions compared to healthy lung tissue.

Presented at the 2025 Society of Nuclear Medicine and Molecular Imaging Annual Meeting and published in the Journal of Nuclear Medicine, this innovation offers a promising, noninvasive, bacteria-specific diagnostic tool. It could transform how clinicians diagnose and monitor difficult bacterial lung infections, allowing for more targeted treatments and improved patient outcomes.

"Given the limitations of current imaging methods, developing bacteria-specific imaging agents like ¹¹C-PABA PET is a critical step forward," said researcher Dr. Yuderleys Masias-Leon. "This technique has the potential to enable rapid, accurate diagnosis, guiding personalized and more effective treatment strategies."

The study highlights the possibility of using this new imaging modality to facilitate early diagnosis and monitor treatment responses, especially crucial for immunocompromised patients or those with chronic lung conditions affected by resistant bacterial strains.