Positron Emission Tomography Applications in Tuberculosis Diagnosis

Positron emission tomography (PET) has emerged as a powerful non-invasive tool for the diagnosis, staging and therapeutic monitoring of tuberculosis (TB). By visualising metabolic processes in three dimensions, PET complements conventional methods such as sputum microscopy and radiography, which often miss early or extrapulmonary disease. The most widely used PET tracer, 18F-fluorodeoxyglucose (18F-FDG), accumulates in activated immune cells at sites of infection, providing detailed maps of lesion distribution and activity. Recent advances have sought to overcome the lack of pathogen specificity of 18F-FDG by developing tracers that exploit unique mycobacterial metabolic pathways, enabling direct imaging of viable Mycobacterium tuberculosis. Integration with computed tomography (CT) or magnetic resonance imaging (MRI) affords precise anatomical localisation of tuberculous lesions, while quantitative PET metrics—such as standard uptake values and volumetric glycolytic activity—offer reproducible biomarkers for treatment response. These capabilities are particularly valuable in drug-resistant and extrapulmonary TB, where conventional endpoints may be unreliable. Ongoing efforts to streamline radiopharmaceutical production and validate novel tracers in preclinical models are paving the way for clinical translation and global implementation of TB-specific PET imaging.

Research from Nature Portfolio

Researchers have introduced a trehalose-based tracer, 2-[18F]fluoro-2-deoxytrehalose (18F-FDT), which is selectively processed by Mycobacterium tuberculosis enzymes. In preclinical studies including non-human primates, 18F-FDT enabled high-contrast visualisation of TB lesions and real-time monitoring of antibiotic efficacy. A scalable, enzyme-catalysed synthesis from the widely available clinical reagent 18F-FDG supports potential global deployment of this bacterium-selective tracer.

Another study has explored a radiolabelled puromycin analogue, [68Ga]Ga-DOTA-puromycin, for imaging in vivo protein synthesis during mycobacterial infection via combined micro-PET/MRI. In immunodeficient mouse models, the tracer reliably detected sites of active infection and correlated with histopathological measures of bacterial viability. Although selective for infection over sterile inflammation, the analogue accumulated in multiple bacterial species, underscoring the need for further refinement of pathogen specificity.

Positron Emission Tomography Applications in Tuberculosis Diagnosis publication trend

The graph below shows the total number of articles in positron emission tomography applications in tuberculosis diagnosis across all publications each year (not limited to Nature Index journals).

Technical terms

Positron Emission Tomography (PET): A functional imaging technique that detects gamma rays emitted by a positron-emitting tracer to map metabolic processes in vivo.

Fluorodeoxyglucose (18F-FDG): A glucose analogue radiotracer that accumulates in active inflammatory cells and is widely used to visualise infection sites.

2-[18F]fluoro-2-deoxytrehalose (18F-FDT): A trehalose-based PET tracer metabolised by Mycobacterium tuberculosis, enabling selective imaging of bacterial lesions.

Standard Uptake Value (SUV): A quantitative measure of tracer concentration in tissue, normalised for injected dose and patient body weight.

Computed Tomography (CT): An anatomical imaging modality that uses X-rays to produce cross-sectional images of the body’s internal structures.

Radiopharmaceutical: A chemical compound labelled with a radioactive isotope used for diagnostic imaging or targeted therapy.

References

1. Distributable, metabolic PET reporting of tuberculosis. Nature Communications (2024).
2. Visualisation of in vivo protein synthesis during mycobacterial infection through [68Ga]Ga-DOTA-puromycin µPET/MRI. Scientific Reports (2024).
3. FDG-PET-CT as an early detection method for tuberculosis: a systematic review and meta-analysis. BMC Public Health (2024).
4. Tuberculous Spondylodiscitis with Psoas Abscess Descending into the Anterior Femoral Compartment Identified Using 2-deoxy-2-[18F]fluoroglucose Positron Emission Tomography Computed Tomography. Diagnostics (2024).
5. Quantitative 18F-FDG PET-CT scan characteristics correlate with tuberculosis treatment response. EJNMMI Research (2020).
6. A semi-automatic technique to quantify complex tuberculous lung lesions on 18F-fluorodeoxyglucose positron emission tomography/computerised tomography images. EJNMMI Research (2018).