Imaging of immunocompromised patients: focus on fungal-specific PET tracers

Area of Science:

• Medical Imaging
• Infectious Diseases
• Nuclear Medicine

Background:

• Growing population of immunocompromised individuals leads to increased opportunistic infections.
• Invasive mold infections pose significant morbidity and mortality due to diagnostic challenges.
• Current diagnostic methods for invasive fungal infections lack specificity or are invasive.

Purpose of the Study:

• To review novel noninvasive positron emission tomography (PET) imaging ligands for diagnosing invasive mold infections.
• To highlight the potential of specific PET tracers in improving diagnostic accuracy and treatment monitoring.
• To discuss the advantages of newer PET ligands over existing methods like [18F]-fluorodeoxyglucose (FDG).

Main Methods:

• Evaluation of novel PET imaging ligands, including [18F]-fluorocellobiose.
• Assessment of ImmunoPET approaches targeting fungal cell wall components.
• Discussion of enzymatic synthesis and antibody engineering for PET ligand optimization.

Main Results:

• [18F]-fluorocellobiose demonstrates high specificity for live cellulolytic mold infections, including Aspergillus spp.
• Novel PET ligands show potential for accurate localization and differentiation of fungal infections.
• ImmunoPET offers a promising panfungal approach with potential for optimization.

Conclusions:

• New PET imaging ligands can overcome limitations of [18F]-FDG, improving diagnosis of invasive fungal infections.
• Accurate and rapid diagnosis using advanced PET tracers is crucial for patient outcomes.
• These advancements are significant for the vulnerable immunocompromised patient population.