[¹⁸F]FDG PET/CT imaging in Polyarteritis Nodosa-spectrum vasculitis

Area of Science:

• Nuclear medicine
• Radiology
• Rheumatology

Background:

• Polyarteritis nodosa (PAN) is a challenging medium-vessel vasculitis.
• Diagnosis of PAN often requires invasive methods.
• [¹⁸F]FDG PET/CT (FDG PET/CT) is increasingly used in vasculitis diagnosis.

Purpose of the Study:

• To review the current evidence for FDG PET/CT in diagnosing PAN-spectrum vasculitis.
• To identify key nuclear imaging features suggestive of PAN.
• To explore the potential role of FDG PET/CT as a diagnostic biomarker.

Main Methods:

• Review of current literature on FDG PET/CT in PAN-spectrum vasculitis.
• Focus on characteristic FDG uptake patterns in arteries and muscles.
• Evaluation of imaging findings suggestive of primary and secondary PAN.

Main Results:

• FDG uptake in medium-sized arteries, particularly in extremities, is suggestive of PAN.
• A distinct "ant-farm" or "dirty muscle" pattern may indicate vasculitic myopathy in PAN.
• FDG PET/CT can reveal findings associated with secondary PAN.

Conclusions:

• FDG PET/CT demonstrates potential as a valuable imaging biomarker for PAN-spectrum vasculitis.
• Characteristic FDG uptake patterns can support PAN diagnosis, especially when other tests are inconclusive.
• Further research is needed to clarify its role in disease monitoring and relapse evaluation.