FDG PET/CT in evaluation of pyrexia of unknown origin

Area of Science:

• Medical imaging
• Diagnostic medicine
• Nuclear medicine

Background:

• Pyrexia of unknown origin (PUO) is defined as fever >38.5°C for 3 weeks with inconclusive investigations.
• Tuberculosis and human immunodeficiency virus (HIV) infection are significant causes of PUO.
• Malignancy, bacterial infections, sarcoidosis, and autoimmune disorders are other potential etiologies.

Observation:

• Standard investigations like blood tests, imaging (radiography, CT, MRI), and cultures are often insufficient for PUO diagnosis.
• Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) is increasingly utilized in complex diagnostic scenarios.
• This atlas presents cases where conventional methods failed, but FDG-PET/CT pinpointed the pathology.

Findings:

• FDG-PET/CT demonstrated the site of pathology in cases of PUO where initial investigations were inconclusive.
• The imaging modality guided subsequent histologic diagnosis, confirming the underlying cause.
• FDG-PET/CT proved valuable in identifying diverse pathologies contributing to PUO.

Implications:

• FDG-PET/CT offers a powerful tool for diagnosing challenging cases of PUO.
• Early and accurate diagnosis through advanced imaging can lead to timely and appropriate treatment.
• This approach can potentially reduce diagnostic delays and improve patient outcomes in unexplained fever cases.