The Role of PET/CT in the Investigation of Fever of Unknown Origin

Aims: Fever of unknown origin (FUO) remains a diagnostic challenge for clinicians. The current diagnostic approach includes a detailed medical history, physical examination, laboratory tests and imaging techniques (chest X-ray, ultrasound, CT, MRI). 18F-FDG PET/CT (18fluoro-deoxyglucose PET/CT) is a non-invasive diagnostic imaging technique, which is widely used in oncology. The purpose of our narrative review was to summarize the knowledge for the diagnostic role of 18F-FDG PET/CT in the diagnostic approach of patients with FUO, as reported in the literature.

Methodology: We undertook a search of literature published in PubMed until February 2019.

Results: Various studies showed that 18F-FDG PET/CT could play an important role as a second-line explorative technique in the diagnosis of patients with FUO. 18F-FDG PET/CT presents high diagnostic accuracy in large vessel vasculitis, in orthopedic prosthetic infections, in chronic osteomyelitis and in prosthetic valve endocarditis. However, 18 -FDG/PET has some limitations such as the assessment of urine tract due to the excretion into the urine but also become of the high glucose metabolism in some organs such as the brain.

Conclusions: Overall, PET/CT gains increasing interest in the diagnosis of FUO and should be considered by the clinicians in the exploration of those patients.