Large vessel vasculitis as cause of fever (FUO) or systemic inflammation of unknown origin Value of F-18 Fluorodeoxyglucose positron emission tomography (18F-FDG-PET): Diagnostik mittels 18-F-Fluor-2-deoxy-D-Glukose Positronen-Emissionstomographie (18F-FDG-PET)

Background Diagnosis and treatment of FUO or systemic inflammation with unknown reason are still a great challenge for the treating physician. We used F-18-FDG-PET for further diagnostic work in patients in whom a diagnosis could not be established despite intensive diagnostic efforts. Methods/Results We studied nine patients with F-18-FDG-PET. Two female patients with known Takayasu's arteritis but undefineable disease activity, and seven patients with the clinical suspicion of an underlying large vessel vasculitis. The diagnosis of active vasculitis could be confirmed by the PET-results in eight patients. Active vasculitis could be nearly ruled out in one. The diagnoses could be confirmed by follow-up visits. Conclusion (18)-F-FDG-PET is a useful diagnostic tool in patients with unclear systemic inflammation and FUO. Especially when large vessel vasculitis is suspected, further diagnostic work by PET seems to be of benefit. Furthermore, it offers the opportunity to evaluate disease activity and to check which vessels are involved.