Aim: To evaluate the value of 18F-FDG (positron emission tomography) PET/CT in assessment patients with fever of unknown origin (FUO) and to compare the findings with the results of the other investigations. Patients and methods: This is perspective study in which 27 patients having FUO underwent 18F-FDG-PET/CT examination, using combined PET/CT with contrast enhanced CT. PET/CT findings were compared with the results of biopsies, immunology, or microbiology around the examination period & for the following 3 month duration, during which patients with negative PET/CT findings were followed also. Results: The cause of FUO was explained according to the PET/CT findings and the other investigations in 27 patients: 6 patients with infections, 2 patients with autoimmune inflammation, 3 patients with solid malignancies, 2 patients with sarcoidosis, 6 patients with vasculitis, 5 patients with lymphoproliferative disease & 3 patients with negative findings. PET/CT findings matched the clinical diagnosis in 23 patients, 4 patients showed negative PET/CT findings (2 patients as true negative & the other 2 patients as false negative that were fatherly diagnosed as lymphoma). The examination sensitivity 95%, specificity 67%. Conclusion: 18F FDG PET/CT can be a useful tool for scanning the whole body to suggest the FUO cause.
