Clinical value of Time of Flight FDG-PET/CT in detecting of infection and inflammation

The purpose of this study was to assess the value of Time of Flight FDG-PET/CT in detecting of infection and inflammation. This study is a retrospective analysis of the data from 115 patients (m = 71, f = 44) with a suspected diagnosis of infection or inflammation examined with 18F-FDG-PET/CT in the nuclear medicine department of the University Medical Centre Göttingen (UMG) during 2009 to 2012. The results of 18F-FDG-PET/CT scans were compared with the results of histological, bacteriological, serological, radiological and endoscopic techniques and the final clinical diagnosis. Follow-up for 3 months was mandatory for inclusion into the retrospective analysis. All patients were examined with FDG-PET/CT (Gemini TF, Philips, Germany). 72 patients received additional contrast-enhanced CT. The sensitivity in the total patient group was 83% and the specificity 89 %, respectively. The positive predictive value was 94 % and the negative predictive value 72 %. In 52 patients (45 %) the FDG-PET/CT was helpful in establishing the final diagnosis. Sensitivity and specificity in patients with prolonged fever of unknown origin (n = 32) were 70 % and 100 %. The positive predictive value was 100 % and the negative predictive value 56 %. In 12 patients (38 %) the FDG-PET/CT was helpful in establishing the final diagnosis. The sensitivity and specificity in patients with inflammation of unknown origin (n = 44) were 88 % and 70 %. The positive predictive value was 91 % and the negative predictive value 64 %. In 23 patients (52 %) the FDG-PET/CT was helpful in establishing the final diagnosis. In the group of patients with large vessel vasculitis (n = 15) was a sensitivity of 67 % and a specificity of 100 % found. The positive predictive value was 100 % and the negative predictive value 82 %. In 6 patients (40 %) the FDG-PET/CT was helpful in establishing the final diagnosis. In the group of patients with musculoskeletal infections (n = 24) the sensitivity was 100 % and the specificity 89 %. The positive predictive value was 94 % and the negative predictive value 100 %. In 11 patients (46 %) the FDG-PET/CT was helpful in establishing the final diagnosis. Conclusions: FDG-PET/CT is a valuable imaging technique in patients with fever and inflammation of unknown origin and in the diagnosis of vasculitis and musculoskeletal infections. In comparison to the published FDG-PET data the number of conclusive findings was tendentially higher.2017-02-0