18-Fluorodeoxyglucose-PET/CT Imaging of Lungs in Patients With Cystic Fibrosis.

Chest. 2009 Aug 20; Klein M, Cohen-Cymberknoh M, Armoni S, Shoseyov D, Chisin R, Orevi M, Freedman N, Kerem EBACKGROUND: Airway inflammation plays a critical role in the progression of cystic fibrosis (CF) lung disease and in the destruction of airways and lung parenchyma. Current methods to assess CF lung disease, (BAL, spirometry, HRCT), do not always accurately reflect actual disease states. FDG-PET has previously been used to image infection and inflammation. Here we assessed the use of (18)F-FDG PET/CT to evaluate and monitor lung inflammation and/or infection in CF. METHODS: PET/CT scans were performed on 20 patients with CF (ages 14-54 years), 7/20 underwent repeat PET/CT during and after acute exacerbations. Results were compared with clinical information, and with images of 8 control subjects with no known lung disease. RESULTS: Foci of enhanced activity were observed on FDG-PET of CF patients but not controls. Higher focal activity (SUV > 3.0) was seen during disease exacerbation and infection. Co-registered CT images assisted in localization of PET foci and showed corresponding CT findings, with many additional findings on CT not seen on PET. High intensity PET foci seen during exacerbations disappeared after antibiotic therapy and resolution of exacerbation, while corresponding CT findings remained unchanged. CONCLUSION: PET/CT imaging demonstrated the presence of foci of enhanced uptake that may reflect active focal infectious or inflammatory processes in the lungs. These foci can be cleared with antibiotic therapy. Further studies are needed to validate these results and to determine if FDG-PET/CT can predict the nature/severity of disease in patients with CF.