18F-FDG PET/CT for Therapy Control in Vascular Graft Infections: A First Feasibility Study

The aim of this study was to evaluate the clinical value of PET/CT with F-18-FDG for therapy control in patients with prosthetic vascular graft infections (PVGIs). Methods: In this single-center, observational, prospective cohort study, 26 patients with a median age of 66 y (range, 48-81 y) who had a proven PVGI were included. Follow up F-18-FDG PET/CT was performed at a median of 170 d (range, 89-249 d) after baseline examination. Two independent and masked interpreters measured maximum standardized uptake values to quantify metabolic activity and analyzed whole-body datasets for a secondary diagnosis (i.e., infectious foci not near the graft). The metabolic activity of the graft was correlated with clinical information and 2 laboratory markers (C-reactive protein and white blood cell count). Results: F-18-FDG PET/CT had an impact on management in all patients. In 19 of 25 patients (76%), antibiotic treatment was continued because of the results of follow-up F-18-FDG PET/CT. Antibiotic treatment was stopped or changed in 8% and 16% of patients, respectively. In 8 patients (32%), additional incidental findings were detected on follow-up F-18-FDG PET/CT and had a further impact on patient management. Only in a subgroup of patients with PVGI and no other sites of infection was a significant correlation found between the difference in C-reactive protein at the time of baseline and follow-up F-18-FDG PET/CT and the difference in maximum standardized uptake value (n = 11; R-2 = 0.67; P = 0.002). Conclusion: F-18-FDG PET/CT represents a useful tool in therapy monitoring of PVGI and has an impact on patient management.