Evaluation of vascular prosthetic graft infection by 18F-FDG PET/CT

Objective: To determine the role of 18F-FDG PET/CT in the assessment of vascular prosthetic graft infection. Method(s): Prospective cohort study with retrospective analysis. Assess to 8 patients with clinically suspected vascular prosthetic infection underwent a 18F-FDG-PET/CT scan. Angiography studies and Tc99m-HMPAO labeled leukocyte scintigraphy results were correlated with PET/CT uptake. The gold standard was based on operative/histopathological finding or a clinical follow up of >6 months. Result(s): A total of 8 patients (5 men and 3 women), with a mean age 61 +/- 13.6 years and range 38-77. The location of the graft prosthesis was: Aorto-bifemoral (5), Aorto-iliacal (1), Femoro-popliteal (1) and Thoraco-abdominal (1). Seven patients presented pathological uptake in PET/CT and according to operative/histopathological findings or a clinical follow up presented vascular prosthetic graft infection. The mean SUV max was 6.4 g/ml +/- 1.8 and range 4.0-9.0. Positive findings for infection were observed at angio-CT or angio-MRI. However, three cases evidenced negative Tc99m-HMPAO labeled leukocyte scintigraphy. Only one patient demonstrated a negative PET/CT, concordance to a normal angio- MRI and nonclinical signs of infections at follow up for one year. Conclusion(s): PET/CT-FDG is a useful tool in the diagnosis of vascular prosthetic graft infection with excellent accuracy. The concordance between angiography studies and the tomography functional scan was high; however, the Tc99m-HMPAO labeled leukocyte scintigraphy was not helpful for the detection of vascular prosthetic graft infection