18F-FDG PET/CT for the detection of large vessel vasculitis in patients with polymyalgia rheumatica

Purpose: Polymyalgia rheumatica (PMR) may present together with large vessel vasculitis (LVV), and frequently requires a more intensive therapy. The aim of the study was to evaluate the impact of F-18-FDG PET/CT in the diagnosis and management of LVV associated to PMR. Material and methods: This prospective study included 40 consecutive patients (27 women/13 men, 68.10 +/- 10.27 years) with PMR and suspicion of associated LVV submitted for F-18-FDG PET/CT. A PET/CT scan was obtained 180 min after F-18-FDG intravenous injection. A visual analysis was performed on the images. Five vascular regions were evaluated: supra-aortic trunks (SAT), thoracic aorta (TA), abdominal aorta (AA), iliac arteries (IA), and femoral/tibioperoneal arteries (FTA). The intensity of uptake was graded from 0 to 3. A final diagnosis of LVV was established in 26/40 patients (65%). Results: In the 26 patients with a diagnosis of LVV, the highest intensity of F-18-FDG uptake was observed in the TA, SAT, and FTA. All of these patients showed uptake at the TA, with grade 2 and 3 in most cases. In 4 of the 14 patients without LVV, no uptake was observed in any vascular region, and in the other 10 patients only a grade 1 uptake was observed in 1 or to 2 territories. Out of the 20 treated LVV patients, F-18-FDG PET/CT led to a therapeutic change in 17 (85%). Conclusion: F-18-FDG PET/CT was useful in identifying patients with LVV associated to PMR. The detection of vascular inflammation had an important impact, and led to a change of treatment in a high percentage of patients with LVV. (C) 2015 Elsevier Espana, S.L.U. and SEMNIM. All rights reserved.