title: FDG Uptake by Prosthetic Arterial Grafts in Large Vessel Vasculitis Is Not Specific for Active Disease.
abstract: This study investigated the incidence and clinical significance of arterial graft-associated uptake of fluorodeoxyglucose in large-vessel vasculitis (LVV).
  
  
  
  The role of18F-labeled fluorodeoxyglucose-positron emission tomography/computed tomography ([18F]FDG-PET/CT) in the management of LVV remains to be defined. Although [18F]FDG uptake at arterial graft sites raises concerns regarding active arteritis or infection, its clinical significance in LVV has never been formally studied.
  
  
  
  An observational prospective study sought to identify patients with Takayasu arteritis (TA) undergoing [18F]FDG-PET/CT more than 6 months after graft surgery from a large cohort of patients from 2 tertiary referral centers. [18F]FDG uptake by the graft and native arteries was scored on a scale of 0 to 3 relative to hepatic uptake, and periprosthetic maximum standardized uptake value (SUVmax) was calculated. Periprosthetic [18F]FDG uptake in active disease was compared with that in inactive disease, and arterial progression was assessed by prospective magnetic resonance angiography (MRA).
  
  
  
  Twenty-six subjects with TA were enrolled. All were afebrile with negative blood culture. Periprosthetic uptake was significant in 23 of 26 patients, and the mean SUVmaxwas 4.21 ± 1.46. Median periprosthetic [18F]FDG uptake score (3; interquartile range [IQR]: 3 to 3) was higher than in native aorta (1; IQR: 0 to 1; p < 0.001). Graft-specific [18F]FDG uptake was unrelated to disease activity. Despite the high frequency of graft-associated [18F]FDG uptake, sequential MRAs did not reveal arterial progression in 25 of 26 patients; the 1 remaining case showed minor progression limited to native arteries. Nine patients underwent repeated PET/CT scanning without showing changes in graft-specific uptake, despite increased treatment.
  
  
  
  Significant [18F]FDG uptake that is confined to arterial graft sites in patients with LVV does not reflect clinically relevant disease activity or progression. To minimize exposure to immunosuppression and in the face of negative blood culture, clinically quiescent arteritis, normal or stably raised C-reactive protein levels, we elected not to escalate treatment and monitor progression with MRA.
authors.affiliation: Cardiovascular Sciences and Rheumatology Units, Imperial College Healthcare National Health Service Trust, London, United Kingdom.
authors.forename: Taryn
authors.initials: T
authors.lastname: Youngstein
authors.affiliation: Cardiovascular Sciences and Rheumatology Units, Imperial College Healthcare National Health Service Trust, London, United Kingdom; Unit of Internal Medicine and Clinical Immunology, IRCCS San Raffaele Scientific Institute, Milan, Italy.
authors.forename: Enrico
authors.initials: E
authors.lastname: Tombetti
authors.affiliation: Cardiovascular Sciences and Rheumatology Units, Imperial College Healthcare National Health Service Trust, London, United Kingdom.
authors.forename: Jaita
authors.initials: J
authors.lastname: Mukherjee
authors.affiliation: Imaging Department, Imperial College Healthcare National Health Service Trust, London, United Kingdom; Division of Cancer and Surgery, Imperial College London, London, United Kingdom.
authors.forename: Tara D
authors.initials: TD
authors.lastname: Barwick
authors.affiliation: Imaging Department, Imperial College Healthcare National Health Service Trust, London, United Kingdom; Division of Cancer and Surgery, Imperial College London, London, United Kingdom.
authors.forename: Adil
authors.initials: A
authors.lastname: Al-Nahhas
authors.affiliation: Prince Charles Hospital, Merthyr Tydfil, Wales.
authors.forename: Emyr
authors.initials: E
authors.lastname: Humphreys
authors.affiliation: Rheumatology Unit, University Hospital Wales, Cardiff, Wales.
authors.forename: Julian
authors.initials: J
authors.lastname: Nash
authors.affiliation: Rheumatology Unit, Chapel Allerton Hospital, Leeds, United Kingdom.
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Andrews
authors.affiliation: Unit of Nuclear Medicine, IRCCS San Raffaele Scientific Institute, Milan, Italy; University of Milan, Milan, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Incerti
authors.affiliation: Unit of Internal Medicine and Clinical Immunology, IRCCS San Raffaele Scientific Institute, Milan, Italy; Vita-Salute San Raffaele University, Milan, Italy.
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Tombolini
authors.affiliation: Vita-Salute San Raffaele University, Milan, Italy; Unit of Radiology, IRCCS San Raffaele Scientific Institute, Milan, Italy.
authors.forename: Annalaura
authors.initials: A
authors.lastname: Salerno
authors.affiliation: Unit of Internal Medicine and Clinical Immunology, IRCCS San Raffaele Scientific Institute, Milan, Italy; Vita-Salute San Raffaele University, Milan, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Sartorelli
authors.affiliation: Unit of Internal Medicine and Clinical Immunology, IRCCS San Raffaele Scientific Institute, Milan, Italy; Vita-Salute San Raffaele University, Milan, Italy.
authors.forename: Giuseppe A
authors.initials: GA
authors.lastname: Ramirez
authors.affiliation: Unit of Radiology-Ville Turro, IRCCS San Raffaele Scientific Institute, Milan, Italy.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Papa
authors.affiliation: Unit of Internal Medicine and Clinical Immunology, IRCCS San Raffaele Scientific Institute, Milan, Italy; Vita-Salute San Raffaele University, Milan, Italy.
authors.forename: Maria Grazia
authors.initials: MG
authors.lastname: Sabbadini
authors.affiliation: Unit of Nuclear Medicine, IRCCS San Raffaele Scientific Institute, Milan, Italy.
authors.forename: Luigi
authors.initials: L
authors.lastname: Gianolli
authors.affiliation: Vita-Salute San Raffaele University, Milan, Italy; Unit of Radiology, IRCCS San Raffaele Scientific Institute, Milan, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: De Cobelli
authors.affiliation: Unit of Nuclear Medicine, IRCCS San Raffaele Scientific Institute, Milan, Italy.
authors.forename: Federico
authors.initials: F
authors.lastname: Fallanca
authors.affiliation: Unit of Internal Medicine and Clinical Immunology, IRCCS San Raffaele Scientific Institute, Milan, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Baldissera
authors.affiliation: Unit of Internal Medicine and Clinical Immunology, IRCCS San Raffaele Scientific Institute, Milan, Italy; Vita-Salute San Raffaele University, Milan, Italy.
authors.forename: Angelo A
authors.initials: AA
authors.lastname: Manfredi
authors.affiliation: Unit of Nuclear Medicine, IRCCS San Raffaele Scientific Institute, Milan, Italy.
authors.forename: Maria
authors.initials: M
authors.lastname: Picchio
authors.affiliation: Cardiovascular Sciences and Rheumatology Units, Imperial College Healthcare National Health Service Trust, London, United Kingdom. Electronic address: justin.mason@imperial.ac.uk.
authors.forename: Justin C
authors.initials: JC
authors.lastname: Mason
mesh_terms: D000293:Adolescent; D000328:Adult; D001158:Arteries / Q000000981:diagnostic imaging* / Q000601:surgery*; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation*; D003430:Cross-Sectional Studies; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000008:administration & dosage*; D006801:Humans; D007558:Italy; D008131:London; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D000072078:Positron Emission Tomography Computed Tomography; D011237:Predictive Value of Tests; D011446:Prospective Studies; D019275:Radiopharmaceuticals / Q000008:administration & dosage*; D062606:Tertiary Care Centers; D013997:Time Factors; D016896:Treatment Outcome; D014657:Vasculitis / Q000000981:diagnostic imaging* / Q000209:etiology; D055815:Young Adult
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: MR angiography; Takayasu arteritis; arterial graft; large-vessel vasculitis; positron emission tomography