Positron emission tomography assessment of large vessel inflammation in patients with newly diagnosed, biopsy-proven giant cell arteritis: a prospective, case-control study

Ann Rheum Dis. 2014 Jul;73(7):1388-92. doi: 10.1136/annrheumdis-2013-204572. Epub 2014 Mar 24.


Background: Positron emission tomography (PET) scan is emerging as a promising imaging technique to detect large-vessel inflammation in giant cell arteritis (GCA). However, the lack of a standardised definition of arteritis based on (18)fluorodeoxyglucose (FDG) uptake is an important limitation to the use of PET scan for diagnostic purposes.

Objective: To prospectively assess the intensity and distribution of FDG uptake at different vascular territories in patients with newly diagnosed GCA compared with controls.

Methods: 32 consecutive, biopsy-proven, GCA patients treated with glucocorticoids for ≤3 days were included. The control group consisted of 20 individuals, who underwent PET/CT for cancer staging. Maximal standardised uptake value (SUVm) was calculated at four aortic segments, supraaortic branches and iliac-femoral territory. Sensitivity and specificity was calculated by receiver-operator characteristic curves (ROC) analysis.

Results: Mean SUVm was significantly higher in patients than in controls in all vessels explored and correlated with acute-phase reactants and serum IL-6. Mean of the SUVm at all the vascular territories had an area under the curve (AUC) of 0.830, and a cut-off of 1.89 yielded a sensitivity of 80% and a specificity of 79% for GCA diagnosis. There were no significant differences in AUC among the vascular beds examined.

Conclusions: FDG uptake by large vessels has a substantial sensitivity and specificity for GCA diagnosis.

Keywords: acute-phase reactants; diagnosis; giant-cell arteritis; imaging; inflammation; interleukin-6; large-vessel vasculitis; positron-emission tomography.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acute-Phase Proteins / immunology
  • Aged
  • Aged, 80 and over
  • Aorta / diagnostic imaging
  • Area Under Curve
  • Arteries / diagnostic imaging*
  • Arteries / pathology
  • Axillary Artery / diagnostic imaging
  • Biopsy
  • Carotid Arteries / diagnostic imaging
  • Case-Control Studies
  • Female
  • Femoral Artery / diagnostic imaging
  • Fluorodeoxyglucose F18
  • Giant Cell Arteritis / diagnostic imaging*
  • Giant Cell Arteritis / immunology
  • Giant Cell Arteritis / pathology
  • Humans
  • Iliac Artery / diagnostic imaging
  • Interleukin-6 / immunology
  • Male
  • Middle Aged
  • Multimodal Imaging
  • Positron-Emission Tomography
  • Prospective Studies
  • ROC Curve
  • Radiopharmaceuticals
  • Sensitivity and Specificity
  • Subclavian Artery / diagnostic imaging
  • Temporal Arteries / pathology
  • Tomography, X-Ray Computed


  • Acute-Phase Proteins
  • Interleukin-6
  • Radiopharmaceuticals
  • Fluorodeoxyglucose F18