ACR Meeting Abstracts

ACR Meeting Abstracts

  • Meetings
    • ACR Convergence 2024
    • ACR Convergence 2023
    • 2023 ACR/ARP PRSYM
    • ACR Convergence 2022
    • ACR Convergence 2021
    • ACR Convergence 2020
    • 2020 ACR/ARP PRSYM
    • 2019 ACR/ARP Annual Meeting
    • 2018-2009 Meetings
    • Download Abstracts
  • Keyword Index
  • Advanced Search
  • Your Favorites
    • Favorites
    • Login
    • View and print all favorites
    • Clear all your favorites
  • ACR Meetings

Abstract Number: 797

PET/CT for the Diagnosis of Giant Cell Arteritis: A Prospective Study

Alison Clifford1, Elana Murphy1, Steven Burrell2, Matthew Bligh3, Godfrey Heathcote3, Mathieu Castonguay3, Kara Thompson4 and John G. Hanly5, 1Rheumatology, Dalhousie University and Capital Health, Halifax, NS, Canada, 2Diagnostic imaging, Dalhousie University and Capital Health, Halifax, NS, Canada, 3Dalhousie University and Capital Health, Halifax, NS, Canada, 4Department of Medicine, Queen Elizabeth II Health Sciences Centre and Dalhousie University, Halifax, NS, Canada, 5Division of Rheumatology, Dalhousie University and Capital Health, Halifax, NS, Canada

Meeting: 2014 ACR/ARHP Annual Meeting

Keywords: biopsies and giant cell arteritis, Imaging

  • Tweet
  • Click to email a link to a friend (Opens in new window) Email
  • Click to print (Opens in new window) Print
Session Information

Title: Vasculitis

Session Type: Abstract Submissions (ACR)

Background/Purpose: Temporal artery (TA) biopsies are negative in up to 50% of patients with giant cell arteritis (GCA). In such cases, increased uptake in large arteries on PET/CT may support the clinical diagnosis. The objective of this study was to compare vascular (18F)-FDG uptake in patients with clinically diagnosed GCA to controls, and to compare uptake in GCA TA biopsy positive (TA+) patients to those with negative TA biopsies (TA-). Secondary outcomes evaluated the correlation of vascular uptake on PET/CT with clinical and laboratory variables and medications, including use of corticosteroids.

Methods: Patients with a clinical diagnosis of GCA and meeting ACR 1990 classification criteria were prospectively enrolled. Controls were identified from an oncology database, matched for age and sex. All GCA cases were treated per standard of care with high dose corticosteroids and underwent both TA biopsy and PET/CT. Using a 4 point scale, vascular FDG uptake was scored in 8 vascular territories and overall (total) by two nuclear medicine specialists, blinded to the clinical diagnosis. TA biopsies were interpreted by 2 anatomical pathologists with differences resolved by consensus. Statistical analysis used non-parametric Wilcoxon exact tests, Spearman correlations and analysis of variance.

Results: Twenty-eight patients with GCA (61% female, mean age ± SD: 70 ± 8.9 yrs) and 28 controls (61% female, 64 ± 8.2 yrs) were enrolled. TA biopsy was positive in 64% of GCA patients. Mean total PET/CT uptake scores were significantly higher in those with GCA (10.34 ± 2.72) compared to controls (7.73 ± 2.56, p=0.001.) Six of 8 vascular territories evaluated showed significantly greater uptake in GCA patients. TA+ and TA- GCA patients had similar total PET/CT uptake (10.86 ± 2.63 vs. 9.4 ± 2.76, p=0.2) and in each specific vascular territory. The optimal cut-off for distinguishing GCA cases from controls by total PET/CT uptake score was 9. This resulted in area under the curve of 0.75, with a sensitivity of 71.4% and specificity of 64.3%.  The presence of systemic symptoms (p=0.015), lower hemoglobin levels (p=0.009) and higher platelet counts (p=0.008) were associated with higher PET/CT scores but ESR and CRP levels were not. The only association with corticosteroids was between higher daily dose adjusted for body weight with higher total PET/CT scores (p=0.033).

Conclusion: Large vessel disease was identified in the majority (71.4%) of GCA patients by PET/CT despite initiation of corticosteroids, with similar uptake noted in TA+ and TA- patients. The sensitivity of PET/CT was superior to that of TA biopsy for identification of patients with a clinical diagnosis of GCA. Systemic symptoms, in particular, were associated with greater total uptake scores.


Disclosure:

A. Clifford,
None;

E. Murphy,
None;

S. Burrell,
None;

M. Bligh,
None;

G. Heathcote,
None;

M. Castonguay,
None;

K. Thompson,
None;

J. G. Hanly,
None.

  • Tweet
  • Click to email a link to a friend (Opens in new window) Email
  • Click to print (Opens in new window) Print

« Back to 2014 ACR/ARHP Annual Meeting

ACR Meeting Abstracts - https://acrabstracts.org/abstract/petct-for-the-diagnosis-of-giant-cell-arteritis-a-prospective-study/

Advanced Search

Your Favorites

You can save and print a list of your favorite abstracts during your browser session by clicking the “Favorite” button at the bottom of any abstract. View your favorites »

All abstracts accepted to ACR Convergence are under media embargo once the ACR has notified presenters of their abstract’s acceptance. They may be presented at other meetings or published as manuscripts after this time but should not be discussed in non-scholarly venues or outlets. The following embargo policies are strictly enforced by the ACR.

Accepted abstracts are made available to the public online in advance of the meeting and are published in a special online supplement of our scientific journal, Arthritis & Rheumatology. Information contained in those abstracts may not be released until the abstracts appear online. In an exception to the media embargo, academic institutions, private organizations, and companies with products whose value may be influenced by information contained in an abstract may issue a press release to coincide with the availability of an ACR abstract on the ACR website. However, the ACR continues to require that information that goes beyond that contained in the abstract (e.g., discussion of the abstract done as part of editorial news coverage) is under media embargo until 10:00 AM ET on November 14, 2024. Journalists with access to embargoed information cannot release articles or editorial news coverage before this time. Editorial news coverage is considered original articles/videos developed by employed journalists to report facts, commentary, and subject matter expert quotes in a narrative form using a variety of sources (e.g., research, announcements, press releases, events, etc.).

Violation of this policy may result in the abstract being withdrawn from the meeting and other measures deemed appropriate. Authors are responsible for notifying colleagues, institutions, communications firms, and all other stakeholders related to the development or promotion of the abstract about this policy. If you have questions about the ACR abstract embargo policy, please contact ACR abstracts staff at [email protected].

Wiley

  • Online Journal
  • Privacy Policy
  • Permissions Policies
  • Cookie Preferences

© Copyright 2025 American College of Rheumatology