RT Journal Article
SR Electronic
T1 Positron Emission Tomography/Computerized Tomography in Newly Diagnosed Patients with Giant Cell Arteritis Who Are Taking Glucocorticoids
JF The Journal of Rheumatology
JO J Rheumatol
FD The Journal of Rheumatology
SP 1859
OP 1866
DO 10.3899/jrheum.170138
VO 44
IS 12
A1 Alison H. Clifford
A1 Elana M. Murphy
A1 Steven C. Burrell
A1 Mathew P. Bligh
A1 Ryan F. MacDougall
A1 J. Godfrey Heathcote
A1 Mathieu C. Castonguay
A1 Min S. Lee
A1 Kara Matheson
A1 John G. Hanly
YR 2017
UL http://www.jrheum.org/content/44/12/1859.abstract
AB Objective. Large vessel uptake on positron emission tomography/computerized tomography (PET/CT) supports the diagnosis of giant cell arteritis (GCA). Its value, however, in patients without arteritis on temporal artery biopsy and in those receiving glucocorticoids remains unknown. We compared PET/CT results in GCA patients with positive (TAB+) and negative temporal artery biopsies (TAB−), and controls.Methods. Patients with new clinically diagnosed GCA starting treatment with glucocorticoids underwent temporal artery biopsy and PET/CT. Using a visual semiquantitative approach, 18F-fluorodeoxyglucose (FDG) uptake was scored in 8 vascular territories and summed overall to give a total score in patients and matched controls.Results. Twenty-eight patients with GCA and 28 controls were enrolled. Eighteen patients with GCA were TAB+. Mean PET/CT scores after an average of 11.9 days of prednisone were higher in patients with GCA compared to controls, for both total uptake (10.34 ± 2.72 vs 7.73 ± 2.56; p = 0.001), and in 6 of 8 specific vascular territories. PET/CT scores were similar between TAB+ and TAB− patients with GCA. The optimal cutoff for distinguishing GCA cases from controls was a total PET/CT score of ≥ 9, with an area under the receiver-operating characteristic curve of 0.75, sensitivity 71.4%, and specificity 64.3%. Among patients with GCA, these measures correlated with greater total PET/CT scores: systemic symptoms (p = 0.015), lower hemoglobin (p = 0.009), and higher platelet count (p = 0.008).Conclusion. Vascular FDG uptake scores were increased in most patients with GCA despite exposure to prednisone; however, the sensitivity and specificity of PET/CT in this setting were lower than those previously reported.