Comparison of F18-FDG PET/CT findings with current clinical disease status in patients with Takayasu's arteritis.
OBJECTIVE
18F-fluorodeoxyglucose-positron emission tomography/computed tomography (F-18 FDG PET/CT) scanning has been proposed as a new tool to assess disease activity in Takayasu Arteritis (TA). We investigated whether F-18 FDG PET/CT findings were consistent with current clinical disease status in patients with TA.


METHODS
In this cross-sectional study, 22 patients with TA were enrolled. Clinical disease activity was assessed by the combination of National Institutes of Health (NIH) criteria, Disease Extent Index-Takayasu (DEI-Tak) score, physician global assessment and F-18 FDG PET/CT scans.


RESULTS
At the time F-18 FDG PET/CT scans were taken, the majority of the patients (17/22) were using immunosuppressive (IS) drugs, and only four patients had clinically active disease. F-18 FDG PET/CT scans confirmed the presence of active vasculitic lesions in those four patients. In 16 out of 18 patients who were accepted to be in clinical remission, F-18 FDG PET/CT scans were also normal. There were only two patients with discordant results, i.e. active F-18 FDG PET/CT findings despite the lack of clinical activity. Interestingly, clinical exacerbation occurred four weeks later in one of them. Overall sensitivity and specificity of F-18 FDG PET/CT findings for clinical activity were 100% and 88.9%, respectively.


CONCLUSIONS
We found that F-18 FDG PET/CT findings were generally consistent with clinical disease status in TA. Although use of IS drugs certainly impairs diagnostic accuracy of F-18 FDG PET/CT in TA, this imaging method may still have a potential for confirming remission or detecting disease activity in patients with TA receiving treatment.
Sifa University Medical Faculty, Department of Nuclear Medicine, Bornova/Izmir, Turkey. inanckarapolat@hotmail.com
I
I
Karapolat
M
M
Kalfa
G
G
Keser
M
M
Yalçin
V
V
Inal
K
K
Kumanlioğlu
T
T
Pirildar
K
K
Aksu
D000293:Adolescent; D000328:Adult; D016009:Chi-Square Distribution; D003430:Cross-Sectional Studies; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D049268:Positron-Emission Tomography; D011237:Predictive Value of Tests; D019275:Radiopharmaceuticals; D012008:Recurrence; D012074:Remission Induction; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D013625:Takayasu Arteritis / Q000000981:diagnostic imaging* / Q000188:drug therapy; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D055815:Young Adult
D007166:Immunosuppressive Agents; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18