Follow-up ultrasound examination in patients with newly diagnosed giant cell arteritis.

Objectives: Ultrasound is a standard tool to diagnose giant cell arteritis (GCA). Until now, only few studies investigated the role of ultrasound in the follow-up of GCA. The aim of this study was to assess the changes in the intima media thickness (IMT), total number of affected arteries and provisional OMERACT GCA ultrasonography score (OGUS) in a 12-months follow-up period.

Methods: Patients with newly diagnosed GCA were prospectively enrolled. Ultrasound examinations of facial, temporal, carotid, vertebral and axillary arteries were performed at baseline, after three, six, nine and 12 months. Changes of IMT, total number of affected arteries, and OGUS values were evaluated. In a subgroup of patients, exams were conducted weekly in the first 100 days.

Results: Fifty patients were enrolled, 36 completed the follow-up. Significant reductions in IMT, total number of affected arteries and OGUS were observed. Eighteen patients presented to weekly exams. The mean IMT of the axillary artery normalized after seven days, while IMT of the common temporal artery normalized after 50 days. The mean OGUS values were below one after six months. There were no differences in IMT changes between GCA patients with or without PMR or between those with and without additional tocilizumab treatment. A relapse occurred in 4 patients. At relapse, mean IMT and OGUS were higher as compared with the preceding assessment. No predictive values indicating a relapse were identified.

Conclusion: Vascular ultrasound is sensitive to change in GCA. The presence of PMR or treatment with tocilizumab did not affect IMT decrease.