Ultrasound is a viable imaging tool for monitoring patients with giant cell arteritis (GCA), according to study results published in Annals of the Rheumatic Diseases. Study results also suggested a significant association between temporal artery halo characteristics and disease activity markers and cumulative glucocorticoid dose.
A team of researchers conducted a prospective observational cohort study of patients with newly diagnosed GCA to determine sensitivity to changes in ultrasound halo characteristics and their correlation with disease activity and glucocorticoid treatment.
In a total of 49 patients (73.5% women; mean age 78.2 years) with ultrasound-confirmed GCA, serial ultrasound examinations of the temporalis and axillary arteries were performed at specified times, with the number of segments with halo and maximum halo intima-media thickness being recorded . The researchers then compared the clinical picture and the first relapse.
A total of 354 visits were recorded during the study period, with a mean of 7.2 visits over a mean of 307.5 days. Prior to initiating ultrasound, patients received high-dose glucocorticoid treatment for an average of 2.5 days and received an average cumulative prednisolone (or equivalent) dose of 927.3 mg. At the start of the ultrasound scan, all patients had at least 1 arterial segment with a halo sign; 220 arterial segments with halo were recorded (201 and 19 temporal and axillary artery segments, respectively). Of the cohort, 47 (95.9%) patients had temporal artery involvement, 2 (22.4%) had axillary involvement, and 9 (18.4%) had both.
Halo sensitivity to change was measured at baseline and at weeks 1, 3, 6, 12, and 24. A total of 250 research visits were included. Of the 36 patients at week 24, 16 (44.4%) reported a halo sign; 12 patients had temporal artery involvement and 5 patients had axillary involvement. Disease relapse was observed in 3 (18.8%) patients; However, there was an increase in the number of halo and halo sized arterial segments in these patients compared to the previous recorded visits.
During the 24-week follow-up, a positive correlation was observed between temporal artery halo features and disease activity markers such as erythrocyte sedimentation rate, C-reactive protein, and Birmingham Vasculitis Activity Score; however, no significant correlation was found for axillary artery halo characteristics.
Patients with fewer temporal artery sections with halo and lower temporal intima-media thickness values were more likely to achieve disease remission. However, this association was not observed with axillary halo features.
Limitations of the study included the fact that the ultrasound machines were not blinded to clinical data and that many patients were referred to the study by the eye clinic, increasing the tendency for GCA to have a more cranial phenotype.
“Rather than the current binary presence / absence of halo signs in an arterial segment, the assessment of ultrasound-specific halo features should be used to assess disease activity and response to treatment in patients with GCA. Future clinical trials of GCA should examine the effect of treatment on halo traits as an outcome measure, ”the researchers noted.
Ponte C, Monti S, Scirè CA, et al. Ultrasonic halo signs as a potential monitoring tool for patients with giant cell arteritis: a prospective analysis. Ann Rheum Dis. Published online July 2, 2021. doi: 10.1136 / annrheumdis-2021-220306
This article originally appeared on Rheumatology Advisor