Ultrasound is useful for disease monitoring in giant cell arteritis

Disease activity in giant cell arteritis (GCA) patients can be well monitored by ultrasound. The number of temporal arterial segments with halo sign, and temporal arterial intimal-media thickness were sensitive to change over 24 weeks. Moreover, halo features and disease activity markers demonstrated significant associations. These results were not found for axillary arterial halo features [1].

In patients aged ≥50 years, GCA is the most prevalent form of primary vasculitis. Irreversible blindness occurs in up to 30% of the cases. Although high dose glucocorticoids are an effective treatment, toxicity is a major problem and occurs in over 80% of patients. Therefore, a correct diagnosis and accurate monitoring of the disease are important. In prior studies, a non-compressible halo sign of the temporal and axillary arteries has demonstrated discriminative value for diagnosing GCA [2].

The current 2-centre, prospective study aimed to assess the potential of ultrasound for monitoring newly diagnosed GCA patients by analysing the sensitivity to change of ultrasound halo characteristics, and their connection to disease activity and glucocorticoid therapy. To this end, ultrasound features of patients with clinical relapse were assessed. A total of 49 patients with ultrasound-confirmed GCA (mean age 78.2, 73.5% women) were included in the study. The sensitivity of halo to change was calculated by the mean difference of halo features (non-standardised variation) between baseline and the different timepoints (1, 3, 6, 12, and 24 weeks). Dr Cristina Ponte (Hospital de Santa Maria Lisbon, Portugal) shared the results of the study.

The sum of all arterial segments with halo –temporal and axillary arteries combined– demonstrated halo sensitivity to change over 24 weeks at all timepoints compared with baseline. The sum of halo intima-media thickness (IMT) demonstrated sensitivity to change at these timepoints as well. When temporal and axillary arteries were evaluated separately, only the sum of temporal arterial segments with halo and accessory IMT were sensitive to change at all timepoints (see Figure).

Figure: Halo sensitivity to change during disease follow-up [1]



IMT, intima-media thickness.

A significant association was found between the sum of all segments with halo and disease activity as measured by erythrocyte sedimentation rates, C-reactive protein, and Birmingham Vasculitis Activity Score (all P<0.05). Corresponding correlations for the sum of axillary halo segments and ESR, CRP, and BVAS were not significant. Correlations were similar for the sum of IMT of the separate arteries. In addition, a significant correlation was found between glucocorticoid cumulative dose and the sum of temporal segments with halo (-0.34; P<0.05). The sum of all segments with halo was related to the probability of being in disease remission, defined as an absence of relapse plus prednisone dose <30 mg/day (OR 0.47). Halo sign features of temporal segments were also associated with the probability of being in disease remission (OR 0.39). Finally, the sum of all segments with halo (P=0.0012) and temporal segments with halo (P=0.0012) were predictive of relapse. Dr Ponte concluded that ultrasound is a valuable tool in the monitoring of GCA patients: “A composite score of halo size and extent could be used to assess disease activity and treatment response in GCA patients.”

1. Ponte C, et al. Ultrasound halo sign as a potential monitoring tool for patients with giant cell arteritis: a prospective analysis. OP0055, EULAR 2021 Virtual Congress, 2–5 June.
2. Dejaco C, et al. Ann Rheum Dis 2018;77(5):636-43.

 

Copyright ©2021 Medicom Medical Publishers



Posted on 2 August 20213 August 2021