To assess the value of contrast-enhanced ultrasonography (CEUS) for monitoring disease activity of Takayasu arteritis (TA).
TA patients were recruited in a Chinese TA clinical center from January 2016 to September 2017. The physician global assessment was used as the referential standard for disease activity. Clinical data, acute phase reactants, and CEUS scans were simultaneously recorded at baseline and after a 3-month therapy.
A total of 84 TA patients were enrolled, and 47 (55.95%) cases were active at baseline. Macaroni sign and entire artery involvement were characteristic findings of CEUS in TA. The average vascular full thickness of the carotid artery in active TA patients was significantly higher than that in inactive patients (2.36 ± 0.86 vs. 1.79 ± 0.49 mm; p = 0.001). Severe neovascularization (grade 2) was observed in 29 active cases (61.70%) and in 9 inactive cases (24.32%) (p = 0.001). Receiver operating characteristic analysis showed that the combination of CEUS parameters (cutoff of thickness was 1.75 mm or neovascularization grade 2) and erythrocyte sedimentation rate (ESR) (cutoff of 20 mm/H) could help differentiate between active and inactive TA patients with a sensitivity and specificity of 81.1% and 81.5%, respectively. Youdon's index was 0.626. Furthermore, our study found that patients with decreased ESR and C-reactive protein (CRP) still had a progression of vascular wall inflammation at 3 months of follow-up.
The evaluation of vascular inflammation by CEUS is more sensitive than acute phase reactants. Neovascularization can still be observed in the vascular lesion sites of those who have reached clinical remission after treatment. Thus, CEUS can be used as an alternative method to assess disease activity for TA patients.