Objective: It is urgent to diagnose giant cell arteritis (GCA) as quickly as possible to prevent irreversible blindness. The traditional gold standard for diagnosing GCA is temporal artery biopsy (TAB). However, TAB lacks diagnostic performance and carries out risks of surgical intervention. The noninvasive color Doppler ultrasound (CDU) seems to be a promising alternative. This study is designed to assess the diagnostic value of CDU in daily clinical practice.
Methods: In this prospective cohort study, patients with a clinical suspicion of active GCA were included and underwent a CDU of the temporal arteries. If deemed necessary by the referrer, a TAB and/or 18F-fluorodeoxyglucose positron emission tomography with computed tomography was performed. The retrospective clinical diagnosis was determined 1 year after inclusion by two physicians experienced in the field of vasculitis.
Results: 242 patients were included and GCA was diagnosed in 73 (30%) patients by the defined retrospective clinical diagnosis. Compared with the retrospective diagnosis, CDU has a sensitivity of 60% (48-72), specificity of 94% (89-97), positive predictive value (PPV) of 81% (70-89), negative predictive value (NPV) of 85% (80-88), and an accuracy of 84% (78-88). A total of 84 (35%) patients underwent TAB. TAB has a sensitivity of 66% (51-79), specificity of 100% (90-100), PPV of 100% (100), NPV of 67% (58-75), and an accuracy of 80% (70-88).
Conclusion: This study shows comparable diagnostic performance for CDU and TAB and even better CDU results with a bilateral halo present. Considering the advantages of the noninvasive CDU, it is the diagnostic tool of choice.
© 2023 The Authors. ACR Open Rheumatology published by Wiley Periodicals LLC on behalf of American College of Rheumatology.