Validation of the 2022 ACR/EULAR classification criteria for giant cell arteritis in Koran patients with giant cell arteritis.

Abstract

Objectives: We applied the 2022 American College of Rheumatology (ACR)/European Alliance of Association for Rheumatology (EULAR) criteria to Korean patients previously diagnosed with giant cell arteritis (GCA) according to the 1990 ACR criteria and validated its clinical efficiency.

Methods: Nine patients with GCA were included in this study. The proportion of patients meeting each item of the 1990 ACR criteria and the 2022 ACR/EULAR criteria were assessed. fluorodeoxyglucose-positron emission tomography (FDG-PET), and temporal artery biopsy were performed in eight, and four of the nine patients, respectively.

Results: The median age was 65.0 years, and 77.8% of the patients were women. Seven (77.8%) patients had polymyalgia rheumatica. All nine patients were reclassified as having GCA according to the 2022 ACR/EULAR criteria. Among the 10 items of the 2022 ACR/EULAR criteria, the item contributing the most to the reclassification was elevated acute-phase reactant levels (100%), followed by new temporal headache (77.8%), and FDG-PET activity throughout the aorta (77.5%). Positive temporal artery biopsy findings were observed in 75.0% of the patients; however, only four patients underwent biopsy, which was insufficient to assess its efficacy. An item of sudden visual loss did not make a considerable contribution to the reclassification of GCA because of its rare frequency (11.1%).

Conclusion: In this study, for the first time, we demonstrated a concordance rate of 100% between the two criteria in Korean patients previously diagnosed with GCA. Moreover, we also clarified the major contributors to the reclassification according to the 2022 ACR/EULAR criteria.