Temporal Artery Biopsy Does Not Lead to Shorter Steroid Duration in Patients With Suspected Giant Cell Arteritis

Giant cell arteritis (GCA) is a serious medical condition that can lead to blindness if not promptly diagnosed and treated. Multiple modalities have been proposed for accurate diagnosis of GCA, such as temporal artery ultrasound and 18F-FDG PET/CT, as compared to the gold standard histopathology of the temporal artery. Despite the high specificity of temporal artery biopsy (TAB) for diagnosing GCA, the sensitivity remains significantly lower. Although TAB is often performed, the results of the biopsy do not always influence the clinical management of GCA. The aim of this study was to determine what impact, if any, the results of TAB had on the duration of high dose steroid therapy for GCA. A single-center, retrospective study at our tertiary care institution was performed. Adult patients with suspected GCA who underwent TAB between January 1, 2019, and September 30, 2023, were included. Patients with incomplete records or mortality within 30 days were excluded. High-dose steroid use (defined as greater or equal to 40 mg of prednisone or equivalent glucocorticoid dose, daily), duration of therapy, and work-up prior to TAB consultation were collected in addition to the biopsy results. A total of 135 of 142 reviewed cases met inclusion criteria, with 86% (n = 116) of patients having a negative biopsy. Of those with a negative biopsy, high-dose glucocorticoids were continued in 49.1% (n = 57) of patients for greater than 4 weeks, 31.8% (n = 37) for greater than 6 weeks, and 20.7% (n = 24) beyond 8 weeks. There was no statistically significant difference between biopsy result and steroid duration (P < .001). Prior to biopsy, 54% (n = 73) of patients met clinical diagnosis of GCA by the American College of Rheumatology/EULAR classification criteria. Bilateral biopsies were performed in 35 patients (26%), and none of these had laterality discordance in diagnosis. Temporal artery ultrasound was obtained in 10 patients prior to biopsy, none of which showed any abnormalities, and only one of which had a positive biopsy result. At our tertiary care institution, only a small percentage of TABs performed provided positive confirmation of GCA. However, the duration of high-dose steroid therapy was not shortened despite a negative biopsy result. Given the lack of clinical impact of TAB at our institution, we suggest further research to validate the use of alternative, less invasive diagnostic tests and/or imaging modalities. There may be a role for a multidisciplinary consensus statement to provide evidence-based recommendations for diagnosis of GCA.