Objective:

To compare the diagnostic yield of temporal artery ultrasound (TAUS) and temporal artery biopsy (TAB) in confirming giant cell arteritis in a single institution.

Background:

Giant cell arteritis (GCA) affects approximately 1 in 5000 U.S. adults. Diagnosis is typically based on clinical symptoms and elevation of erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP). Definitive diagnosis relies on TAB showing granulomatous inflammation and internal elastic lamina fragmentation. Recent studies suggest TAUS as a viable alternative to TAB.

Design/Methods:

This quality improvement initiative reviewed patients who underwent both TAB and TAUS between January 2019 and September 2025 at Trinity Health Grand Rapids, MI. Included were patients presenting with clinical features suggestive of GCA, elevated ESR and/or CRP. Diagnostic criteria were calculated for both TAB and TAUS. The area under the curve (AUC) was statistically compared between the procedures.

Results:

A total of 25 patients underwent both TAB and TAUS. Of those, 14 (56%) were diagnosed with GCA. TAB had a sensitivity of 85.7% (95% CI: 57.2%, 98.2%) and specificity of 100% (95% CI: 71.5%, 100%); while TAUS had a sensitivity of 21.4% (95% CI: 4.7%, 50.8%) and specificity of 72.7% (95% CI: 39.0%, 94%). The diagnostic accuracy of TAB was 92% vs 44% for TAUS. The AUC was significantly different (p<0.001) between TAB (AUC: 0.471; 95% CI: 0.293, 0.648) and TAUS (AUC: 0.929; 95% CI: 0.833, 1.000)

Conclusions:

The diagnostic utility of TAUS for GCA was poor compared to TAB in this single institution. While TAUS is a fast and non-invasive test to assist in the diagnosis of GCA, it is highly operator-dependent, and the sensitivity can be decreased by corticosteroid use. TAB remains the gold standard for diagnosis of GCA at our institution