Ultrasonography-led multimodal diagnostic pathway for giant cell arteritis

Area of Science:

• Rheumatology
• Diagnostic Imaging
• Internal Medicine

Background:

• Giant cell arteritis (GCA) diagnosis relies on clinical suspicion and invasive tests.
• Current diagnostic methods have limitations in sensitivity and specificity.
• A multimodal approach may improve diagnostic accuracy for GCA.

Purpose of the Study:

• To evaluate the sensitivity and negative predictive value of a diagnostic pathway for GCA.
• To assess the utility of ultrasonography, 18-fluorodeoxyglucose labelled PET-CT, and temporal artery biopsy in GCA diagnosis.

Main Methods:

• 1000 consecutive GCA referrals were analyzed.
• A protocolized examination included ultrasonography, CRP levels, and extended ultrasound if indicated.
• A second test (temporal artery biopsy or PET-CT) was offered for negative initial assessments.

Main Results:

• Positive ultrasonography was found in 279/1000 patients.
• Extended ultrasonography and a second test increased diagnostic sensitivity to 95.7% and negative predictive value to 98.0% for GCA.
• Temporal artery biopsy yielded positive results in 24/139, and PET-CT in 7/42.

Conclusions:

• This study provides real-world evidence for the effectiveness of a multimodal diagnostic pathway for GCA.
• Ultrasonography, as part of a multimodal strategy, is valuable for diagnosing giant cell arteritis.
• The combined approach significantly enhances diagnostic performance compared to single-modality testing.