From the Guidelines
The workup for giant cell arteritis (GCA) should begin with a thorough history and physical examination, focusing on symptoms like new-onset headache, scalp tenderness, jaw claudication, visual disturbances, and constitutional symptoms, and should include laboratory tests, imaging, and temporal artery biopsy, with high-dose corticosteroids initiated immediately if GCA is strongly suspected, especially if vision is threatened, as recommended by the 2020 EULAR guidelines 1.
Key Components of the Workup
- A thorough history and physical examination to identify symptoms suggestive of GCA
- Laboratory tests, including erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), which are typically elevated in GCA
- Temporal artery biopsy, which remains the gold standard for diagnosis, ideally performed within 1-2 weeks of starting treatment, with a biopsy length of at least 1-2 cm to account for skip lesions
- Imaging studies, such as color duplex ultrasonography, MRI, CT, or PET scans, to help identify large-vessel involvement
Initiation of Treatment
- High-dose corticosteroids (prednisone 40-60 mg daily or equivalent) should be initiated immediately if GCA is strongly suspected, especially if vision is threatened, as recommended by the 2020 EULAR guidelines 1
- Treatment should not be delayed while awaiting biopsy results, as prompt initiation of corticosteroids can help prevent irreversible blindness
Tapering of Corticosteroids
- After diagnosis, steroids are typically continued for 2-4 weeks before slow tapering over months to years, guided by symptom control and inflammatory markers, as recommended by the 2020 EULAR guidelines 1
Recent Guidelines and Recommendations
- The 2020 EULAR guidelines recommend a thorough clinical and imaging assessment of the arterial tree when a diagnosis of GCA is suspected, and suggest that high-dose glucocorticoid therapy should be initiated immediately for induction of remission in active GCA 1
- The 2021 American College of Rheumatology/Vasculitis Foundation guideline for the management of GCA and Takayasu arteritis also recommends prompt initiation of high-dose corticosteroids for suspected GCA, especially if vision is threatened 1
From the Research
Diagnosis of Giant Cell Arteritis (GCA)
The workup for giant cell arteritis (GCA) involves a combination of clinical evaluation, laboratory tests, and temporal artery biopsy.
- Clinical symptoms such as new-onset headache, jaw claudication, proximal myalgia, weight loss, and fever may lead to the diagnosis 2.
- Laboratory values, including erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), can indicate GCA, but none of these values prove the diagnosis 2.
- Temporal artery biopsy is the gold standard for diagnosis of GCA, but a negative result does not exclude the diagnosis due to skip lesions 3, 2.
Temporal Artery Biopsy
- The biopsy should be performed as soon as possible after the initiation of corticosteroids, ideally within 2 weeks 4.
- The timing of the biopsy can affect its sensitivity, with a trend toward shorter duration of corticosteroid treatment in biopsy-positive patients 4.
- A duration of corticosteroid treatment of more than 7 days may be associated with lower rates of positive temporal artery biopsy 4.
Treatment and Monitoring
- High-dose steroids should be started as soon as the diagnosis is considered, and only withdrawn once it has been excluded 5.
- A gradual tapering of the steroid dose should occur over at least 1 year, with consideration of steroid-sparing agents if necessary 5.
- Careful monitoring of the response, both clinically and with serial inflammatory markers, is required 5.