Treatment of Temporal Arteritis (Giant Cell Arteritis)
The treatment of temporal arteritis (giant cell arteritis) requires immediate initiation of high-dose glucocorticoids, with consideration for adding tocilizumab as a glucocorticoid-sparing agent to improve outcomes and reduce relapse rates. 1
Diagnostic Approach
- Temporal artery biopsy remains the gold standard for diagnosis of GCA, but treatment should not be delayed while awaiting biopsy results 2
- A unilateral temporal artery biopsy with a long segment (>1 cm) should be obtained within 2 weeks of starting glucocorticoids 2
- Noninvasive vascular imaging should be considered to evaluate large vessel involvement, especially in cases with negative biopsy results 2
Initial Treatment Based on Clinical Presentation
For Patients WITH Threatened Vision Loss:
- Immediately administer IV pulse glucocorticoids (methylprednisolone 500-1000 mg/day for 3-5 days) 2, 3
- Do not delay oral glucocorticoid treatment while arranging for IV therapy; start oral prednisone immediately if IV administration will be delayed 3
- Visual deterioration can occur within the first 5 days of treatment despite high-dose therapy 4
For Patients WITHOUT Threatened Vision Loss:
- Initiate high-dose oral glucocorticoids (prednisone 1 mg/kg/day, maximum 60-80 mg/day) 2, 1
- Daily dosing is preferred over alternate-day schedules 2, 1
- Maintain initial high-dose for approximately one month before beginning taper 2
Adjunctive Therapy
- Consider adding tocilizumab to glucocorticoid therapy, as it significantly reduces glucocorticoid requirements and flare rates 2, 1
- For patients with critical or flow-limiting involvement of vertebral or carotid arteries, add aspirin 2, 1
- Methotrexate may be considered as a glucocorticoid-sparing agent in patients who experience serious side effects from glucocorticoids 5
Glucocorticoid Tapering
- Maintain initial high-dose glucocorticoids for approximately one month 2
- Taper gradually based on clinical symptoms and normalization of inflammatory markers (ESR and CRP) 2, 1
- At 3 months, the glucocorticoid dose is typically between 10-15 mg/day 2
- The total duration of glucocorticoid therapy is variable and may extend to several years 2, 6
Management of Relapse
- For patients experiencing disease relapse while on moderate-to-high dose glucocorticoids, add a non-glucocorticoid immunosuppressive agent 2
- For relapse with symptoms of cranial ischemia, add a non-glucocorticoid immunosuppressive agent and increase glucocorticoid dose 2
- Tocilizumab is preferred over methotrexate for relapse with symptoms of cranial ischemia 2, 1
Monitoring
- Regular clinical monitoring is essential for all patients with GCA 2
- Monitor for clinical symptoms, normalization of inflammatory markers (ESR and CRP), and potential glucocorticoid-related adverse effects 2, 1
- Up to 60% of patients will experience one or more relapses during glucocorticoid tapering 1
Important Considerations
- GCA is a medical emergency due to the risk of permanent vision loss, which occurs in 15-35% of patients primarily before initiation of therapy 3, 1
- If one eye is affected, the risk for losing vision in the second eye is as high as 50% without treatment 3, 1
- Glucocorticoids may prevent but usually do not reverse visual loss that has already occurred 5, 7
- All patients on long-term glucocorticoids should receive bone protection therapy 1
Treatment Duration
- The total duration of treatment is highly variable, with many patients requiring therapy for 1-2 years 5
- Some patients may have a more chronic-relapsing course requiring low-dose glucocorticoids for several years 5, 6
- Treatment should continue until there is no clinical evidence of active disease and inflammatory markers remain stable 2