Overview
Also known as temporal arteritis, giant cell arteritis (GCA) is the inflammation of medium- and large-sized arteries of unknown aetiology which is strongly linked with polymyalgia rheumatica (PMR).
The most common and serious complication of GCA is the irreversible loss of vision secondary to optic nerve ischaemia, making it a medical emergency.
Epidemiology
- Rates are more often reported in Northern European countries
- Women are 2-3 times more affected than men
- GCA is generally seen in patients >50 years
Risk Factors & Associations
- Female sex
- Northern European ancestry
- Polymyalgia rheumatica history
Presentation
Symptoms arise subacutely (generally <1 month):
- Headache
- Scalp pain/tenderness
- Patients often notice this when brushing their hair
- Jaw pain and claudication
- Visual disturbances:
- Diplopia
- Painless loss of vision
- Changes to colour vision
- Due to anterior ischaemic optic neuropathy – fundoscopy shows a pale, swollen optic disc with blurred margins
- Abnormality in palpating the temporal arteries:
- They may be palpable
- They may be tender
- They may have an absent pulse
- They may be enlarged
- These may feel “beady”
- Non-specific systemic symptoms:
- Low-grade fever
- Muscle aches
- Anorexia
- Night sweats
- Lethargy
Investigations
- Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP):
- Ideally before starting high-dose corticosteroids
- Usually elevated and fall with corticosteroid use
- Vascular ultrasonography of the temporal artery:
- Wall thickening which may be non-compressible – halo sign
- Stenosis or occlusion
- Temporal artery biopsy:
- Do not perform a biopsy if this delays treatment
- Done if ultrasonography cannot be done or the clinical suspicion is high but ultrasonography is normal
- Shows skip lesions
Management
Suspected GCA
- Immediate high-dose oral corticosteroids:
- This is done before the temporal artery biopsy
- No visual loss: high-dose oral prednisolone
- Visual loss present: IV methylprednisolone is given first, followed by high-dose prednisolone
- Urgent ophthalmology review:
- If patients have visual loss, they should be seen on the same day
- Offer bone protection
- Patients taking long-term and tapering doses of corticosteroids should be given calcium, vitamin D, and bisphosphonates to prevent glucocorticoid-induced osteoporosis
There should be a significant improvement with corticosteroid use. If there is not, an alternate diagnosis should be considered
Monitoring
- During corticosteroid tapering, patients should be monitored for adverse effects and have their inflammatory markers measured to evaluate their response to treatment
- Patients taking long-term corticosteroids should be monitored for diabetes, elevated blood pressure, and glucocorticoid-induced osteoporosis.
Complications
- Irreversible vision loss
- Glucocorticoid-related adverse effects
- Aneurysms and stenosis of the aorta and its major branches
Prognosis
- Visual damage is often irreversible
- Although treatment is effective, spontaneous relapses are common and can be unpredictable
- Factors that indicate longer corticosteroid regimens are older age at diagnosis, female and higher baseline ESR
