Giant Cell Arteritis (Temporal Arteritis)

Giant cell arteritis (GCA), also known as temporal arteritis, is an inflammatory condition affecting medium and large arteries, particularly the temporal arteries (near the temples) and the arteries supplying the eyes. GCA is a medical emergency because it can cause permanent blindness if not treated promptly.

Patient Awareness Guide

If you're over 50, knowing the warning signs of GCA could save your sight. For detailed information about recognizing symptoms and understanding the urgency of treatment, see our guide: Eye Symptoms After 50 - Giant Cell Arteritis Awareness Guide.

Warning Signs

Symptoms

Eye Symptoms (Ophthalmic)

• Transient vision loss—warning sign; brief episodes of vision blacking out
• Permanent vision loss—ischemic optic neuropathy or central retinal artery occlusion
• Double vision—from ischemia to eye muscles
• Vision loss is typically sudden and painless
• Without treatment, other eye often affected within days

Headache and Scalp Symptoms

• New headache or change in usual headache pattern
• Often located at temples
• Scalp tenderness—hurts to touch, comb hair, wear hat
• Visible or tender temporal arteries
• Arteries may feel thickened or have reduced pulse

Jaw Claudication

• Pain or fatigue in jaw muscles when chewing
• Caused by inadequate blood flow to jaw muscles
• Very specific for GCA when present
• More common with prolonged chewing

Systemic Symptoms

• Fatigue, malaise, feeling unwell
• Low-grade fever
• Weight loss
• Night sweats
• Shoulder and hip stiffness (polymyalgia rheumatica in 40-60%)

Who Gets GCA?

• Almost never occurs under age 50
• Average age at diagnosis: 70-75 years
• Women affected 2-3 times more than men
• More common in Northern Europeans
• Incidence increases with age

Diagnosis

Blood Tests (Urgent)

• ESR (erythrocyte sedimentation rate)—usually markedly elevated (often >50-100)
• CRP (C-reactive protein)—usually elevated
• CBC—may show anemia, elevated platelets

Important: Normal ESR/CRP doesn't completely rule out GCA in suspicious cases

Temporal Artery Biopsy

• Gold standard for diagnosis
• Removes small segment of temporal artery
• Shows inflammation of artery wall if positive
• Can be done under local anesthesia
• Should be done within 2 weeks of starting steroids
• Do NOT delay treatment waiting for biopsy

Imaging

• Temporal artery ultrasound—"halo sign" suggests inflammation
• MRI or PET scan—may show large vessel involvement
• May help if biopsy is negative but suspicion remains high

Treatment

Emergency Steroid Treatment

Start immediately if GCA suspected—don't wait for biopsy results

For vision involvement or visual warning signs:

• IV methylprednisolone 1 gram daily for 3-5 days
• Then transition to oral prednisone (60-80mg daily)

For GCA without vision involvement:

• High-dose oral prednisone (40-60mg daily)
• Some physicians still use IV steroids initially

Long-Term Treatment

Steroid taper:

• Very slow reduction over 1-2 years typically
• Guided by symptoms and inflammatory markers
• Relapses common if tapered too quickly

Steroid-sparing agents:

• Tocilizumab (Actemra)—FDA-approved for GCA
  • Allows faster steroid tapering
  • Given as weekly injection or monthly infusion
  • Reduces steroid side effects

Bone protection:

• Calcium and vitamin D
• Bisphosphonate medication
• Important because of prolonged steroid use

Monitoring

• Regular blood tests (ESR, CRP, blood sugar, etc.)
• Monitor for steroid side effects
• Watch for relapse symptoms
• Taper slowly based on clinical response

Complications

Visual Complications

• Permanent vision loss—most feared complication
• Ischemic optic neuropathy—most common
• Central retinal artery occlusion—sudden complete vision loss
• Ischemic cranial nerve palsies—double vision

Other Complications

• Aortic aneurysm—late complication, monitor with imaging
• Stroke—from involvement of intracranial arteries
• Limb claudication—from large vessel involvement
• Treatment complications—diabetes, osteoporosis, infections from steroids

Prognosis

With Prompt Treatment

• Excellent chance of preventing further vision loss
• Other eye protected with treatment
• Symptoms typically improve within days
• Most people can eventually taper off medication

Without Treatment

• High risk of second eye blindness (often within days)
• Risk of stroke and other vascular complications
• Vision loss in affected eye rarely recovers

Living with GCA

During Active Treatment

• Take medications exactly as prescribed
• Don't stop steroids suddenly
• Report any new symptoms immediately
• Attend all follow-up appointments
• Be aware of steroid side effects

Long-Term

• Regular monitoring even after treatment stops
• Watch for signs of relapse
• Periodic imaging to check for aortic aneurysm
• Healthy lifestyle to offset steroid side effects

Frequently Asked Questions

Why must treatment start before the biopsy?

Because vision loss can occur suddenly and is usually permanent. The risk of waiting (potential blindness) far outweighs the risk of starting steroids. The biopsy can still be positive up to 2 weeks after starting treatment.

If my biopsy is negative, does that mean I don't have GCA?

Not necessarily. GCA can affect arteries in a patchy pattern, so the biopsy may miss involved areas (false negative). If clinical suspicion is high despite negative biopsy, treatment may continue. Other tests like ultrasound or PET scan may help.

How long will I need to take steroids?

Typically 1-2 years, with very gradual tapering. Trying to reduce too quickly often leads to relapse. Tocilizumab may allow faster steroid reduction in some patients.

What if I've already lost vision in one eye?

Treatment is still urgent to protect the other eye. Without treatment, there's a very high risk of the second eye being affected, often within days. Vision in the already-affected eye rarely improves.

Can GCA come back after I finish treatment?

Relapse can occur, especially if steroids are tapered too quickly. Long-term monitoring is important. Some people need to stay on low-dose steroids or other medications indefinitely.

References