How should I diagnose and treat a patient over 50 years old presenting with new persistent headache, scalp tenderness, jaw claudication, visual symptoms and markedly elevated erythrocyte sedimentation rate suggestive of giant cell arteritis?

Diagnosis and Treatment of Giant Cell Arteritis in Patients Over 50

Immediate Management – Do Not Delay Treatment

Start high-dose oral prednisone 40–60 mg daily immediately when clinical suspicion is high, without waiting for temporal artery biopsy or imaging results, because untreated GCA carries a 14–50% risk of permanent, irreversible vision loss. 1

For Patients WITH Visual Symptoms or Threatened Vision Loss

• Administer intravenous methylprednisolone 500–1000 mg daily for 3 consecutive days, then transition to high-dose oral prednisone 40–60 mg daily 1, 2
• This aggressive approach is critical because visual loss can occur within hours to days 1

For Patients WITHOUT Visual Symptoms

• Start oral prednisone 40–60 mg daily immediately 1
• Avoid routine IV pulse glucocorticoids in this group due to increased infection risk in elderly patients 1

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Clinical Diagnosis – High-Yield Features

Most Specific Symptoms (Positive Likelihood Ratios)

• Jaw claudication (pain with chewing that resolves with rest): LR+ 4.90, present in ~50% of patients 1, 2
• Temporal artery thickening on palpation: LR+ 4.70 1, 2
• Loss of temporal artery pulse: LR+ 3.25 1, 2
• Scalp tenderness: LR+ 3.14 1, 2
• Limb claudication: LR+ 6.01 (predicts severe ischemic complications) 1, 2

Common Presenting Features

• New-onset headache: present in 66–90% of biopsy-confirmed cases 1
• Visual disturbances (transient vision loss, diplopia, blurred vision): occur in 20% before permanent blindness 1, 2
• Constitutional symptoms: fever, weight loss ≥2 kg, fatigue, night sweats 1, 3
• Polymyalgia rheumatica symptoms: neck, shoulder, and pelvic girdle pain/stiffness 3

Physical Examination Essentials

• Palpate temporal arteries for thickening, tenderness, or absent pulse 1
• Assess scalp tenderness with light pressure 1
• Measure blood pressure in all four extremities to detect large-vessel disease 1
• Auscultate for bruits over axillary regions 1
• Perform comprehensive ophthalmologic evaluation if visual symptoms present 1

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Laboratory Evaluation

Inflammatory Markers (Present in >95% of Cases)

Marker	Threshold	Diagnostic Value
ESR	>100 mm/h	LR+ 3.11 [1]
ESR	<40 mm/h	LR– 0.18 (strongly excludes GCA) [1]
CRP	<2.5 mg/dL	LR– 0.38 (strongly excludes GCA) [1]
Platelet count	>400 × 10³/µL	LR+ 3.75 [1]

Critical caveat: Although rare (<5% of cases), GCA can present with normal ESR and CRP; high clinical suspicion should still prompt biopsy or imaging 1, 4. A delayed diagnosis based solely on normal inflammatory markers can cause substantial morbidity 4.

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Diagnostic Confirmation

Temporal Artery Biopsy (Gold Standard)

• Obtain a specimen ≥1 cm in length to minimize false-negatives from skip lesions (present in ~10% of cases) 1, 5
• Perform biopsy within 2 weeks of starting glucocorticoids; histopathologic changes remain detectable for 1–2 weeks after treatment initiation 1
• Biopsy should be performed by an experienced surgeon and evaluated by an experienced pathologist 1
• Do not delay glucocorticoid therapy while awaiting biopsy 1, 5
• If initial unilateral biopsy is negative but clinical suspicion remains high, proceed to contralateral biopsy 1

Histopathologic Findings

• Arterial wall thickening with luminal narrowing 1
• Mononuclear inflammatory infiltrates invading the media 1
• Multinucleated giant cells (may be absent in some cases) 1, 5

Vascular Imaging (When Biopsy Negative or Unavailable)

• Temporal artery ultrasound: "halo sign" (circumferential wall thickening) has 88% sensitivity and 97% specificity 1
• MR/CT angiography of neck, chest, abdomen, and pelvis: obtain at baseline to assess large-vessel involvement and provide reference for future monitoring 1, 6
• FDG-PET: shows increased tracer uptake in arterial walls 1
• Imaging performed within 24 hours of symptom onset lowers the incidence of permanent visual impairment 1

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Adjunctive Therapies

Tocilizumab (IL-6 Receptor Antagonist)

• Add tocilizumab at the time of diagnosis for all GCA patients to reduce cumulative glucocorticoid exposure and prevent disease relapses 1, 2, 6
• Tocilizumab is FDA-approved for GCA and is the preferred adjunctive agent 1
• Initiate at diagnosis rather than reserving for relapse management 1

Low-Dose Aspirin

• Prescribe aspirin 75–150 mg daily to all GCA patients to reduce cardiovascular and cerebrovascular ischemic events 1, 2, 6, 5

Alternative Steroid-Sparing Agents

• Methotrexate: use when tocilizumab is unavailable or contraindicated 1, 6, 3
• Abatacept: reasonable as adjunctive therapy 1

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Glucocorticoid Tapering Strategy

Do not use fixed tapering schedules; guide tapering by clinical symptoms and inflammatory markers (ESR/CRP). 1

Tapering Timeline

• Month 1: Maintain initial high dose (40–60 mg daily) 1
• Months 2–3: Taper to 15–20 mg daily 1, 2
• Month 12: Target ≤5 mg daily if disease is controlled 1, 2
• Therapy typically required for 1–2 years to avoid recurrence 1

Pitfalls to Avoid

• Do not use alternate-day dosing; daily dosing achieves higher remission rates 2
• Do not start with moderate doses (~30 mg daily); evidence for lower initial doses is low quality and vision loss risk is high 2

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Monitoring and Follow-Up

At Each Visit

• Assess headache, jaw claudication, visual changes, and constitutional symptoms 1
• Measure ESR and CRP to inform treatment adjustments 1, 3
• Monitor for glucocorticoid-related adverse effects (infection, osteoporosis, hyperglycemia) 1

Bone Protection

• Initiate calcium, vitamin D, and bisphosphonates for all patients unless contraindicated 1

Imaging Surveillance

• Perform periodic vascular imaging in patients with known large-vessel involvement to surveil for aneurysms, stenoses, and disease progression 1
• Vascular damage (particularly aortic aneurysm progression) may continue even during clinical remission 1

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Management of Disease Relapse

Up to 60% of patients experience relapses during glucocorticoid tapering 6

Relapse Protocol

• Escalate glucocorticoid dose 1
• Add or change non-glucocorticoid immunosuppressive agent (e.g., switch from methotrexate to tocilizumab, or add abatacept) 1

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Critical Pitfalls to Avoid

1. Never delay glucocorticoid initiation while awaiting biopsy or imaging; irreversible vision loss can occur within hours 1, 2, 5
2. Never use biopsy specimens <1 cm; skip lesions cause false-negatives 1, 2
3. Never rely solely on ACR 1990 classification criteria for clinical diagnosis; they are intended for research, not bedside decision-making 1
4. Never dismiss GCA based on normal ESR alone; rare cases (<5%) present with normal inflammatory markers 1, 4
5. Never assume negative temporal artery biopsy rules out GCA in stroke patients; isolated large-vessel GCA may lack temporal artery involvement—obtain large-vessel imaging 6